{"id":4777,"date":"2020-02-13T13:03:07","date_gmt":"2020-02-13T05:03:07","guid":{"rendered":"https:\/\/www.xttblog.com\/?p=4777"},"modified":"2020-02-13T13:03:07","modified_gmt":"2020-02-13T05:03:07","slug":"75-%e9%81%93java%e9%ab%98%e7%ba%a7%e5%b7%a5%e7%a8%8b%e5%b8%88%e9%9d%a2%e8%af%95%e9%a2%98%e5%90%ab%e7%ad%94%e6%a1%88","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=4777","title":{"rendered":"75 \u9053Java\u9ad8\u7ea7\u5de5\u7a0b\u5e08\u9762\u8bd5\u9898(\u542b\u7b54\u6848)"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">2020 \u7684\u5f00\u5c40\u771f\u7684\u56f0\u96be\u554a\uff0c\u5f88\u591a\u5c0f\u7684\u4f01\u4e1a\u751f\u5b58\u7279\u522b\u56f0\u96be\uff0c\u4e3a\u6b64\u5927\u5bb6\u8981\u591a\u51c6\u5907\u70b9\u9762\u8bd5\u9898\u8fdb\u884c\u6fc0\u70c8\u7684\u7ade\u4e89\uff01<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4eca\u5e74\u7fa4\u91cc\u4e0d\u5c11\u7f51\u53cb\u9700\u8981\u5237\u9762\u8bd5\u9898\uff0c\u6211\u8fd9\u91cc\u51c6\u5907\u4e86 75 \u9053\u5e38\u7528\u9762\u8bd5\u9898\uff0c\u5206\u4eab\u7ed9\u5927\u5bb6\uff01<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">1\u3001\u5728 java \u4e2d\u5b88\u62a4\u7ebf\u7a0b\u548c\u672c\u5730\u7ebf\u7a0b\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">java \u4e2d\u7684\u7ebf\u7a0b\u5206\u4e3a\u4e24\u79cd\uff1a\u5b88\u62a4\u7ebf\u7a0b\uff08Daemon\uff09\u548c\u7528\u6237\u7ebf\u7a0b\uff08User\uff09\u3002\u4efb\u4f55\u7ebf\u7a0b\u90fd\u53ef\u4ee5\u8bbe\u7f6e\u4e3a\u5b88\u62a4\u7ebf\u7a0b\u548c\u7528\u6237\u7ebf\u7a0b\uff0c\u901a\u8fc7\u65b9\u6cd5 Thread.setDaemon(boolon)\uff1btrue \u5219\u628a\u8be5\u7ebf\u7a0b\u8bbe\u7f6e\u4e3a\u5b88\u62a4\u7ebf\u7a0b\uff0c\u53cd\u4e4b\u5219\u4e3a\u7528\u6237\u7ebf\u7a0b\u3002Thread.setDaemon()\u5fc5\u987b\u5728 Thread.start()\u4e4b\u524d\u8c03\u7528\uff0c\u5426\u5219\u8fd0\u884c\u65f6\u4f1a\u629b\u51fa\u5f02\u5e38\u3002\u4e24\u8005\u7684\u533a\u522b\uff1a\u552f\u4e00\u7684\u533a\u522b\u662f\u5224\u65ad\u865a\u62df\u673a(JVM)\u4f55\u65f6\u79bb\u5f00\uff0cDaemon \u662f\u4e3a\u5176\u4ed6\u7ebf\u7a0b\u63d0\u4f9b\u670d\u52a1\uff0c\u5982\u679c\u5168\u90e8\u7684 User Thread \u5df2\u7ecf\u64a4\u79bb\uff0cDaemon \u6ca1\u6709\u53ef\u670d\u52a1\u7684\u7ebf\u7a0b\uff0cJVM \u64a4\u79bb\u3002\u4e5f\u53ef\u4ee5\u7406\u89e3\u4e3a\u5b88\u62a4\u7ebf\u7a0b\u662f JVM \u81ea\u52a8\u521b\u5efa\u7684\u7ebf\u7a0b\uff08\u4f46\u4e0d\u4e00\u5b9a\uff09\uff0c\u7528\u6237\u7ebf\u7a0b\u662f\u7a0b\u5e8f\u521b\u5efa\u7684\u7ebf\u7a0b\uff1b\u6bd4\u5982 JVM 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class=\"wp-block-heading\">2\u3001\u7ebf\u7a0b\u4e0e\u8fdb\u7a0b\u7684\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fdb\u7a0b\u662f\u64cd\u4f5c\u7cfb\u7edf\u5206\u914d\u8d44\u6e90\u7684\u6700\u5c0f\u5355\u5143\uff0c\u7ebf\u7a0b\u662f\u64cd\u4f5c\u7cfb\u7edf\u8c03\u5ea6\u7684\u6700\u5c0f\u5355\u5143\u3002\u4e00\u4e2a\u7a0b\u5e8f\u81f3\u5c11\u6709\u4e00\u4e2a\u8fdb\u7a0b,\u4e00\u4e2a\u8fdb\u7a0b\u81f3\u5c11\u6709\u4e00\u4e2a\u7ebf\u7a0b\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3\u3001\u4ec0\u4e48\u662f\u591a\u7ebf\u7a0b\u4e2d\u7684\u4e0a\u4e0b\u6587\u5207\u6362\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u591a\u7ebf\u7a0b\u4f1a\u5171\u540c\u4f7f\u7528\u4e00\u7ec4\u8ba1\u7b97\u673a\u4e0a\u7684 CPU\uff0c\u800c\u7ebf\u7a0b\u6570\u5927\u4e8e\u7ed9\u7a0b\u5e8f\u5206\u914d\u7684 CPU \u6570\u91cf\u65f6\uff0c\u4e3a\u4e86\u8ba9\u5404\u4e2a\u7ebf\u7a0b\u90fd\u6709\u6267\u884c\u7684\u673a\u4f1a\uff0c\u5c31\u9700\u8981\u8f6e\u8f6c\u4f7f\u7528 CPU\u3002\u4e0d\u540c\u7684\u7ebf\u7a0b\u5207\u6362\u4f7f\u7528 CPU\u53d1\u751f\u7684\u5207\u6362\u6570\u636e\u7b49\u5c31\u662f\u4e0a\u4e0b\u6587\u5207\u6362\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">4\u3001\u6b7b\u9501\u4e0e\u6d3b\u9501\u7684\u533a\u522b\uff0c\u6b7b\u9501\u4e0e\u9965\u997f\u7684\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6b7b\u9501\uff1a\u662f\u6307\u4e24\u4e2a\u6216\u4e24\u4e2a\u4ee5\u4e0a\u7684\u8fdb\u7a0b\uff08\u6216\u7ebf\u7a0b\uff09\u5728\u6267\u884c\u8fc7\u7a0b\u4e2d\uff0c\u56e0\u4e89\u593a\u8d44\u6e90\u800c\u9020\u6210\u7684\u4e00\u79cd\u4e92\u76f8\u7b49\u5f85\u7684\u73b0\u8c61\uff0c\u82e5\u65e0\u5916\u529b\u4f5c\u7528\uff0c\u5b83\u4eec\u90fd\u5c06\u65e0\u6cd5\u63a8\u8fdb\u4e0b\u53bb\u3002\u4ea7\u751f\u6b7b\u9501\u7684\u5fc5\u8981\u6761\u4ef6\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u4e92\u65a5\u6761\u4ef6\uff1a\u6240\u8c13\u4e92\u65a5\u5c31\u662f\u8fdb\u7a0b\u5728\u67d0\u4e00\u65f6\u95f4\u5185\u72ec\u5360\u8d44\u6e90\u3002<\/li><li>\u8bf7\u6c42\u4e0e\u4fdd\u6301\u6761\u4ef6\uff1a\u4e00\u4e2a\u8fdb\u7a0b\u56e0\u8bf7\u6c42\u8d44\u6e90\u800c\u963b\u585e\u65f6\uff0c\u5bf9\u5df2\u83b7\u5f97\u7684\u8d44\u6e90\u4fdd\u6301\u4e0d\u653e\u3002<\/li><li>\u4e0d\u5265\u593a\u6761\u4ef6:\u8fdb\u7a0b\u5df2\u83b7\u5f97\u8d44\u6e90\uff0c\u5728\u672b\u4f7f\u7528\u5b8c\u4e4b\u524d\uff0c\u4e0d\u80fd\u5f3a\u884c\u5265\u593a\u3002<\/li><li>\u5faa\u73af\u7b49\u5f85\u6761\u4ef6:\u82e5\u5e72\u8fdb\u7a0b\u4e4b\u95f4\u5f62\u6210\u4e00\u79cd\u5934\u5c3e\u76f8\u63a5\u7684\u5faa\u73af\u7b49\u5f85\u8d44\u6e90\u5173\u7cfb\u3002<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">\u6d3b\u9501\uff1a\u4efb\u52a1\u6216\u8005\u6267\u884c\u8005\u6ca1\u6709\u88ab\u963b\u585e\uff0c\u7531\u4e8e\u67d0\u4e9b\u6761\u4ef6\u6ca1\u6709\u6ee1\u8db3\uff0c\u5bfc\u81f4\u4e00\u76f4\u91cd\u590d\u5c1d\u8bd5\uff0c\u5931\u8d25\uff0c\u5c1d\u8bd5\uff0c\u5931\u8d25\u3002\u6d3b\u9501\u548c\u6b7b\u9501\u7684\u533a\u522b\u5728\u4e8e\uff0c\u5904\u4e8e\u6d3b\u9501\u7684\u5b9e\u4f53\u662f\u5728\u4e0d\u65ad\u7684\u6539\u53d8\u72b6\u6001\uff0c\u6240\u8c13\u7684\u201c\u6d3b\u201d\uff0c \u800c\u5904\u4e8e\u6b7b\u9501\u7684\u5b9e\u4f53\u8868\u73b0\u4e3a\u7b49\u5f85\uff1b\u6d3b\u9501\u6709\u53ef\u80fd\u81ea\u884c\u89e3\u5f00\uff0c\u6b7b\u9501\u5219\u4e0d\u80fd\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u9965\u997f\uff1a\u4e00\u4e2a\u6216\u8005\u591a\u4e2a\u7ebf\u7a0b\u56e0\u4e3a\u79cd\u79cd\u539f\u56e0\u65e0\u6cd5\u83b7\u5f97\u6240\u9700\u8981\u7684\u8d44\u6e90\uff0c\u5bfc\u81f4\u4e00\u76f4\u65e0\u6cd5\u6267\u884c\u7684\u72b6\u6001\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Java \u4e2d\u5bfc\u81f4\u9965\u997f\u7684\u539f\u56e0\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u9ad8\u4f18\u5148\u7ea7\u7ebf\u7a0b\u541e\u566c\u6240\u6709\u7684\u4f4e\u4f18\u5148\u7ea7\u7ebf\u7a0b\u7684 CPU \u65f6\u95f4\u3002<\/li><li>\u7ebf\u7a0b\u88ab\u6c38\u4e45\u5835\u585e\u5728\u4e00\u4e2a\u7b49\u5f85\u8fdb\u5165\u540c\u6b65\u5757\u7684\u72b6\u6001\uff0c\u56e0\u4e3a\u5176\u4ed6\u7ebf\u7a0b\u603b\u662f\u80fd\u5728\u5b83\u4e4b\u524d\u6301\u7eed\u5730\u5bf9\u8be5\u540c\u6b65\u5757\u8fdb\u884c\u8bbf\u95ee\u3002<\/li><li>\u7ebf\u7a0b\u5728\u7b49\u5f85\u4e00\u4e2a\u672c\u8eab\u4e5f\u5904\u4e8e\u6c38\u4e45\u7b49\u5f85\u5b8c\u6210\u7684\u5bf9\u8c61(\u6bd4\u5982\u8c03\u7528\u8fd9\u4e2a\u5bf9\u8c61\u7684 wait \u65b9\u6cd5)\uff0c\u56e0\u4e3a\u5176\u4ed6\u7ebf\u7a0b\u603b\u662f\u88ab\u6301\u7eed\u5730\u83b7\u5f97\u5524\u9192\u3002<\/li><\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">5\u3001Java \u4e2d\u7528\u5230\u7684\u7ebf\u7a0b\u8c03\u5ea6\u7b97\u6cd5\u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u91c7\u7528\u65f6\u95f4\u7247\u8f6e\u8f6c\u7684\u65b9\u5f0f\u3002\u53ef\u4ee5\u8bbe\u7f6e\u7ebf\u7a0b\u7684\u4f18\u5148\u7ea7\uff0c\u4f1a\u6620\u5c04\u5230\u4e0b\u5c42\u7684\u7cfb\u7edf\u4e0a\u9762\u7684\u4f18\u5148\u7ea7\u4e0a\uff0c\u5982\u975e\u7279\u522b\u9700\u8981\uff0c\u5c3d\u91cf\u4e0d\u8981\u7528\uff0c\u9632\u6b62\u7ebf\u7a0b\u9965\u997f\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">6\u3001\u4ec0\u4e48\u662f\u7ebf\u7a0b\u7ec4\uff0c\u4e3a\u4ec0\u4e48\u5728 Java \u4e2d\u4e0d\u63a8\u8350\u4f7f\u7528\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">ThreadGroup \u7c7b\uff0c\u53ef\u4ee5\u628a\u7ebf\u7a0b\u5f52\u5c5e\u5230\u67d0\u4e00\u4e2a\u7ebf\u7a0b\u7ec4\u4e2d\uff0c\u7ebf\u7a0b\u7ec4\u4e2d\u53ef\u4ee5\u6709\u7ebf\u7a0b\u5bf9\u8c61\uff0c\u4e5f\u53ef\u4ee5\u6709\u7ebf\u7a0b\u7ec4\uff0c\u7ec4\u4e2d\u8fd8\u53ef\u4ee5\u6709\u7ebf\u7a0b\uff0c\u8fd9\u6837\u7684\u7ec4\u7ec7\u7ed3\u6784\u6709\u70b9\u7c7b\u4f3c\u4e8e\u6811\u7684\u5f62\u5f0f\u3002\u4e3a\u4ec0\u4e48\u4e0d\u63a8\u8350\u4f7f\u7528\uff1f\u56e0\u4e3a\u4f7f\u7528\u6709\u5f88\u591a\u7684\u5b89\u5168\u9690\u60a3\u5427\uff0c\u6ca1\u6709\u5177\u4f53\u8ffd\u7a76\uff0c\u5982\u679c\u9700\u8981\u4f7f\u7528\uff0c\u63a8\u8350\u4f7f\u7528\u7ebf\u7a0b\u6c60\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">7\u3001\u4e3a\u4ec0\u4e48\u4f7f\u7528 Executor \u6846\u67b6\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6bcf\u6b21\u6267\u884c\u4efb\u52a1\u521b\u5efa\u7ebf\u7a0b new Thread()\u6bd4\u8f83\u6d88\u8017\u6027\u80fd\uff0c\u521b\u5efa\u4e00\u4e2a\u7ebf\u7a0b\u662f\u6bd4\u8f83\u8017\u65f6\u3001\u8017\u8d44\u6e90\u7684\u3002\u8c03\u7528 new Thread()\u521b\u5efa\u7684\u7ebf\u7a0b\u7f3a\u4e4f\u7ba1\u7406\uff0c\u88ab\u79f0\u4e3a\u91ce\u7ebf\u7a0b\uff0c\u800c\u4e14\u53ef\u4ee5\u65e0\u9650\u5236\u7684\u521b\u5efa\uff0c\u7ebf\u7a0b\u4e4b\u95f4\u7684\u76f8\u4e92\u7ade\u4e89\u4f1a\u5bfc\u81f4\u8fc7\u591a\u5360\u7528\u7cfb\u7edf\u8d44\u6e90\u800c\u5bfc\u81f4\u7cfb\u7edf\u762b\u75ea\uff0c\u8fd8\u6709\u7ebf\u7a0b\u4e4b\u95f4\u7684\u9891\u7e41\u4ea4\u66ff\u4e5f\u4f1a\u6d88\u8017\u5f88\u591a\u7cfb\u7edf\u8d44\u6e90\u3002\u63a5\u4f7f\u7528 new Thread() \u542f\u52a8\u7684\u7ebf\u7a0b\u4e0d\u5229\u4e8e\u6269\u5c55\uff0c\u6bd4\u5982\u5b9a\u65f6\u6267\u884c\u3001\u5b9a\u671f\u6267\u884c\u3001\u5b9a\u65f6\u5b9a\u671f\u6267\u884c\u3001\u7ebf\u7a0b\u4e2d\u65ad\u7b49\u90fd\u4e0d\u4fbf\u5b9e\u73b0\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">8\u3001\u5728 Java \u4e2d Executor \u548c Executors \u7684\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Executors \u5de5\u5177\u7c7b\u7684\u4e0d\u540c\u65b9\u6cd5\u6309\u7167\u6211\u4eec\u7684\u9700\u6c42\u521b\u5efa\u4e86\u4e0d\u540c\u7684\u7ebf\u7a0b\u6c60\uff0c\u6765\u6ee1\u8db3\u4e1a\u52a1\u7684\u9700\u6c42\u3002Executor \u63a5\u53e3\u5bf9\u8c61\u80fd\u6267\u884c\u6211\u4eec\u7684\u7ebf\u7a0b\u4efb\u52a1\u3002ExecutorService \u63a5\u53e3\u7ee7\u627f\u4e86 Executor \u63a5\u53e3\u5e76\u8fdb\u884c\u4e86\u6269\u5c55\uff0c\u63d0\u4f9b\u4e86\u66f4\u591a\u7684\u65b9\u6cd5\u6211\u4eec\u80fd\u83b7\u5f97\u4efb\u52a1\u6267\u884c\u7684\u72b6\u6001\u5e76\u4e14\u53ef\u4ee5\u83b7\u53d6\u4efb\u52a1\u7684\u8fd4\u56de\u503c\u3002\u4f7f\u7528 ThreadPoolExecutor \u53ef\u4ee5\u521b\u5efa\u81ea\u5b9a\u4e49\u7ebf\u7a0b\u6c60\u3002Future \u8868\u793a\u5f02\u6b65\u8ba1\u7b97\u7684\u7ed3\u679c\uff0c\u4ed6\u63d0\u4f9b\u4e86\u68c0\u67e5\u8ba1\u7b97\u662f\u5426\u5b8c\u6210\u7684\u65b9\u6cd5\uff0c\u4ee5\u7b49\u5f85\u8ba1\u7b97\u7684\u5b8c\u6210\uff0c\u5e76\u53ef\u4ee5\u4f7f\u7528 get()\u65b9\u6cd5\u83b7\u53d6\u8ba1\u7b97\u7684\u7ed3\u679c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">9\u3001\u5982\u4f55\u5524\u9192\u4e00\u4e2a\u963b\u585e\u7684\u7ebf\u7a0b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u56e0\u4e3a sleep\uff0cwait\uff0cjoin \u7b49\u963b\u585e\uff0c\u53ef\u4ee5\u4f7f\u7528 interrupted exception \u5f02\u5e38\u5524\u9192\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">10\u3001\u4ec0\u4e48\u662f\u539f\u5b50\u64cd\u4f5c\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728 Java Concurrency API \u4e2d\u6709\u54ea\u4e9b\u539f\u5b50\u7c7b(atomic classes)\uff1f\u539f\u5b50\u64cd\u4f5c\uff08atomic operation\uff09\u610f\u4e3a\u201d\u4e0d\u53ef\u88ab\u4e2d\u65ad\u7684\u4e00\u4e2a\u6216\u4e00\u7cfb\u5217\u64cd\u4f5c\u201d \u3002\u5904\u7406\u5668\u4f7f\u7528\u57fa\u4e8e\u5bf9\u7f13\u5b58\u52a0\u9501\u6216\u603b\u7ebf\u52a0\u9501\u7684\u65b9\u5f0f\u6765\u5b9e\u73b0\u591a\u5904\u7406\u5668\u4e4b\u95f4\u7684\u539f\u5b50\u64cd\u4f5c\u3002\u5728 Java \u4e2d\u53ef\u4ee5\u901a\u8fc7\u9501\u548c\u5faa\u73af CAS \u7684\u65b9\u5f0f\u6765\u5b9e\u73b0\u539f\u5b50\u64cd\u4f5c\u3002 CAS \u64cd\u4f5c\u2014\u2014Compare &amp; Set\uff0c\u6216\u662f Compare &amp; Swap\uff0c\u73b0\u5728\u51e0\u4e4e\u6240\u6709\u7684 CPU \u6307\u4ee4\u90fd\u652f\u6301 CAS\u7684\u539f\u5b50\u64cd\u4f5c\u3002\u539f\u5b50\u64cd\u4f5c\u662f\u6307\u4e00\u4e2a\u4e0d\u53d7\u5176\u4ed6\u64cd\u4f5c\u5f71\u54cd\u7684\u64cd\u4f5c\u4efb\u52a1\u5355\u5143\u3002\u539f\u5b50\u64cd\u4f5c\u662f\u5728\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\u907f\u514d\u6570\u636e\u4e0d\u4e00\u81f4\u5fc5\u987b\u7684\u624b\u6bb5\u3002int++\u5e76\u4e0d\u662f\u4e00\u4e2a\u539f\u5b50\u64cd\u4f5c\uff0c\u6240\u4ee5\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u8bfb\u53d6\u5b83\u7684\u503c\u5e76\u52a0 1 \u65f6\uff0c\u53e6\u5916\u4e00\u4e2a\u7ebf\u7a0b\u6709\u53ef\u80fd\u4f1a\u8bfb\u5230\u4e4b\u524d\u7684\u503c\uff0c\u8fd9\u5c31\u4f1a\u5f15\u53d1\u9519\u8bef\u3002\u4e3a\u4e86\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff0c\u5fc5\u987b\u4fdd\u8bc1\u589e\u52a0\u64cd\u4f5c\u662f\u539f\u5b50\u7684\uff0c\u5728 JDK1.5 \u4e4b\u524d\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u540c\u6b65\u6280\u672f\u6765\u505a\u5230\u8fd9\u4e00\u70b9\u3002\u5230 JDK1.5\uff0cjava.util.concurrent.atomic \u5305\u63d0\u4f9b\u4e86 int \u548clong \u7c7b\u578b\u7684\u539f\u5b50\u5305\u88c5\u7c7b\uff0c\u5b83\u4eec\u53ef\u4ee5\u81ea\u52a8\u7684\u4fdd\u8bc1\u5bf9\u4e8e\u4ed6\u4eec\u7684\u64cd\u4f5c\u662f\u539f\u5b50\u7684\u5e76\u4e14\u4e0d\u9700\u8981\u4f7f\u7528\u540c\u6b65\u3002java.util.concurrent \u8fd9\u4e2a\u5305\u91cc\u9762\u63d0\u4f9b\u4e86\u4e00\u7ec4\u539f\u5b50\u7c7b\u3002\u5176\u57fa\u672c\u7684\u7279\u6027\u5c31\u662f\u5728\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\uff0c\u5f53\u6709\u591a\u4e2a\u7ebf\u7a0b\u540c\u65f6\u6267\u884c\u8fd9\u4e9b\u7c7b\u7684\u5b9e\u4f8b\u5305\u542b\u7684\u65b9\u6cd5\u65f6\uff0c\u5177\u6709\u6392\u4ed6\u6027\uff0c\u5373\u5f53\u67d0\u4e2a\u7ebf\u7a0b\u8fdb\u5165\u65b9\u6cd5\uff0c\u6267\u884c\u5176\u4e2d\u7684\u6307\u4ee4\u65f6\uff0c\u4e0d\u4f1a\u88ab\u5176\u4ed6\u7ebf\u7a0b\u6253\u65ad\uff0c\u800c\u522b\u7684\u7ebf\u7a0b\u5c31\u50cf\u81ea\u65cb\u9501\u4e00\u6837\uff0c\u4e00\u76f4\u7b49\u5230\u8be5\u65b9\u6cd5\u6267\u884c\u5b8c\u6210\uff0c\u624d\u7531 JVM \u4ece\u7b49\u5f85\u961f\u5217\u4e2d\u9009\u62e9\u4e00\u4e2a\u53e6\u4e00\u4e2a\u7ebf\u7a0b\u8fdb\u5165\uff0c\u8fd9\u53ea\u662f\u4e00\u79cd\u903b\u8f91\u4e0a\u7684\u7406\u89e3\u3002\u539f\u5b50\u7c7b\uff1aAtomicBoolean\uff0cAtomicInteger\uff0cAtomicLong\uff0cAtomicReference\u539f\u5b50\u6570\u7ec4\uff1aAtomicIntegerArray\uff0cAtomicLongArray\uff0cAtomicReferenceArray\u539f\u5b50\u5c5e\u6027\u66f4\u65b0\u5668\uff1aAtomicLongFieldUpdater\uff0cAtomicIntegerFieldUpdater\uff0cAtomicReferenceFieldUpdater\u89e3\u51b3 ABA \u95ee\u9898\u7684\u539f\u5b50\u7c7b\uff1aAtomicMarkableReference\uff08\u901a\u8fc7\u5f15\u5165\u4e00\u4e2a boolean\u6765\u53cd\u6620\u4e2d\u95f4\u6709\u6ca1\u6709\u53d8\u8fc7\uff09\uff0cAtomicStampedReference\uff08\u901a\u8fc7\u5f15\u5165\u4e00\u4e2a int \u6765\u7d2f\u52a0\u6765\u53cd\u6620\u4e2d\u95f4\u6709\u6ca1\u6709\u53d8\u8fc7\uff09<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">11\u3001Java Concurrency API \u4e2d\u7684 Lock \u63a5\u53e3(Lock interface)\u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5bf9\u6bd4\u540c\u6b65\u5b83\u6709\u4ec0\u4e48\u4f18\u52bf\uff1fLock \u63a5\u53e3\u6bd4\u540c\u6b65\u65b9\u6cd5\u548c\u540c\u6b65\u5757\u63d0\u4f9b\u4e86\u66f4\u5177\u6269\u5c55\u6027\u7684\u9501\u64cd\u4f5c\u3002\u4ed6\u4eec\u5141\u8bb8\u66f4\u7075\u6d3b\u7684\u7ed3\u6784\uff0c\u53ef\u4ee5\u5177\u6709\u5b8c\u5168\u4e0d\u540c\u7684\u6027\u8d28\uff0c\u5e76\u4e14\u53ef\u4ee5\u652f\u6301\u591a\u4e2a\u76f8\u5173\u7c7b\u7684\u6761\u4ef6\u5bf9\u8c61\u3002\u5b83\u7684\u4f18\u52bf\u6709\uff1a\u53ef\u4ee5\u4f7f\u9501\u66f4\u516c\u5e73\u53ef\u4ee5\u4f7f\u7ebf\u7a0b\u5728\u7b49\u5f85\u9501\u7684\u65f6\u5019\u54cd\u5e94\u4e2d\u65ad\u53ef\u4ee5\u8ba9\u7ebf\u7a0b\u5c1d\u8bd5\u83b7\u53d6\u9501\uff0c\u5e76\u5728\u65e0\u6cd5\u83b7\u53d6\u9501\u7684\u65f6\u5019\u7acb\u5373\u8fd4\u56de\u6216\u8005\u7b49\u5f85\u4e00\u6bb5\u65f6\u95f4\u53ef\u4ee5\u5728\u4e0d\u540c\u7684\u8303\u56f4\uff0c\u4ee5\u4e0d\u540c\u7684\u987a\u5e8f\u83b7\u53d6\u548c\u91ca\u653e\u9501\u6574\u4f53\u4e0a\u6765\u8bf4 Lock \u662f synchronized \u7684\u6269\u5c55\u7248\uff0cLock \u63d0\u4f9b\u4e86\u65e0\u6761\u4ef6\u7684\u3001\u53ef\u8f6e\u8be2\u7684(tryLock \u65b9\u6cd5)\u3001\u5b9a\u65f6\u7684(tryLock \u5e26\u53c2\u65b9\u6cd5)\u3001\u53ef\u4e2d\u65ad\u7684(lockInterruptibly)\u3001\u53ef\u591a\u6761\u4ef6\u961f\u5217\u7684(newCondition \u65b9\u6cd5)\u9501\u64cd\u4f5c\u3002\u53e6\u5916 Lock \u7684\u5b9e\u73b0\u7c7b\u57fa\u672c\u90fd\u652f\u6301\u975e\u516c\u5e73\u9501(\u9ed8\u8ba4)\u548c\u516c\u5e73\u9501\uff0csynchronized \u53ea\u652f\u6301\u975e\u516c\u5e73\u9501\uff0c\u5f53\u7136\uff0c\u5728\u5927\u90e8\u5206\u60c5\u51b5\u4e0b\uff0c\u975e\u516c\u5e73\u9501\u662f\u9ad8\u6548\u7684\u9009\u62e9\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">12\u3001\u4ec0\u4e48\u662f Executors \u6846\u67b6\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Executor \u6846\u67b6\u662f\u4e00\u4e2a\u6839\u636e\u4e00\u7ec4\u6267\u884c\u7b56\u7565\u8c03\u7528\uff0c\u8c03\u5ea6\uff0c\u6267\u884c\u548c\u63a7\u5236\u7684\u5f02\u6b65\u4efb\u52a1\u7684\u6846\u67b6\u3002\u65e0\u9650\u5236\u7684\u521b\u5efa\u7ebf\u7a0b\u4f1a\u5f15\u8d77\u5e94\u7528\u7a0b\u5e8f\u5185\u5b58\u6ea2\u51fa\u3002\u6240\u4ee5\u521b\u5efa\u4e00\u4e2a\u7ebf\u7a0b\u6c60\u662f\u4e2a\u66f4\u597d\u7684\u7684\u89e3\u51b3\u65b9\u6848\uff0c\u56e0\u4e3a\u53ef\u4ee5\u9650\u5236\u7ebf\u7a0b\u7684\u6570\u91cf\u5e76\u4e14\u53ef\u4ee5\u56de\u6536\u518d\u5229\u7528\u8fd9\u4e9b\u7ebf\u7a0b\u3002\u5229\u7528Executors \u6846\u67b6\u53ef\u4ee5\u975e\u5e38\u65b9\u4fbf\u7684\u521b\u5efa\u4e00\u4e2a\u7ebf\u7a0b\u6c60\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">13\u3001\u4ec0\u4e48\u662f\u963b\u585e\u961f\u5217\uff1f\u963b\u585e\u961f\u5217\u7684\u5b9e\u73b0\u539f\u7406\u662f\u4ec0\u4e48\uff1f\u5982\u4f55\u4f7f\u7528\u963b\u585e\u961f\u5217\u6765\u5b9e\u73b0\u751f\u4ea7\u8005-\u6d88\u8d39\u8005\u6a21\u578b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u963b\u585e\u961f\u5217\uff08BlockingQueue\uff09\u662f\u4e00\u4e2a\u652f\u6301\u4e24\u4e2a\u9644\u52a0\u64cd\u4f5c\u7684\u961f\u5217\u3002\u8fd9\u4e24\u4e2a\u9644\u52a0\u7684\u64cd\u4f5c\u662f\uff1a\u5728\u961f\u5217\u4e3a\u7a7a\u65f6\uff0c\u83b7\u53d6\u5143\u7d20\u7684\u7ebf\u7a0b\u4f1a\u7b49\u5f85\u961f\u5217\u53d8\u4e3a\u975e\u7a7a\u3002\u5f53\u961f\u5217\u6ee1\u65f6\uff0c\u5b58\u50a8\u5143\u7d20\u7684\u7ebf\u7a0b\u4f1a\u7b49\u5f85\u961f\u5217\u53ef\u7528\u3002\u963b\u585e\u961f\u5217\u5e38\u7528\u4e8e\u751f\u4ea7\u8005\u548c\u6d88\u8d39\u8005\u7684\u573a\u666f\uff0c\u751f\u4ea7\u8005\u662f\u5f80\u961f\u5217\u91cc\u6dfb\u52a0\u5143\u7d20\u7684\u7ebf\u7a0b\uff0c\u6d88\u8d39\u8005\u662f\u4ece\u961f\u5217\u91cc\u62ff\u5143\u7d20\u7684\u7ebf\u7a0b\u3002\u963b\u585e\u961f\u5217\u5c31\u662f\u751f\u4ea7\u8005\u5b58\u653e\u5143\u7d20\u7684\u5bb9\u5668\uff0c\u800c\u6d88\u8d39\u8005\u4e5f\u53ea\u4ece\u5bb9\u5668\u91cc\u62ff\u5143\u7d20\u3002JDK7 \u63d0\u4f9b\u4e86 7 \u4e2a\u963b\u585e\u961f\u5217\u3002\u5206\u522b\u662f\uff1aArrayBlockingQueue \uff1a\u4e00\u4e2a\u7531\u6570\u7ec4\u7ed3\u6784\u7ec4\u6210\u7684\u6709\u754c\u963b\u585e\u961f\u5217\u3002LinkedBlockingQueue \uff1a\u4e00\u4e2a\u7531\u94fe\u8868\u7ed3\u6784\u7ec4\u6210\u7684\u6709\u754c\u963b\u585e\u961f\u5217\u3002PriorityBlockingQueue \uff1a\u4e00\u4e2a\u652f\u6301\u4f18\u5148\u7ea7\u6392\u5e8f\u7684\u65e0\u754c\u963b\u585e\u961f\u5217\u3002DelayQueue\uff1a\u4e00\u4e2a\u4f7f\u7528\u4f18\u5148\u7ea7\u961f\u5217\u5b9e\u73b0\u7684\u65e0\u754c\u963b\u585e\u961f\u5217\u3002SynchronousQueue\uff1a\u4e00\u4e2a\u4e0d\u5b58\u50a8\u5143\u7d20\u7684\u963b\u585e\u961f\u5217\u3002LinkedTransferQueue\uff1a\u4e00\u4e2a\u7531\u94fe\u8868\u7ed3\u6784\u7ec4\u6210\u7684\u65e0\u754c\u963b\u585e\u961f\u5217\u3002LinkedBlockingDeque\uff1a\u4e00\u4e2a\u7531\u94fe\u8868\u7ed3\u6784\u7ec4\u6210\u7684\u53cc\u5411\u963b\u585e\u961f\u5217\u3002Java 5 \u4e4b\u524d\u5b9e\u73b0\u540c\u6b65\u5b58\u53d6\u65f6\uff0c\u53ef\u4ee5\u4f7f\u7528\u666e\u901a\u7684\u4e00\u4e2a\u96c6\u5408\uff0c\u7136\u540e\u5728\u4f7f\u7528\u7ebf\u7a0b\u7684\u534f\u4f5c\u548c\u7ebf\u7a0b\u540c\u6b65\u53ef\u4ee5\u5b9e\u73b0\u751f\u4ea7\u8005\uff0c\u6d88\u8d39\u8005\u6a21\u5f0f\uff0c\u4e3b\u8981\u7684\u6280\u672f\u5c31\u662f\u7528\u597d\uff0cwait ,notify,notifyAll,sychronized \u8fd9\u4e9b\u5173\u952e\u5b57\u3002\u800c\u5728 java 5 \u4e4b\u540e\uff0c\u53ef\u4ee5\u4f7f\u7528\u963b\u585e\u961f\u5217\u6765\u5b9e\u73b0\uff0c\u6b64\u65b9\u5f0f\u5927\u5927\u7b80\u5c11\u4e86\u4ee3\u7801\u91cf\uff0c\u4f7f\u5f97\u591a\u7ebf\u7a0b\u7f16\u7a0b\u66f4\u52a0\u5bb9\u6613\uff0c\u5b89\u5168\u65b9\u9762\u4e5f\u6709\u4fdd\u969c\u3002BlockingQueue \u63a5\u53e3\u662f Queue \u7684\u5b50\u63a5\u53e3\uff0c\u5b83\u7684\u4e3b\u8981\u7528\u9014\u5e76\u4e0d\u662f\u4f5c\u4e3a\u5bb9\u5668\uff0c\u800c\u662f\u4f5c\u4e3a\u7ebf\u7a0b\u540c\u6b65\u7684\u7684\u5de5\u5177\uff0c\u56e0\u6b64\u4ed6\u5177\u6709\u4e00\u4e2a\u5f88\u660e\u663e\u7684\u7279\u6027\uff0c\u5f53\u751f\u4ea7\u8005\u7ebf\u7a0b\u8bd5\u56fe\u5411BlockingQueue \u653e\u5165\u5143\u7d20\u65f6\uff0c\u5982\u679c\u961f\u5217\u5df2\u6ee1\uff0c\u5219\u7ebf\u7a0b\u88ab\u963b\u585e\uff0c\u5f53\u6d88\u8d39\u8005\u7ebf\u7a0b\u8bd5\u56fe\u4ece\u4e2d\u53d6\u51fa\u4e00\u4e2a\u5143\u7d20\u65f6\uff0c\u5982\u679c\u961f\u5217\u4e3a\u7a7a\uff0c\u5219\u8be5\u7ebf\u7a0b\u4f1a\u88ab\u963b\u585e\uff0c\u6b63\u662f\u56e0\u4e3a\u5b83\u6240\u5177\u6709\u8fd9\u4e2a\u7279\u6027\uff0c\u6240\u4ee5\u5728\u7a0b\u5e8f\u4e2d\u591a\u4e2a\u7ebf\u7a0b\u4ea4\u66ff\u5411 BlockingQueue \u4e2d\u653e\u5165\u5143\u7d20\uff0c\u53d6\u51fa\u5143\u7d20\uff0c\u5b83\u53ef\u4ee5\u5f88\u597d\u7684\u63a7\u5236\u7ebf\u7a0b\u4e4b\u95f4\u7684\u901a\u4fe1\u3002\u963b\u585e\u961f\u5217\u4f7f\u7528\u6700\u7ecf\u5178\u7684\u573a\u666f\u5c31\u662f socket \u5ba2\u6237\u7aef\u6570\u636e\u7684\u8bfb\u53d6\u548c\u89e3\u6790\uff0c\u8bfb\u53d6\u6570\u636e\u7684\u7ebf\u7a0b\u4e0d\u65ad\u5c06\u6570\u636e\u653e\u5165\u961f\u5217\uff0c\u7136\u540e\u89e3\u6790\u7ebf\u7a0b\u4e0d\u65ad\u4ece\u961f\u5217\u53d6\u6570\u636e\u89e3\u6790\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">14\u3001\u4ec0\u4e48\u662f Callable \u548c Future?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Callable \u63a5\u53e3\u7c7b\u4f3c\u4e8e Runnable\uff0c\u4ece\u540d\u5b57\u5c31\u53ef\u4ee5\u770b\u51fa\u6765\u4e86\uff0c\u4f46\u662f Runnable \u4e0d\u4f1a\u8fd4\u56de\u7ed3\u679c\uff0c\u5e76\u4e14\u65e0\u6cd5\u629b\u51fa\u8fd4\u56de\u7ed3\u679c\u7684\u5f02\u5e38\uff0c\u800c Callable \u529f\u80fd\u66f4\u5f3a\u5927\u4e00\u4e9b\uff0c\u88ab\u7ebf\u7a0b\u6267\u884c\u540e\uff0c\u53ef\u4ee5\u8fd4\u56de\u503c\uff0c\u8fd9\u4e2a\u8fd4\u56de\u503c\u53ef\u4ee5\u88ab Future \u62ff\u5230\uff0c\u4e5f\u5c31\u662f\u8bf4\uff0cFuture \u53ef\u4ee5\u62ff\u5230\u5f02\u6b65\u6267\u884c\u4efb\u52a1\u7684\u8fd4\u56de\u503c\u3002\u53ef\u4ee5\u8ba4\u4e3a\u662f\u5e26\u6709\u56de\u8c03\u7684 Runnable\u3002Future \u63a5\u53e3\u8868\u793a\u5f02\u6b65\u4efb\u52a1\uff0c\u662f\u8fd8\u6ca1\u6709\u5b8c\u6210\u7684\u4efb\u52a1\u7ed9\u51fa\u7684\u672a\u6765\u7ed3\u679c\u3002\u6240\u4ee5\u8bf4 Callable\u7528\u4e8e\u4ea7\u751f\u7ed3\u679c\uff0cFuture \u7528\u4e8e\u83b7\u53d6\u7ed3\u679c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">15\u3001\u4ec0\u4e48\u662f FutureTask?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528 ExecutorService \u542f\u52a8\u4efb\u52a1\u3002\u5728 Java \u5e76\u53d1\u7a0b\u5e8f\u4e2d FutureTask \u8868\u793a\u4e00\u4e2a\u53ef\u4ee5\u53d6\u6d88\u7684\u5f02\u6b65\u8fd0\u7b97\u3002\u5b83\u6709\u542f\u52a8\u548c\u53d6\u6d88\u8fd0\u7b97\u3001\u67e5\u8be2\u8fd0\u7b97\u662f\u5426\u5b8c\u6210\u548c\u53d6\u56de\u8fd0\u7b97\u7ed3\u679c\u7b49\u65b9\u6cd5\u3002\u53ea\u6709\u5f53\u8fd0\u7b97\u5b8c\u6210\u7684\u65f6\u5019\u7ed3\u679c\u624d\u80fd\u53d6\u56de\uff0c\u5982\u679c\u8fd0\u7b97\u5c1a\u672a\u5b8c\u6210 get \u65b9\u6cd5\u5c06\u4f1a\u963b\u585e\u3002\u4e00\u4e2a FutureTask \u5bf9\u8c61\u53ef\u4ee5\u5bf9\u8c03\u7528\u4e86 Callable \u548c Runnable \u7684\u5bf9\u8c61\u8fdb\u884c\u5305\u88c5\uff0c\u7531\u4e8e FutureTask \u4e5f\u662f\u8c03\u7528\u4e86 Runnable\u63a5\u53e3\u6240\u4ee5\u5b83\u53ef\u4ee5\u63d0\u4ea4\u7ed9 Executor \u6765\u6267\u884c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">16\u3001\u4ec0\u4e48\u662f\u5e76\u53d1\u5bb9\u5668\u7684\u5b9e\u73b0\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f55\u4e3a\u540c\u6b65\u5bb9\u5668\uff1a\u53ef\u4ee5\u7b80\u5355\u5730\u7406\u89e3\u4e3a\u901a\u8fc7 synchronized \u6765\u5b9e\u73b0\u540c\u6b65\u7684\u5bb9\u5668\uff0c\u5982\u679c\u6709\u591a\u4e2a\u7ebf\u7a0b\u8c03\u7528\u540c\u6b65\u5bb9\u5668\u7684\u65b9\u6cd5\uff0c\u5b83\u4eec\u5c06\u4f1a\u4e32\u884c\u6267\u884c\u3002\u6bd4\u5982 Vector\uff0cHashtable\uff0c\u4ee5\u53ca Collections.synchronizedSet\uff0csynchronizedList \u7b49\u65b9\u6cd5\u8fd4\u56de\u7684\u5bb9\u5668\u3002\u53ef\u4ee5\u901a\u8fc7\u67e5\u770b Vector\uff0cHashtable \u7b49\u8fd9\u4e9b\u540c\u6b65\u5bb9\u5668\u7684\u5b9e\u73b0\u4ee3\u7801\uff0c\u53ef\u4ee5\u770b\u5230\u8fd9\u4e9b\u5bb9\u5668\u5b9e\u73b0\u7ebf\u7a0b\u5b89\u5168\u7684\u65b9\u5f0f\u5c31\u662f\u5c06\u5b83\u4eec\u7684\u72b6\u6001\u5c01\u88c5\u8d77\u6765\uff0c\u5e76\u5728\u9700\u8981\u540c\u6b65\u7684\u65b9\u6cd5\u4e0a\u52a0\u4e0a\u5173\u952e\u5b57 synchronized\u3002\u5e76\u53d1\u5bb9\u5668\u4f7f\u7528\u4e86\u4e0e\u540c\u6b65\u5bb9\u5668\u5b8c\u5168\u4e0d\u540c\u7684\u52a0\u9501\u7b56\u7565\u6765\u63d0\u4f9b\u66f4\u9ad8\u7684\u5e76\u53d1\u6027\u548c\u4f38\u7f29\u6027\uff0c\u4f8b\u5982\u5728 ConcurrentHashMap \u4e2d\u91c7\u7528\u4e86\u4e00\u79cd\u7c92\u5ea6\u66f4\u7ec6\u7684\u52a0\u9501\u673a\u5236\uff0c\u53ef\u4ee5\u79f0\u4e3a\u5206\u6bb5\u9501\uff0c\u5728\u8fd9\u79cd\u9501\u673a\u5236\u4e0b\uff0c\u5141\u8bb8\u4efb\u610f\u6570\u91cf\u7684\u8bfb\u7ebf\u7a0b\u5e76\u53d1\u5730\u8bbf\u95ee map\uff0c\u5e76\u4e14\u6267\u884c\u8bfb\u64cd\u4f5c\u7684\u7ebf\u7a0b\u548c\u5199\u64cd\u4f5c\u7684\u7ebf\u7a0b\u4e5f\u53ef\u4ee5\u5e76\u53d1\u7684\u8bbf\u95ee map\uff0c\u540c\u65f6\u5141\u8bb8\u4e00\u5b9a\u6570\u91cf\u7684\u5199\u64cd\u4f5c\u7ebf\u7a0b\u5e76\u53d1\u5730\u4fee\u6539 map\uff0c\u6240\u4ee5\u5b83\u53ef\u4ee5\u5728\u5e76\u53d1\u73af\u5883\u4e0b\u5b9e\u73b0\u66f4\u9ad8\u7684\u541e\u5410\u91cf\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">17\u3001\u591a\u7ebf\u7a0b\u540c\u6b65\u548c\u4e92\u65a5\u6709\u51e0\u79cd\u5b9e\u73b0\u65b9\u6cd5\uff0c\u90fd\u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ebf\u7a0b\u540c\u6b65\u662f\u6307\u7ebf\u7a0b\u4e4b\u95f4\u6240\u5177\u6709\u7684\u4e00\u79cd\u5236\u7ea6\u5173\u7cfb\uff0c\u4e00\u4e2a\u7ebf\u7a0b\u7684\u6267\u884c\u4f9d\u8d56\u53e6\u4e00\u4e2a\u7ebf\u7a0b\u7684\u6d88\u606f\uff0c\u5f53\u5b83\u6ca1\u6709\u5f97\u5230\u53e6\u4e00\u4e2a\u7ebf\u7a0b\u7684\u6d88\u606f\u65f6\u5e94\u7b49\u5f85\uff0c\u76f4\u5230\u6d88\u606f\u5230\u8fbe\u65f6\u624d\u88ab\u5524\u9192\u3002\u7ebf\u7a0b\u4e92\u65a5\u662f\u6307\u5bf9\u4e8e\u5171\u4eab\u7684\u8fdb\u7a0b\u7cfb\u7edf\u8d44\u6e90\uff0c\u5728\u5404\u5355\u4e2a\u7ebf\u7a0b\u8bbf\u95ee\u65f6\u7684\u6392\u5b83\u6027\u3002\u5f53\u6709\u82e5\u5e72\u4e2a\u7ebf\u7a0b\u90fd\u8981\u4f7f\u7528\u67d0\u4e00\u5171\u4eab\u8d44\u6e90\u65f6\uff0c\u4efb\u4f55\u65f6\u523b\u6700\u591a\u53ea\u5141\u8bb8\u4e00\u4e2a\u7ebf\u7a0b\u53bb\u4f7f\u7528\uff0c\u5176\u5b83\u8981\u4f7f\u7528\u8be5\u8d44\u6e90\u7684\u7ebf\u7a0b\u5fc5\u987b\u7b49\u5f85\uff0c\u76f4\u5230\u5360\u7528\u8d44\u6e90\u8005\u91ca\u653e\u8be5\u8d44\u6e90\u3002\u7ebf\u7a0b\u4e92\u65a5\u53ef\u4ee5\u770b\u6210\u662f\u4e00\u79cd\u7279\u6b8a\u7684\u7ebf\u7a0b\u540c\u6b65\u3002\u7ebf\u7a0b\u95f4\u7684\u540c\u6b65\u65b9\u6cd5\u5927\u4f53\u53ef\u5206\u4e3a\u4e24\u7c7b\uff1a\u7528\u6237\u6a21\u5f0f\u548c\u5185\u6838\u6a21\u5f0f\u3002\u987e\u540d\u601d\u4e49\uff0c\u5185\u6838\u6a21\u5f0f\u5c31\u662f\u6307\u5229\u7528\u7cfb\u7edf\u5185\u6838\u5bf9\u8c61\u7684\u5355\u4e00\u6027\u6765\u8fdb\u884c\u540c\u6b65\uff0c\u4f7f\u7528\u65f6\u9700\u8981\u5207\u6362\u5185\u6838\u6001\u4e0e\u7528\u6237\u6001\uff0c\u800c\u7528\u6237\u6a21\u5f0f\u5c31\u662f\u4e0d\u9700\u8981\u5207\u6362\u5230\u5185\u6838\u6001\uff0c\u53ea\u5728\u7528\u6237\u6001\u5b8c\u6210\u64cd\u4f5c\u3002\u7528\u6237\u6a21\u5f0f\u4e0b\u7684\u65b9\u6cd5\u6709\uff1a\u539f\u5b50\u64cd\u4f5c\uff08\u4f8b\u5982\u4e00\u4e2a\u5355\u4e00\u7684\u5168\u5c40\u53d8\u91cf\uff09\uff0c\u4e34\u754c\u533a\u3002\u5185\u6838\u6a21\u5f0f\u4e0b\u7684\u65b9\u6cd5\u6709\uff1a\u4e8b\u4ef6\uff0c\u4fe1\u53f7\u91cf\uff0c\u4e92\u65a5\u91cf\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">18\u3001\u4ec0\u4e48\u662f\u7ade\u4e89\u6761\u4ef6\uff1f\u4f60\u600e\u6837\u53d1\u73b0\u548c\u89e3\u51b3\u7ade\u4e89\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u591a\u4e2a\u8fdb\u7a0b\u90fd\u4f01\u56fe\u5bf9\u5171\u4eab\u6570\u636e\u8fdb\u884c\u67d0\u79cd\u5904\u7406\uff0c\u800c\u6700\u540e\u7684\u7ed3\u679c\u53c8\u53d6\u51b3\u4e8e\u8fdb\u7a0b\u8fd0\u884c\u7684\u987a\u5e8f\u65f6\uff0c\u5219\u6211\u4eec\u8ba4\u4e3a\u8fd9\u53d1\u751f\u4e86\u7ade\u4e89\u6761\u4ef6\uff08race condition\uff09\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">19\u3001\u4f60\u5c06\u5982\u4f55\u4f7f\u7528 thread dump\uff1f\u4f60\u5c06\u5982\u4f55\u5206\u6790 Thread dump\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u65b0\u5efa\u72b6\u6001\uff08New\uff09\u7528 new \u8bed\u53e5\u521b\u5efa\u7684\u7ebf\u7a0b\u5904\u4e8e\u65b0\u5efa\u72b6\u6001\uff0c\u6b64\u65f6\u5b83\u548c\u5176\u4ed6 Java \u5bf9\u8c61\u4e00\u6837\uff0c\u4ec5\u4ec5\u5728\u5806\u533a\u4e2d\u88ab\u5206\u914d\u4e86\u5185\u5b58\u3002\u5c31\u7eea\u72b6\u6001\uff08Runnable\uff09\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u5bf9\u8c61\u521b\u5efa\u540e\uff0c\u5176\u4ed6\u7ebf\u7a0b\u8c03\u7528\u5b83\u7684 start()\u65b9\u6cd5\uff0c\u8be5\u7ebf\u7a0b\u5c31\u8fdb\u5165\u5c31\u7eea\u72b6\u6001\uff0cJava \u865a\u62df\u673a\u4f1a\u4e3a\u5b83\u521b\u5efa\u65b9\u6cd5\u8c03\u7528\u6808\u548c\u7a0b\u5e8f\u8ba1\u6570\u5668\u3002\u5904\u4e8e\u8fd9\u4e2a\u72b6\u6001\u7684\u7ebf\u7a0b\u4f4d\u4e8e\u53ef\u8fd0\u884c\u6c60\u4e2d\uff0c\u7b49\u5f85\u83b7\u5f97 CPU \u7684\u4f7f\u7528\u6743\u3002\u8fd0\u884c\u72b6\u6001\uff08Running\uff09\u5904\u4e8e\u8fd9\u4e2a\u72b6\u6001\u7684\u7ebf\u7a0b\u5360\u7528 CPU\uff0c\u6267\u884c\u7a0b\u5e8f\u4ee3\u7801\u3002\u53ea\u6709\u5904\u4e8e\u5c31\u7eea\u72b6\u6001\u7684\u7ebf\u7a0b\u624d\u6709\u673a\u4f1a\u8f6c\u5230\u8fd0\u884c\u72b6\u6001\u3002\u963b\u585e\u72b6\u6001\uff08Blocked\uff09\u963b\u585e\u72b6\u6001\u662f\u6307\u7ebf\u7a0b\u56e0\u4e3a\u67d0\u4e9b\u539f\u56e0\u653e\u5f03 CPU\uff0c\u6682\u65f6\u505c\u6b62\u8fd0\u884c\u3002\u5f53\u7ebf\u7a0b\u5904\u4e8e\u963b\u585e\u72b6\u6001\u65f6\uff0cJava \u865a\u62df\u673a\u4e0d\u4f1a\u7ed9\u7ebf\u7a0b\u5206\u914d CPU\u3002\u76f4\u5230\u7ebf\u7a0b\u91cd\u65b0\u8fdb\u5165\u5c31\u7eea\u72b6\u6001\uff0c\u5b83\u624d\u6709\u673a\u4f1a\u8f6c\u5230\u8fd0\u884c\u72b6\u6001\u3002\u963b\u585e\u72b6\u6001\u53ef\u5206\u4e3a\u4ee5\u4e0b 3 \u79cd\uff1a\u4f4d\u4e8e\u5bf9\u8c61\u7b49\u5f85\u6c60\u4e2d\u7684\u963b\u585e\u72b6\u6001\uff08Blocked in object\u2019s wait pool\uff09\uff1a\u5f53\u7ebf\u7a0b\u5904\u4e8e\u8fd0\u884c\u72b6\u6001\u65f6\uff0c\u5982\u679c\u6267\u884c\u4e86\u67d0\u4e2a\u5bf9\u8c61\u7684 wait()\u65b9\u6cd5\uff0cJava \u865a\u62df\u673a\u5c31\u4f1a\u628a\u7ebf\u7a0b\u653e\u5230\u8fd9\u4e2a\u5bf9\u8c61\u7684\u7b49\u5f85\u6c60\u4e2d\uff0c\u8fd9\u6d89\u53ca\u5230\u201c\u7ebf\u7a0b\u901a\u4fe1\u201d\u7684\u5185\u5bb9\u3002\u4f4d\u4e8e\u5bf9\u8c61\u9501\u6c60\u4e2d\u7684\u963b\u585e\u72b6\u6001\uff08Blocked in object\u2019s lock pool\uff09\uff1a\u5f53\u7ebf\u7a0b\u5904\u4e8e\u8fd0\u884c\u72b6\u6001\u65f6\uff0c\u8bd5\u56fe\u83b7\u5f97\u67d0\u4e2a\u5bf9\u8c61\u7684\u540c\u6b65\u9501\u65f6\uff0c\u5982\u679c\u8be5\u5bf9\u8c61\u7684\u540c\u6b65\u9501\u5df2\u7ecf\u88ab\u5176\u4ed6\u7ebf\u7a0b\u5360\u7528\uff0cJava \u865a\u62df\u673a\u5c31\u4f1a\u628a\u8fd9\u4e2a\u7ebf\u7a0b\u653e\u5230\u8fd9\u4e2a\u5bf9\u8c61\u7684\u9501\u6c60\u4e2d\uff0c\u8fd9\u6d89\u53ca\u5230\u201c\u7ebf\u7a0b\u540c\u6b65\u201d\u7684\u5185\u5bb9\u3002\u5176\u4ed6\u963b\u585e\u72b6\u6001\uff08Otherwise Blocked\uff09\uff1a\u5f53\u524d\u7ebf\u7a0b\u6267\u884c\u4e86 sleep()\u65b9\u6cd5\uff0c\u6216\u8005\u8c03\u7528\u4e86\u5176\u4ed6\u7ebf\u7a0b\u7684 join()\u65b9\u6cd5\uff0c\u6216\u8005\u53d1\u51fa\u4e86 I\/O\u8bf7\u6c42\u65f6\uff0c\u5c31\u4f1a\u8fdb\u5165\u8fd9\u4e2a\u72b6\u6001\u3002\u6b7b\u4ea1\u72b6\u6001\uff08Dead\uff09\u5f53\u7ebf\u7a0b\u9000\u51fa run()\u65b9\u6cd5\u65f6\uff0c\u5c31\u8fdb\u5165\u6b7b\u4ea1\u72b6\u6001\uff0c\u8be5\u7ebf\u7a0b\u7ed3\u675f\u751f\u547d\u5468\u671f\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">20\u3001\u4e3a\u4ec0\u4e48\u6211\u4eec\u8c03\u7528 start()\u65b9\u6cd5\u65f6\u4f1a\u6267\u884c run()\u65b9\u6cd5\uff0c\u4e3a\u4ec0\u4e48\u6211\u4eec\u4e0d\u80fd\u76f4\u63a5\u8c03\u7528 run()\u65b9\u6cd5\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u4f60\u8c03\u7528 start()\u65b9\u6cd5\u65f6\u4f60\u5c06\u521b\u5efa\u65b0\u7684\u7ebf\u7a0b\uff0c\u5e76\u4e14\u6267\u884c\u5728 run()\u65b9\u6cd5\u91cc\u7684\u4ee3\u7801\u3002\u4f46\u662f\u5982\u679c\u4f60\u76f4\u63a5\u8c03\u7528 run()\u65b9\u6cd5\uff0c\u5b83\u4e0d\u4f1a\u521b\u5efa\u65b0\u7684\u7ebf\u7a0b\u4e5f\u4e0d\u4f1a\u6267\u884c\u8c03\u7528\u7ebf\u7a0b\u7684\u4ee3\u7801\uff0c\u53ea\u4f1a\u628a run \u65b9\u6cd5\u5f53\u4f5c\u666e\u901a\u65b9\u6cd5\u53bb\u6267\u884c\u300221\u3001Java \u4e2d\u4f60\u600e\u6837\u5524\u9192\u4e00\u4e2a\u963b\u585e\u7684\u7ebf\u7a0b\uff1f\u5728 Java \u53d1\u5c55\u53f2\u4e0a\u66fe\u7ecf\u4f7f\u7528 suspend()\u3001resume()\u65b9\u6cd5\u5bf9\u4e8e\u7ebf\u7a0b\u8fdb\u884c\u963b\u585e\u5524\u9192\uff0c\u4f46\u968f\u4e4b\u51fa\u73b0\u5f88\u591a\u95ee\u9898\uff0c\u6bd4\u8f83\u5178\u578b\u7684\u8fd8\u662f\u6b7b\u9501\u95ee\u9898\u3002\u89e3\u51b3\u65b9\u6848\u53ef\u4ee5\u4f7f\u7528\u4ee5\u5bf9\u8c61\u4e3a\u76ee\u6807\u7684\u963b\u585e\uff0c\u5373\u5229\u7528 Object \u7c7b\u7684 wait()\u548c notify()\u65b9\u6cd5\u5b9e\u73b0\u7ebf\u7a0b\u963b\u585e\u3002\u9996 \u5148 \uff0cwait\u3001notify \u65b9\u6cd5\u662f\u9488\u5bf9\u5bf9\u8c61\u7684\uff0c\u8c03\u7528\u4efb\u610f\u5bf9\u8c61\u7684 wait()\u65b9\u6cd5\u90fd\u5c06\u5bfc\u81f4\u7ebf\u7a0b\u963b\u585e\uff0c\u963b\u585e\u7684\u540c\u65f6\u4e5f\u5c06\u91ca\u653e\u8be5\u5bf9\u8c61\u7684\u9501\uff0c\u76f8\u5e94\u5730\uff0c\u8c03\u7528\u4efb\u610f\u5bf9\u8c61\u7684 notify()\u65b9\u6cd5\u5219\u5c06\u968f\u673a\u89e3\u9664\u8be5\u5bf9\u8c61\u963b\u585e\u7684\u7ebf\u7a0b\uff0c\u4f46\u5b83\u9700\u8981\u91cd\u65b0\u83b7\u53d6\u6539\u5bf9\u8c61\u7684\u9501\uff0c\u76f4\u5230\u83b7\u53d6\u6210\u529f\u624d\u80fd\u5f80\u4e0b\u6267\u884c\uff1b\u5176\u6b21\uff0cwait\u3001notify \u65b9\u6cd5\u5fc5\u987b\u5728 synchronized \u5757\u6216\u65b9\u6cd5\u4e2d\u88ab\u8c03\u7528\uff0c\u5e76\u4e14\u8981\u4fdd\u8bc1\u540c\u6b65\u5757\u6216\u65b9\u6cd5\u7684\u9501\u5bf9\u8c61\u4e0e\u8c03\u7528 wait\u3001notify \u65b9\u6cd5\u7684\u5bf9\u8c61\u662f\u540c\u4e00\u4e2a\uff0c\u5982\u6b64\u4e00\u6765\u5728\u8c03\u7528 wait \u4e4b\u524d\u5f53\u524d\u7ebf\u7a0b\u5c31\u5df2\u7ecf\u6210\u529f\u83b7\u53d6\u67d0\u5bf9\u8c61\u7684\u9501\uff0c\u6267\u884c wait \u963b\u585e\u540e\u5f53\u524d\u7ebf\u7a0b\u5c31\u5c06\u4e4b\u524d\u83b7\u53d6\u7684\u5bf9\u8c61\u9501\u91ca\u653e\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">22\u3001\u5728 Java \u4e2d CycliBarriar \u548c CountdownLatch \u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">CyclicBarrier \u53ef\u4ee5\u91cd\u590d\u4f7f\u7528\uff0c\u800c CountdownLatch \u4e0d\u80fd\u91cd\u590d\u4f7f\u7528\u3002Java \u7684 concurrent \u5305\u91cc\u9762\u7684 CountDownLatch \u5176\u5b9e\u53ef\u4ee5\u628a\u5b83\u770b\u4f5c\u4e00\u4e2a\u8ba1\u6570\u5668\uff0c\u53ea\u4e0d\u8fc7\u8fd9\u4e2a\u8ba1\u6570\u5668\u7684\u64cd\u4f5c\u662f\u539f\u5b50\u64cd\u4f5c\uff0c\u540c\u65f6\u53ea\u80fd\u6709\u4e00\u4e2a\u7ebf\u7a0b\u53bb\u64cd\u4f5c\u8fd9\u4e2a\u8ba1\u6570\u5668\uff0c\u4e5f\u5c31\u662f\u540c\u65f6\u53ea\u80fd\u6709\u4e00\u4e2a\u7ebf\u7a0b\u53bb\u51cf\u8fd9\u4e2a\u8ba1\u6570\u5668\u91cc\u9762\u7684\u503c\u3002\u4f60\u53ef\u4ee5\u5411 CountDownLatch \u5bf9\u8c61\u8bbe\u7f6e\u4e00\u4e2a\u521d\u59cb\u7684\u6570\u5b57\u4f5c\u4e3a\u8ba1\u6570\u503c\uff0c\u4efb\u4f55\u8c03\u7528\u8fd9\u4e2a\u5bf9\u8c61\u4e0a\u7684 await()\u65b9\u6cd5\u90fd\u4f1a\u963b\u585e\uff0c\u76f4\u5230\u8fd9\u4e2a\u8ba1\u6570\u5668\u7684\u8ba1\u6570\u503c\u88ab\u5176\u4ed6\u7684\u7ebf\u7a0b\u51cf\u4e3a 0 \u4e3a\u6b62\u3002\u6240\u4ee5\u5728\u5f53\u524d\u8ba1\u6570\u5230\u8fbe\u96f6\u4e4b\u524d\uff0cawait \u65b9\u6cd5\u4f1a\u4e00\u76f4\u53d7\u963b\u585e\u3002\u4e4b\u540e\uff0c\u4f1a\u91ca\u653e\u6240\u6709\u7b49\u5f85\u7684\u7ebf\u7a0b\uff0cawait \u7684\u6240\u6709\u540e\u7eed\u8c03\u7528\u90fd\u5c06\u7acb\u5373\u8fd4\u56de\u3002\u8fd9\u79cd\u73b0\u8c61\u53ea\u51fa\u73b0\u4e00\u6b21\u2014\u2014\u8ba1\u6570\u65e0\u6cd5\u88ab\u91cd\u7f6e\u3002\u5982\u679c\u9700\u8981\u91cd\u7f6e\u8ba1\u6570\uff0c\u8bf7\u8003\u8651\u4f7f\u7528 CyclicBarrier\u3002CountDownLatch \u7684\u4e00\u4e2a\u975e\u5e38\u5178\u578b\u7684\u5e94\u7528\u573a\u666f\u662f\uff1a\u6709\u4e00\u4e2a\u4efb\u52a1\u60f3\u8981\u5f80\u4e0b\u6267\u884c\uff0c\u4f46\u5fc5\u987b\u8981\u7b49\u5230\u5176\u4ed6\u7684\u4efb\u52a1\u6267\u884c\u5b8c\u6bd5\u540e\u624d\u53ef\u4ee5\u7ee7\u7eed\u5f80\u4e0b\u6267\u884c\u3002\u5047\u5982\u6211\u4eec\u8fd9\u4e2a\u60f3\u8981\u7ee7\u7eed\u5f80\u4e0b\u6267\u884c\u7684\u4efb\u52a1\u8c03\u7528\u4e00\u4e2a CountDownLatch \u5bf9\u8c61\u7684 await()\u65b9\u6cd5\uff0c\u5176\u4ed6\u7684\u4efb\u52a1\u6267\u884c\u5b8c\u81ea\u5df1\u7684\u4efb\u52a1\u540e\u8c03\u7528\u540c\u4e00\u4e2a CountDownLatch \u5bf9\u8c61\u4e0a\u7684 countDown()\u65b9\u6cd5\uff0c\u8fd9\u4e2a\u8c03\u7528 await()\u65b9\u6cd5\u7684\u4efb\u52a1\u5c06\u4e00\u76f4\u963b\u585e\u7b49\u5f85\uff0c\u76f4\u5230\u8fd9\u4e2a CountDownLatch \u5bf9\u8c61\u7684\u8ba1\u6570\u503c\u51cf\u5230 0 \u4e3a\u6b62\u3002CyclicBarrier \u4e00\u4e2a\u540c\u6b65\u8f85\u52a9\u7c7b\uff0c\u5b83\u5141\u8bb8\u4e00\u7ec4\u7ebf\u7a0b\u4e92\u76f8\u7b49\u5f85\uff0c\u76f4\u5230\u5230\u8fbe\u67d0\u4e2a\u516c\u5171\u5c4f\u969c\u70b9 (common barrier point)\u3002\u5728\u6d89\u53ca\u4e00\u7ec4\u56fa\u5b9a\u5927\u5c0f\u7684\u7ebf\u7a0b\u7684\u7a0b\u5e8f\u4e2d\uff0c\u8fd9\u4e9b\u7ebf\u7a0b\u5fc5\u987b\u4e0d\u65f6\u5730\u4e92\u76f8\u7b49\u5f85\uff0c\u6b64\u65f6 CyclicBarrier \u5f88\u6709\u7528\u3002\u56e0\u4e3a\u8be5 barrier \u5728\u91ca\u653e\u7b49\u5f85\u7ebf\u7a0b\u540e\u53ef\u4ee5\u91cd\u7528\uff0c\u6240\u4ee5\u79f0\u5b83\u4e3a\u5faa\u73af \u7684 barrier\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">23\u3001\u4ec0\u4e48\u662f\u4e0d\u53ef\u53d8\u5bf9\u8c61\uff0c\u5b83\u5bf9\u5199\u5e76\u53d1\u5e94\u7528\u6709\u4ec0\u4e48\u5e2e\u52a9\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0d\u53ef\u53d8\u5bf9\u8c61(Immutable Objects)\u5373\u5bf9\u8c61\u4e00\u65e6\u88ab\u521b\u5efa\u5b83\u7684\u72b6\u6001\uff08\u5bf9\u8c61\u7684\u6570\u636e\uff0c\u4e5f\u5373\u5bf9\u8c61\u5c5e\u6027\u503c\uff09\u5c31\u4e0d\u80fd\u6539\u53d8\uff0c\u53cd\u4e4b\u5373\u4e3a\u53ef\u53d8\u5bf9\u8c61(Mutable Objects)\u3002\u4e0d\u53ef\u53d8\u5bf9\u8c61\u7684\u7c7b\u5373\u4e3a\u4e0d\u53ef\u53d8\u7c7b(Immutable Class)\u3002Java \u5e73\u53f0\u7c7b\u5e93\u4e2d\u5305\u542b\u8bb8\u591a\u4e0d\u53ef\u53d8\u7c7b\uff0c\u5982 String\u3001\u57fa\u672c\u7c7b\u578b\u7684\u5305\u88c5\u7c7b\u3001BigInteger \u548c BigDecimal \u7b49\u3002\u4e0d\u53ef\u53d8\u5bf9\u8c61\u5929\u751f\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\u3002\u5b83\u4eec\u7684\u5e38\u91cf\uff08\u57df\uff09\u662f\u5728\u6784\u9020\u51fd\u6570\u4e2d\u521b\u5efa\u7684\u3002\u65e2\u7136\u5b83\u4eec\u7684\u72b6\u6001\u65e0\u6cd5\u4fee\u6539\uff0c\u8fd9\u4e9b\u5e38\u91cf\u6c38\u8fdc\u4e0d\u4f1a\u53d8\u3002\u4e0d\u53ef\u53d8\u5bf9\u8c61\u6c38\u8fdc\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\u3002\u53ea\u6709\u6ee1\u8db3\u5982\u4e0b\u72b6\u6001\uff0c\u4e00\u4e2a\u5bf9\u8c61\u624d\u662f\u4e0d\u53ef\u53d8\u7684\uff1b\u5b83\u7684\u72b6\u6001\u4e0d\u80fd\u5728\u521b\u5efa\u540e\u518d\u88ab\u4fee\u6539\uff1b\u6240\u6709\u57df\u90fd\u662f final \u7c7b\u578b\uff1b\u5e76\u4e14\uff0c\u5b83\u88ab\u6b63\u786e\u521b\u5efa\uff08\u521b\u5efa\u671f\u95f4\u6ca1\u6709\u53d1\u751f this \u5f15\u7528\u7684\u9038\u51fa\uff09\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">24\u3001\u4ec0\u4e48\u662f\u591a\u7ebf\u7a0b\u4e2d\u7684\u4e0a\u4e0b\u6587\u5207\u6362\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u4e0a\u4e0b\u6587\u5207\u6362\u8fc7\u7a0b\u4e2d\uff0cCPU \u4f1a\u505c\u6b62\u5904\u7406\u5f53\u524d\u8fd0\u884c\u7684\u7a0b\u5e8f\uff0c\u5e76\u4fdd\u5b58\u5f53\u524d\u7a0b\u5e8f\u8fd0\u884c\u7684\u5177\u4f53\u4f4d\u7f6e\u4ee5\u4fbf\u4e4b\u540e\u7ee7\u7eed\u8fd0\u884c\u3002\u4ece\u8fd9\u4e2a\u89d2\u5ea6\u6765\u770b\uff0c\u4e0a\u4e0b\u6587\u5207\u6362\u6709\u70b9\u50cf\u6211\u4eec\u540c\u65f6\u9605\u8bfb\u51e0\u672c\u4e66\uff0c\u5728\u6765\u56de\u5207\u6362\u4e66\u672c\u7684\u540c\u65f6\u6211\u4eec\u9700\u8981\u8bb0\u4f4f\u6bcf\u672c\u4e66\u5f53\u524d\u8bfb\u5230\u7684\u9875\u7801\u3002\u5728\u7a0b\u5e8f\u4e2d\uff0c\u4e0a\u4e0b\u6587\u5207\u6362\u8fc7\u7a0b\u4e2d\u7684\u201c\u9875\u7801\u201d\u4fe1\u606f\u662f\u4fdd\u5b58\u5728\u8fdb\u7a0b\u63a7\u5236\u5757\uff08PCB\uff09\u4e2d\u7684\u3002PCB \u8fd8\u7ecf\u5e38\u88ab\u79f0\u4f5c\u201c\u5207\u6362\u6862\u201d\uff08switchframe\uff09\u3002\u201c\u9875\u7801\u201d\u4fe1\u606f\u4f1a\u4e00\u76f4\u4fdd\u5b58\u5230 CPU \u7684\u5185\u5b58\u4e2d\uff0c\u76f4\u5230\u4ed6\u4eec\u88ab\u518d\u6b21\u4f7f\u7528\u3002\u4e0a\u4e0b\u6587\u5207\u6362\u662f\u5b58\u50a8\u548c\u6062\u590d CPU \u72b6\u6001\u7684\u8fc7\u7a0b\uff0c\u5b83\u4f7f\u5f97\u7ebf\u7a0b\u6267\u884c\u80fd\u591f\u4ece\u4e2d\u65ad\u70b9\u6062\u590d\u6267\u884c\u3002\u4e0a\u4e0b\u6587\u5207\u6362\u662f\u591a\u4efb\u52a1\u64cd\u4f5c\u7cfb\u7edf\u548c\u591a\u7ebf\u7a0b\u73af\u5883\u7684\u57fa\u672c\u7279\u5f81\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">25\u3001Java \u4e2d\u7528\u5230\u7684\u7ebf\u7a0b\u8c03\u5ea6\u7b97\u6cd5\u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8ba1\u7b97\u673a\u901a\u5e38\u53ea\u6709\u4e00\u4e2a CPU,\u5728\u4efb\u610f\u65f6\u523b\u53ea\u80fd\u6267\u884c\u4e00\u6761\u673a\u5668\u6307\u4ee4,\u6bcf\u4e2a\u7ebf\u7a0b\u53ea\u6709\u83b7\u5f97CPU \u7684\u4f7f\u7528\u6743\u624d\u80fd\u6267\u884c\u6307\u4ee4.\u6240\u8c13\u591a\u7ebf\u7a0b\u7684\u5e76\u53d1\u8fd0\u884c,\u5176\u5b9e\u662f\u6307\u4ece\u5b8f\u89c2\u4e0a\u770b,\u5404\u4e2a\u7ebf\u7a0b\u8f6e\u6d41\u83b7\u5f97 CPU \u7684\u4f7f\u7528\u6743,\u5206\u522b\u6267\u884c\u5404\u81ea\u7684\u4efb\u52a1.\u5728\u8fd0\u884c\u6c60\u4e2d,\u4f1a\u6709\u591a\u4e2a\u5904\u4e8e\u5c31\u7eea\u72b6\u6001\u7684\u7ebf\u7a0b\u5728\u7b49\u5f85 CPU,JAVA \u865a\u62df\u673a\u7684\u4e00\u9879\u4efb\u52a1\u5c31\u662f\u8d1f\u8d23\u7ebf\u7a0b\u7684\u8c03\u5ea6,\u7ebf\u7a0b\u8c03\u5ea6\u662f\u6307\u6309\u7167\u7279\u5b9a\u673a\u5236\u4e3a\u591a\u4e2a\u7ebf\u7a0b\u5206\u914d CPU \u7684\u4f7f\u7528\u6743.\u6709\u4e24\u79cd\u8c03\u5ea6\u6a21\u578b\uff1a\u5206\u65f6\u8c03\u5ea6\u6a21\u578b\u548c\u62a2\u5360\u5f0f\u8c03\u5ea6\u6a21\u578b\u3002\u5206\u65f6\u8c03\u5ea6\u6a21\u578b\u662f\u6307\u8ba9\u6240\u6709\u7684\u7ebf\u7a0b\u8f6e\u6d41\u83b7\u5f97 cpu \u7684\u4f7f\u7528\u6743,\u5e76\u4e14\u5e73\u5747\u5206\u914d\u6bcf\u4e2a\u7ebf\u7a0b\u5360\u7528\u7684 CPU \u7684\u65f6\u95f4\u7247\u8fd9\u4e2a\u4e5f\u6bd4\u8f83\u597d\u7406\u89e3\u3002Java\u865a\u62df\u673a\u91c7\u7528\u62a2\u5360\u5f0f\u8c03\u5ea6\u6a21\u578b\uff0c\u662f\u6307\u4f18\u5148\u8ba9\u53ef\u8fd0\u884c\u6c60\u4e2d\u4f18\u5148\u7ea7\u9ad8\u7684\u7ebf\u7a0b\u5360\u7528CPU\uff0c\u5982\u679c\u53ef\u8fd0\u884c\u6c60\u4e2d\u7684\u7ebf\u7a0b\u4f18\u5148\u7ea7\u76f8\u540c\uff0c\u90a3\u4e48\u5c31\u968f\u673a\u9009\u62e9\u4e00\u4e2a\u7ebf\u7a0b\uff0c\u4f7f\u5176\u5360\u7528CPU\u3002\u5904\u4e8e\u8fd0\u884c\u72b6\u6001\u7684\u7ebf\u7a0b\u4f1a\u4e00\u76f4\u8fd0\u884c\uff0c\u76f4\u81f3\u5b83\u4e0d\u5f97\u4e0d\u653e\u5f03 CPU\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">26\u3001\u4ec0\u4e48\u662f\u7ebf\u7a0b\u7ec4\uff0c\u4e3a\u4ec0\u4e48\u5728 Java \u4e2d\u4e0d\u63a8\u8350\u4f7f\u7528\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ebf\u7a0b\u7ec4\u548c\u7ebf\u7a0b\u6c60\u662f\u4e24\u4e2a\u4e0d\u540c\u7684\u6982\u5ff5\uff0c\u4ed6\u4eec\u7684\u4f5c\u7528\u5b8c\u5168\u4e0d\u540c\uff0c\u524d\u8005\u662f\u4e3a\u4e86\u65b9\u4fbf\u7ebf\u7a0b\u7684\u7ba1\u7406\uff0c\u540e\u8005\u662f\u4e3a\u4e86\u7ba1\u7406\u7ebf\u7a0b\u7684\u751f\u547d\u5468\u671f\uff0c\u590d\u7528\u7ebf\u7a0b\uff0c\u51cf\u5c11\u521b\u5efa\u9500\u6bc1\u7ebf\u7a0b\u7684\u5f00\u9500\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">27\u3001\u4e3a\u4ec0\u4e48\u4f7f\u7528 Executor \u6846\u67b6\u6bd4\u4f7f\u7528\u5e94\u7528\u521b\u5efa\u548c\u7ba1\u7406\u7ebf\u7a0b\u597d\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3a\u4ec0\u4e48\u8981\u4f7f\u7528 Executor \u7ebf\u7a0b\u6c60\u6846\u67b61\u3001\u6bcf\u6b21\u6267\u884c\u4efb\u52a1\u521b\u5efa\u7ebf\u7a0b new Thread()\u6bd4\u8f83\u6d88\u8017\u6027\u80fd\uff0c\u521b\u5efa\u4e00\u4e2a\u7ebf\u7a0b\u662f\u6bd4\u8f83\u8017\u65f6\u3001\u8017\u8d44\u6e90\u7684\u30022\u3001\u8c03\u7528 new Thread()\u521b\u5efa\u7684\u7ebf\u7a0b\u7f3a\u4e4f\u7ba1\u7406\uff0c\u88ab\u79f0\u4e3a\u91ce\u7ebf\u7a0b\uff0c\u800c\u4e14\u53ef\u4ee5\u65e0\u9650\u5236\u7684\u521b\u5efa\uff0c\u7ebf\u7a0b\u4e4b\u95f4\u7684\u76f8\u4e92\u7ade\u4e89\u4f1a\u5bfc\u81f4\u8fc7\u591a\u5360\u7528\u7cfb\u7edf\u8d44\u6e90\u800c\u5bfc\u81f4\u7cfb\u7edf\u762b\u75ea\uff0c\u8fd8\u6709\u7ebf\u7a0b\u4e4b\u95f4\u7684\u9891\u7e41\u4ea4\u66ff\u4e5f\u4f1a\u6d88\u8017\u5f88\u591a\u7cfb\u7edf\u8d44\u6e90\u30023\u3001\u76f4\u63a5\u4f7f\u7528 new Thread() \u542f\u52a8\u7684\u7ebf\u7a0b\u4e0d\u5229\u4e8e\u6269\u5c55\uff0c\u6bd4\u5982\u5b9a\u65f6\u6267\u884c\u3001\u5b9a\u671f\u6267\u884c\u3001\u5b9a\u65f6\u5b9a\u671f\u6267\u884c\u3001\u7ebf\u7a0b\u4e2d\u65ad\u7b49\u90fd\u4e0d\u4fbf\u5b9e\u73b0\u3002\u4f7f\u7528 Executor \u7ebf\u7a0b\u6c60\u6846\u67b6\u7684\u4f18\u70b9\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u80fd\u590d\u7528\u5df2\u5b58\u5728\u5e76\u7a7a\u95f2\u7684\u7ebf\u7a0b\u4ece\u800c\u51cf\u5c11\u7ebf\u7a0b\u5bf9\u8c61\u7684\u521b\u5efa\u4ece\u800c\u51cf\u5c11\u4e86\u6d88\u4ea1\u7ebf\u7a0b\u7684\u5f00\u9500\u3002<\/li><li>\u53ef\u6709\u6548\u63a7\u5236\u6700\u5927\u5e76\u53d1\u7ebf\u7a0b\u6570\uff0c\u63d0\u9ad8\u7cfb\u7edf\u8d44\u6e90\u4f7f\u7528\u7387\uff0c\u540c\u65f6\u907f\u514d\u8fc7\u591a\u8d44\u6e90\u7ade\u4e89\u3002<\/li><li>\u6846\u67b6\u4e2d\u5df2\u7ecf\u6709\u5b9a\u65f6\u3001\u5b9a\u671f\u3001\u5355\u7ebf\u7a0b\u3001\u5e76\u53d1\u6570\u63a7\u5236\u7b49\u529f\u80fd\u3002\u7efc\u4e0a\u6240\u8ff0\u4f7f\u7528\u7ebf\u7a0b\u6c60\u6846\u67b6 Executor \u80fd\u66f4\u597d\u7684\u7ba1\u7406\u7ebf\u7a0b\u3001\u63d0\u4f9b\u7cfb\u7edf\u8d44\u6e90\u4f7f\u7528\u7387\u3002<\/li><\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">28\u3001java \u4e2d\u6709\u51e0\u79cd\u65b9\u6cd5\u53ef\u4ee5\u5b9e\u73b0\u4e00\u4e2a\u7ebf\u7a0b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ee7\u627f Thread \u7c7b\u5b9e\u73b0 Runnable \u63a5\u53e3\u5b9e\u73b0 Callable \u63a5\u53e3\uff0c\u9700\u8981\u5b9e\u73b0\u7684\u662f call() \u65b9\u6cd5\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">29\u3001\u5982\u4f55\u505c\u6b62\u4e00\u4e2a\u6b63\u5728\u8fd0\u884c\u7684\u7ebf\u7a0b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528\u5171\u4eab\u53d8\u91cf\u7684\u65b9\u5f0f\u5728\u8fd9\u79cd\u65b9\u5f0f\u4e2d\uff0c\u4e4b\u6240\u4ee5\u5f15\u5165\u5171\u4eab\u53d8\u91cf\uff0c\u662f\u56e0\u4e3a\u8be5\u53d8\u91cf\u53ef\u4ee5\u88ab\u591a\u4e2a\u6267\u884c\u76f8\u540c\u4efb\u52a1\u7684\u7ebf\u7a0b\u7528\u6765\u4f5c\u4e3a\u662f\u5426\u4e2d\u65ad\u7684\u4fe1\u53f7\uff0c\u901a\u77e5\u4e2d\u65ad\u7ebf\u7a0b\u7684\u6267\u884c\u3002\u4f7f\u7528 interrupt \u65b9\u6cd5\u7ec8\u6b62\u7ebf\u7a0b\u5982\u679c\u4e00\u4e2a\u7ebf\u7a0b\u7531\u4e8e\u7b49\u5f85\u67d0\u4e9b\u4e8b\u4ef6\u7684\u53d1\u751f\u800c\u88ab\u963b\u585e\uff0c\u53c8\u8be5\u600e\u6837\u505c\u6b62\u8be5\u7ebf\u7a0b\u5462\uff1f\u8fd9\u79cd\u60c5\u51b5\u7ecf\u5e38\u4f1a\u53d1\u751f\uff0c\u6bd4\u5982\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u7531\u4e8e\u9700\u8981\u7b49\u5019\u952e\u76d8\u8f93\u5165\u800c\u88ab\u963b\u585e\uff0c\u6216\u8005\u8c03\u7528Thread.join()\u65b9\u6cd5\uff0c\u6216\u8005 Thread.sleep()\u65b9\u6cd5\uff0c\u5728\u7f51\u7edc\u4e2d\u8c03\u7528ServerSocket.accept()\u65b9\u6cd5\uff0c\u6216\u8005\u8c03\u7528\u4e86 DatagramSocket.receive()\u65b9\u6cd5\u65f6\uff0c\u90fd\u6709\u53ef\u80fd\u5bfc\u81f4\u7ebf\u7a0b\u963b\u585e\uff0c\u4f7f\u7ebf\u7a0b\u5904\u4e8e\u5904\u4e8e\u4e0d\u53ef\u8fd0\u884c\u72b6\u6001\u65f6\uff0c\u5373\u4f7f\u4e3b\u7a0b\u5e8f\u4e2d\u5c06\u8be5\u7ebf\u7a0b\u7684\u5171\u4eab\u53d8\u91cf\u8bbe\u7f6e\u4e3a true\uff0c\u4f46\u8be5\u7ebf\u7a0b\u6b64\u65f6\u6839\u672c\u65e0\u6cd5\u68c0\u67e5\u5faa\u73af\u6807\u5fd7\uff0c\u5f53\u7136\u4e5f\u5c31\u65e0\u6cd5\u7acb\u5373\u4e2d\u65ad\u3002\u8fd9\u91cc\u6211\u4eec\u7ed9\u51fa\u7684\u5efa\u8bae\u662f\uff0c\u4e0d\u8981\u4f7f\u7528 stop()\u65b9\u6cd5\uff0c\u800c\u662f\u4f7f\u7528 Thread \u63d0\u4f9b\u7684interrupt()\u65b9\u6cd5\uff0c\u56e0\u4e3a\u8be5\u65b9\u6cd5\u867d\u7136\u4e0d\u4f1a\u4e2d\u65ad\u4e00\u4e2a\u6b63\u5728\u8fd0\u884c\u7684\u7ebf\u7a0b\uff0c\u4f46\u662f\u5b83\u53ef\u4ee5\u4f7f\u4e00\u4e2a\u88ab\u963b\u585e\u7684\u7ebf\u7a0b\u629b\u51fa\u4e00\u4e2a\u4e2d\u65ad\u5f02\u5e38\uff0c\u4ece\u800c\u4f7f\u7ebf\u7a0b\u63d0\u524d\u7ed3\u675f\u963b\u585e\u72b6\u6001\uff0c\u9000\u51fa\u5835\u585e\u4ee3\u7801\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">30\u3001notify()\u548c notifyAll()\u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u8fdb\u5165 wait \u4e4b\u540e\uff0c\u5c31\u5fc5\u987b\u7b49\u5176\u4ed6\u7ebf\u7a0b notify\/notifyall,\u4f7f\u7528 notifyall,\u53ef\u4ee5\u5524\u9192\u6240\u6709\u5904\u4e8e wait \u72b6\u6001\u7684\u7ebf\u7a0b\uff0c\u4f7f\u5176\u91cd\u65b0\u8fdb\u5165\u9501\u7684\u4e89\u593a\u961f\u5217\u4e2d\uff0c\u800c notify \u53ea\u80fd\u5524\u9192\u4e00\u4e2a\u3002\u5982\u679c\u6ca1\u628a\u63e1\uff0c\u5efa\u8bae notifyAll\uff0c\u9632\u6b62 notigy \u56e0\u4e3a\u4fe1\u53f7\u4e22\u5931\u800c\u9020\u6210\u7a0b\u5e8f\u5f02\u5e38\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">31\u3001\u4ec0\u4e48\u662f Daemon \u7ebf\u7a0b\uff1f\u5b83\u6709\u4ec0\u4e48\u610f\u4e49\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6240\u8c13\u540e\u53f0(daemon)\u7ebf\u7a0b\uff0c\u662f\u6307\u5728\u7a0b\u5e8f\u8fd0\u884c\u7684\u65f6\u5019\u5728\u540e\u53f0\u63d0\u4f9b\u4e00\u79cd\u901a\u7528\u670d\u52a1\u7684\u7ebf\u7a0b\uff0c\u5e76\u4e14\u8fd9\u4e2a\u7ebf\u7a0b\u5e76\u4e0d\u5c5e\u4e8e\u7a0b\u5e8f\u4e2d\u4e0d\u53ef\u6216\u7f3a\u7684\u90e8\u5206\u3002\u56e0\u6b64\uff0c\u5f53\u6240\u6709\u7684\u975e\u540e\u53f0\u7ebf\u7a0b\u7ed3\u675f\u65f6\uff0c\u7a0b\u5e8f\u4e5f\u5c31\u7ec8\u6b62\u4e86\uff0c\u540c\u65f6\u4f1a\u6740\u6b7b\u8fdb\u7a0b\u4e2d\u7684\u6240\u6709\u540e\u53f0\u7ebf\u7a0b\u3002\u53cd\u8fc7\u6765\u8bf4\uff0c\u53ea\u8981\u6709\u4efb\u4f55\u975e\u540e\u53f0\u7ebf\u7a0b\u8fd8\u5728\u8fd0\u884c\uff0c\u7a0b\u5e8f\u5c31\u4e0d\u4f1a\u7ec8\u6b62\u3002\u5fc5\u987b\u5728\u7ebf\u7a0b\u542f\u52a8\u4e4b\u524d\u8c03\u7528setDaemon()\u65b9\u6cd5\uff0c\u624d\u80fd\u628a\u5b83\u8bbe\u7f6e\u4e3a\u540e\u53f0\u7ebf\u7a0b\u3002\u6ce8\u610f\uff1a\u540e\u53f0\u8fdb\u7a0b\u5728\u4e0d\u6267\u884c finally\u5b50\u53e5\u7684\u60c5\u51b5\u4e0b\u5c31\u4f1a\u7ec8\u6b62\u5176 run()\u65b9\u6cd5\u3002\u6bd4\u5982\uff1aJVM \u7684\u5783\u573e\u56de\u6536\u7ebf\u7a0b\u5c31\u662f Daemon \u7ebf\u7a0b\uff0cFinalizer \u4e5f\u662f\u5b88\u62a4\u7ebf\u7a0b\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">32\u3001\u7b80\u8ff0\u5806\u7684\u5e74\u8f7b\u4ee3\u548c\u8001\u5e74\u4ee3\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5806\u7684\u5e74\u8f7b\u4ee3\u5927\u5219\u8001\u5e74\u4ee3\u5c0f\uff0cGC\u5c11\uff0c\u4f46\u662f\u6bcf\u6b21\u65f6\u95f4\u4f1a\u6bd4\u8f83\u957f\u3002\u5e74\u8f7b\u4ee3\u5c0f\u5219\u8001\u5e74\u4ee3\u5927\uff0c\u4f1a\u7f29\u77ed\u6bcf\u6b21GC\u7684\u65f6\u95f4\uff0c\u4f46\u662f\u6b21\u6570\u9891\u7e41\u3002\u53ef\u4ee5\u8ba9\u8001\u5e74\u4ee3\u5c3d\u91cf\u7f13\u5b58\u5e38\u7528\u5bf9\u8c61\uff0cJVM\u9ed8\u8ba4\u5e74\u8f7b\u4ee3\u548c\u8001\u5e74\u4ee3\u7684\u5927\u5c0f\u6bd4\u4f8b\u4e3a1:2,\u3002\u89c2\u5bdf\u5cf0\u503c\u8001\u5e74\u4ee3\u5185\u5b58\uff0c\u4e0d\u5f71\u54cdfull GC\uff0c\u52a0\u5927\u8001\u5e74\u4ee3\u53ef\u8c031:1\uff0c\u4f46\u662f\u8981\u7ed9\u8001\u5e74\u4ee3\u9884\u7559\u4e09\u5206\u4e4b\u4e00\u7684\u7a7a\u95f4\u3002\u51cf\u5c11\u4f7f\u7528\u5168\u5c40\u53d8\u91cf\u548c\u5927\u5bf9\u8c61 \uff0c\u8c03\u6574\u65b0\u751f\u4ee3\uff0c\u8001\u5e74\u4ee3\u5230\u6700\u5408\u9002\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">33\u3001\u4ec0\u4e48\u662f\u53ef\u91cd\u5165\u9501\uff08ReentrantLock\uff09\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3e\u4f8b\u6765\u8bf4\u660e\u9501\u7684\u53ef\u91cd\u5165\u6027\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public class UnReentrant{\n\tLock lock = new Lock();\n\tpublic void outer(){\n\t\tlock.lock();\n\t\tinner();\n\t\tlock.unlock();\n\t}\n\tpublic void inner(){\n\t\tlock.lock();\n\t\t\/\/do something\n\t\tlock.unlock();\n\t}\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">outer \u4e2d\u8c03\u7528\u4e86 inner\uff0couter \u5148\u9501\u4f4f\u4e86 lock\uff0c\u8fd9\u6837 inner \u5c31\u4e0d\u80fd\u518d\u83b7\u53d6 lock\u3002\u5176\u5b9e\u8c03\u7528 outer \u7684\u7ebf\u7a0b\u5df2\u7ecf\u83b7\u53d6\u4e86 lock \u9501\uff0c\u4f46\u662f\u4e0d\u80fd\u5728 inner \u4e2d\u91cd\u590d\u5229\u7528\u5df2\u7ecf\u83b7\u53d6\u7684\u9501\u8d44\u6e90\uff0c\u8fd9\u79cd\u9501\u5373\u79f0\u4e4b\u4e3a \u4e0d\u53ef\u91cd\u5165\u53ef\u91cd\u5165\u5c31\u610f\u5473\u7740\uff1a\u7ebf\u7a0b\u53ef\u4ee5\u8fdb\u5165\u4efb\u4f55\u4e00\u4e2a\u5b83\u5df2\u7ecf\u62e5\u6709\u7684\u9501\u6240\u540c\u6b65\u7740\u7684\u4ee3\u7801\u5757\u3002synchronized\u3001ReentrantLock \u90fd\u662f\u53ef\u91cd\u5165\u7684\u9501\uff0c\u53ef\u91cd\u5165\u9501\u76f8\u5bf9\u6765\u8bf4\u7b80\u5316\u4e86\u5e76\u53d1\u7f16\u7a0b\u7684\u5f00\u53d1\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">34\u3001\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u8fdb\u5165\u67d0\u4e2a\u5bf9\u8c61\u7684\u4e00\u4e2a synchronized \u7684\u5b9e\u4f8b\u65b9\u6cd5\u540e\uff0c\u5176\u5b83\u7ebf\u7a0b\u662f\u5426\u53ef\u8fdb\u5165\u6b64\u5bf9\u8c61\u7684\u5176\u5b83\u65b9\u6cd5\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u5176\u4ed6\u65b9\u6cd5\u6ca1\u6709 synchronized \u7684\u8bdd\uff0c\u5176\u4ed6\u7ebf\u7a0b\u662f\u53ef\u4ee5\u8fdb\u5165\u7684\u3002\u6240\u4ee5\u8981\u5f00\u653e\u4e00\u4e2a\u7ebf\u7a0b\u5b89\u5168\u7684\u5bf9\u8c61\u65f6\uff0c\u5f97\u4fdd\u8bc1\u6bcf\u4e2a\u65b9\u6cd5\u90fd\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">35\u3001\u4e50\u89c2\u9501\u548c\u60b2\u89c2\u9501\u7684\u7406\u89e3\u53ca\u5982\u4f55\u5b9e\u73b0\uff0c\u6709\u54ea\u4e9b\u5b9e\u73b0\u65b9\u5f0f\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u60b2\u89c2\u9501\uff1a\u603b\u662f\u5047\u8bbe\u6700\u574f\u7684\u60c5\u51b5\uff0c\u6bcf\u6b21\u53bb\u62ff\u6570\u636e\u7684\u65f6\u5019\u90fd\u8ba4\u4e3a\u522b\u4eba\u4f1a\u4fee\u6539\uff0c\u6240\u4ee5\u6bcf\u6b21\u5728\u62ff\u6570\u636e\u7684\u65f6\u5019\u90fd\u4f1a\u4e0a\u9501\uff0c\u8fd9\u6837\u522b\u4eba\u60f3\u62ff\u8fd9\u4e2a\u6570\u636e\u5c31\u4f1a\u963b\u585e\u76f4\u5230\u5b83\u62ff\u5230\u9501\u3002\u4f20\u7edf\u7684\u5173\u7cfb\u578b\u6570\u636e\u5e93\u91cc\u8fb9\u5c31\u7528\u5230\u4e86\u5f88\u591a\u8fd9\u79cd\u9501\u673a\u5236\uff0c\u6bd4\u5982\u884c\u9501\uff0c\u8868\u9501\u7b49\uff0c\u8bfb\u9501\uff0c\u5199\u9501\u7b49\uff0c\u90fd\u662f\u5728\u505a\u64cd\u4f5c\u4e4b\u524d\u5148\u4e0a\u9501\u3002\u518d\u6bd4\u5982 Java \u91cc\u9762\u7684\u540c\u6b65\u539f\u8bed synchronized \u5173\u952e\u5b57\u7684\u5b9e\u73b0\u4e5f\u662f\u60b2\u89c2\u9501\u3002\u4e50\u89c2\u9501\uff1a\u987e\u540d\u601d\u4e49\uff0c\u5c31\u662f\u5f88\u4e50\u89c2\uff0c\u6bcf\u6b21\u53bb\u62ff\u6570\u636e\u7684\u65f6\u5019\u90fd\u8ba4\u4e3a\u522b\u4eba\u4e0d\u4f1a\u4fee\u6539\uff0c\u6240\u4ee5\u4e0d\u4f1a\u4e0a\u9501\uff0c\u4f46\u662f\u5728\u66f4\u65b0\u7684\u65f6\u5019\u4f1a\u5224\u65ad\u4e00\u4e0b\u5728\u6b64\u671f\u95f4\u522b\u4eba\u6709\u6ca1\u6709\u53bb\u66f4\u65b0\u8fd9\u4e2a\u6570\u636e\uff0c\u53ef\u4ee5\u4f7f\u7528\u7248\u672c\u53f7\u7b49\u673a\u5236\u3002\u4e50\u89c2\u9501\u9002\u7528\u4e8e\u591a\u8bfb\u7684\u5e94\u7528\u7c7b\u578b\uff0c\u8fd9\u6837\u53ef\u4ee5\u63d0\u9ad8\u541e\u5410\u91cf\uff0c\u50cf\u6570\u636e\u5e93\u63d0\u4f9b\u7684\u7c7b\u4f3c\u4e8e write_condition \u673a\u5236\uff0c\u5176\u5b9e\u90fd\u662f\u63d0\u4f9b\u7684\u4e50\u89c2\u9501\u3002\u5728 Java\u4e2d java.util.concurrent.atomic \u5305\u4e0b\u9762\u7684\u539f\u5b50\u53d8\u91cf\u7c7b\u5c31\u662f\u4f7f\u7528\u4e86\u4e50\u89c2\u9501\u7684\u4e00\u79cd\u5b9e\u73b0\u65b9\u5f0f CAS \u5b9e\u73b0\u7684\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e50\u89c2\u9501\u7684\u5b9e\u73b0\u65b9\u5f0f\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u4f7f\u7528\u7248\u672c\u6807\u8bc6\u6765\u786e\u5b9a\u8bfb\u5230\u7684\u6570\u636e\u4e0e\u63d0\u4ea4\u65f6\u7684\u6570\u636e\u662f\u5426\u4e00\u81f4\u3002\u63d0\u4ea4\u540e\u4fee\u6539\u7248\u672c\u6807\u8bc6\uff0c\u4e0d\u4e00\u81f4\u65f6\u53ef\u4ee5\u91c7\u53d6\u4e22\u5f03\u548c\u518d\u6b21\u5c1d\u8bd5\u7684\u7b56\u7565\u3002<\/li><li>java \u4e2d\u7684 Compare and Swap \u5373 CAS \uff0c\u5f53\u591a\u4e2a\u7ebf\u7a0b\u5c1d\u8bd5\u4f7f\u7528 CAS \u540c\u65f6\u66f4\u65b0\u540c\u4e00\u4e2a\u53d8\u91cf\u65f6\uff0c\u53ea\u6709\u5176\u4e2d\u4e00\u4e2a\u7ebf\u7a0b\u80fd\u66f4\u65b0\u53d8\u91cf\u7684\u503c\uff0c\u800c\u5176\u5b83\u7ebf\u7a0b\u90fd\u5931\u8d25\uff0c\u5931\u8d25\u7684\u7ebf\u7a0b\u5e76\u4e0d\u4f1a\u88ab\u6302\u8d77\uff0c\u800c\u662f\u88ab\u544a\u77e5\u8fd9\u6b21\u7ade\u4e89\u4e2d\u5931\u8d25\uff0c\u5e76\u53ef\u4ee5\u518d\u6b21\u5c1d\u8bd5\u3002 CAS \u64cd\u4f5c\u4e2d\u5305\u542b\u4e09\u4e2a\u64cd\u4f5c\u6570 \u2014\u2014 \u9700\u8981\u8bfb\u5199\u7684\u5185\u5b58\u4f4d\u7f6e\uff08V\uff09\u3001\u8fdb\u884c\u6bd4\u8f83\u7684\u9884\u671f\u539f\u503c\uff08A\uff09\u548c\u62df\u5199\u5165\u7684\u65b0\u503c(B)\u3002\u5982\u679c\u5185\u5b58\u4f4d\u7f6e V \u7684\u503c\u4e0e\u9884\u671f\u539f\u503c A \u76f8\u5339\u914d\uff0c\u90a3\u4e48\u5904\u7406\u5668\u4f1a\u81ea\u52a8\u5c06\u8be5\u4f4d\u7f6e\u503c\u66f4\u65b0\u4e3a\u65b0\u503c B\u3002\u5426\u5219\u5904\u7406\u5668\u4e0d\u505a\u4efb\u4f55\u64cd\u4f5c\u3002<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">CAS \u7f3a\u70b9\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>ABA \u95ee\u9898\uff1a\u6bd4\u5982\u8bf4\u4e00\u4e2a\u7ebf\u7a0b one \u4ece\u5185\u5b58\u4f4d\u7f6e V \u4e2d\u53d6\u51fa A\uff0c\u8fd9\u65f6\u5019\u53e6\u4e00\u4e2a\u7ebf\u7a0b two \u4e5f\u4ece\u5185\u5b58\u4e2d\u53d6\u51fa A\uff0c\u5e76\u4e14 two \u8fdb\u884c\u4e86\u4e00\u4e9b\u64cd\u4f5c\u53d8\u6210\u4e86 B\uff0c\u7136\u540e two \u53c8\u5c06 V \u4f4d\u7f6e\u7684\u6570\u636e\u53d8\u6210 A\uff0c\u8fd9\u65f6\u5019\u7ebf\u7a0b one \u8fdb\u884c CAS \u64cd\u4f5c\u53d1\u73b0\u5185\u5b58\u4e2d\u4ecd\u7136\u662f A\uff0c\u7136\u540e one \u64cd\u4f5c\u6210\u529f\u3002\u5c3d\u7ba1\u7ebf\u7a0b one \u7684 CAS \u64cd\u4f5c\u6210\u529f\uff0c\u4f46\u53ef\u80fd\u5b58\u5728\u6f5c\u85cf\u7684\u95ee\u9898\u3002\u4ece Java1.5 \u5f00\u59cb JDK \u7684 atomic\u5305\u91cc\u63d0\u4f9b\u4e86\u4e00\u4e2a\u7c7b AtomicStampedReference \u6765\u89e3\u51b3 ABA \u95ee\u9898\u3002<\/li><li>\u5faa\u73af\u65f6\u95f4\u957f\u5f00\u9500\u5927\uff1a\u5bf9\u4e8e\u8d44\u6e90\u7ade\u4e89\u4e25\u91cd\uff08\u7ebf\u7a0b\u51b2\u7a81\u4e25\u91cd\uff09\u7684\u60c5\u51b5\uff0cCAS \u81ea\u65cb\u7684\u6982\u7387\u4f1a\u6bd4\u8f83\u5927\uff0c\u4ece\u800c\u6d6a\u8d39\u66f4\u591a\u7684 CPU \u8d44\u6e90\uff0c\u6548\u7387\u4f4e\u4e8e synchronized\u3002<\/li><li>\u53ea\u80fd\u4fdd\u8bc1\u4e00\u4e2a\u5171\u4eab\u53d8\u91cf\u7684\u539f\u5b50\u64cd\u4f5c\uff1a\u5f53\u5bf9\u4e00\u4e2a\u5171\u4eab\u53d8\u91cf\u6267\u884c\u64cd\u4f5c\u65f6\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u5faa\u73af CAS \u7684\u65b9\u5f0f\u6765\u4fdd\u8bc1\u539f\u5b50\u64cd\u4f5c\uff0c\u4f46\u662f\u5bf9\u591a\u4e2a\u5171\u4eab\u53d8\u91cf\u64cd\u4f5c\u65f6\uff0c\u5faa\u73af CAS \u5c31\u65e0\u6cd5\u4fdd\u8bc1\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff0c\u8fd9\u4e2a\u65f6\u5019\u5c31\u53ef\u4ee5\u7528\u9501\u3002<\/li><\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">36\u3001SynchronizedMap \u548c ConcurrentHashMap \u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SynchronizedMap \u4e00\u6b21\u9501\u4f4f\u6574\u5f20\u8868\u6765\u4fdd\u8bc1\u7ebf\u7a0b\u5b89\u5168\uff0c\u6240\u4ee5\u6bcf\u6b21\u53ea\u80fd\u6709\u4e00\u4e2a\u7ebf\u7a0b\u6765\u8bbf\u4e3a map\u3002ConcurrentHashMap \u4f7f\u7528\u5206\u6bb5\u9501\u6765\u4fdd\u8bc1\u5728\u591a\u7ebf\u7a0b\u4e0b\u7684\u6027\u80fd\u3002ConcurrentHashMap \u4e2d\u5219\u662f\u4e00\u6b21\u9501\u4f4f\u4e00\u4e2a\u6876\u3002ConcurrentHashMap \u9ed8\u8ba4\u5c06hash \u8868\u5206\u4e3a 16 \u4e2a\u6876\uff0c\u8bf8\u5982 get,put,remove \u7b49\u5e38\u7528\u64cd\u4f5c\u53ea\u9501\u5f53\u524d\u9700\u8981\u7528\u5230\u7684\u6876\u3002\u8fd9\u6837\uff0c\u539f\u6765\u53ea\u80fd\u4e00\u4e2a\u7ebf\u7a0b\u8fdb\u5165\uff0c\u73b0\u5728\u5374\u80fd\u540c\u65f6\u6709 16 \u4e2a\u5199\u7ebf\u7a0b\u6267\u884c\uff0c\u5e76\u53d1\u6027\u80fd\u7684\u63d0\u5347\u662f\u663e\u800c\u6613\u89c1\u7684\u3002\u53e6\u5916 ConcurrentHashMap \u4f7f\u7528\u4e86\u4e00\u79cd\u4e0d\u540c\u7684\u8fed\u4ee3\u65b9\u5f0f\u3002\u5728\u8fd9\u79cd\u8fed\u4ee3\u65b9\u5f0f\u4e2d\uff0c\u5f53iterator \u88ab\u521b\u5efa\u540e\u96c6\u5408\u518d\u53d1\u751f\u6539\u53d8\u5c31\u4e0d\u518d\u662f\u629b\u51faConcurrentModificationException\uff0c\u53d6\u800c\u4ee3\u4e4b\u7684\u662f\u5728\u6539\u53d8\u65f6 new \u65b0\u7684\u6570\u636e\u4ece\u800c\u4e0d\u5f71\u54cd\u539f\u6709\u7684\u6570\u636e \uff0citerator \u5b8c\u6210\u540e\u518d\u5c06\u5934\u6307\u9488\u66ff\u6362\u4e3a\u65b0\u7684\u6570\u636e \uff0c\u8fd9\u6837 iterator\u7ebf\u7a0b\u53ef\u4ee5\u4f7f\u7528\u539f\u6765\u8001\u7684\u6570\u636e\uff0c\u800c\u5199\u7ebf\u7a0b\u4e5f\u53ef\u4ee5\u5e76\u53d1\u7684\u5b8c\u6210\u6539\u53d8\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">37\u3001CopyOnWriteArrayList \u53ef\u4ee5\u7528\u4e8e\u4ec0\u4e48\u5e94\u7528\u573a\u666f\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">CopyOnWriteArrayList(\u514d\u9501\u5bb9\u5668)\u7684\u597d\u5904\u4e4b\u4e00\u662f\u5f53\u591a\u4e2a\u8fed\u4ee3\u5668\u540c\u65f6\u904d\u5386\u548c\u4fee\u6539\u8fd9\u4e2a\u5217\u8868\u65f6\uff0c\u4e0d\u4f1a\u629b\u51fa ConcurrentModificationException\u3002\u5728CopyOnWriteArrayList \u4e2d\uff0c\u5199\u5165\u5c06\u5bfc\u81f4\u521b\u5efa\u6574\u4e2a\u5e95\u5c42\u6570\u7ec4\u7684\u526f\u672c\uff0c\u800c\u6e90\u6570\u7ec4\u5c06\u4fdd\u7559\u5728\u539f\u5730\uff0c\u4f7f\u5f97\u590d\u5236\u7684\u6570\u7ec4\u5728\u88ab\u4fee\u6539\u65f6\uff0c\u8bfb\u53d6\u64cd\u4f5c\u53ef\u4ee5\u5b89\u5168\u5730\u6267\u884c\u30021\u3001\u7531\u4e8e\u5199\u64cd\u4f5c\u7684\u65f6\u5019\uff0c\u9700\u8981\u62f7\u8d1d\u6570\u7ec4\uff0c\u4f1a\u6d88\u8017\u5185\u5b58\uff0c\u5982\u679c\u539f\u6570\u7ec4\u7684\u5185\u5bb9\u6bd4\u8f83\u591a\u7684\u60c5\u51b5\u4e0b\uff0c\u53ef\u80fd\u5bfc\u81f4 young gc \u6216\u8005 full gc\uff1b2\u3001\u4e0d\u80fd\u7528\u4e8e\u5b9e\u65f6\u8bfb\u7684\u573a\u666f\uff0c\u50cf\u62f7\u8d1d\u6570\u7ec4\u3001\u65b0\u589e\u5143\u7d20\u90fd\u9700\u8981\u65f6\u95f4\uff0c\u6240\u4ee5\u8c03\u7528\u4e00\u4e2a set\u64cd\u4f5c\u540e\uff0c\u8bfb\u53d6\u5230\u6570\u636e\u53ef\u80fd\u8fd8\u662f\u65e7\u7684,\u867d\u7136 CopyOnWriteArrayList \u80fd\u505a\u5230\u6700\u7ec8\u4e00\u81f4\u6027,\u4f46\u662f\u8fd8\u662f\u6ca1\u6cd5\u6ee1\u8db3\u5b9e\u65f6\u6027\u8981\u6c42\uff1bCopyOnWriteArrayList \u900f\u9732\u7684\u601d\u60f31\u3001\u8bfb\u5199\u5206\u79bb\uff0c\u8bfb\u548c\u5199\u5206\u5f002\u3001\u6700\u7ec8\u4e00\u81f4\u60273\u3001\u4f7f\u7528\u53e6\u5916\u5f00\u8f9f\u7a7a\u95f4\u7684\u601d\u8def\uff0c\u6765\u89e3\u51b3\u5e76\u53d1\u51b2\u7a81\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">38\u3001\u4ec0\u4e48\u53eb\u7ebf\u7a0b\u5b89\u5168\uff1fservlet \u662f\u7ebf\u7a0b\u5b89\u5168\u5417?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ebf\u7a0b\u5b89\u5168\u662f\u7f16\u7a0b\u4e2d\u7684\u672f\u8bed\uff0c\u6307\u67d0\u4e2a\u51fd\u6570\u3001\u51fd\u6570\u5e93\u5728\u591a\u7ebf\u7a0b\u73af\u5883\u4e2d\u88ab\u8c03\u7528\u65f6\uff0c\u80fd\u591f\u6b63\u786e\u5730\u5904\u7406\u591a\u4e2a\u7ebf\u7a0b\u4e4b\u95f4\u7684\u5171\u4eab\u53d8\u91cf\uff0c\u4f7f\u7a0b\u5e8f\u529f\u80fd\u6b63\u786e\u5b8c\u6210\u3002Servlet \u4e0d\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff0cservlet \u662f\u5355\u5b9e\u4f8b\u591a\u7ebf\u7a0b\u7684\uff0c\u5f53\u591a\u4e2a\u7ebf\u7a0b\u540c\u65f6\u8bbf\u95ee\u540c\u4e00\u4e2a\u65b9\u6cd5\uff0c\u662f\u4e0d\u80fd\u4fdd\u8bc1\u5171\u4eab\u53d8\u91cf\u7684\u7ebf\u7a0b\u5b89\u5168\u6027\u7684\u3002Struts2 \u7684 action \u662f\u591a\u5b9e\u4f8b\u591a\u7ebf\u7a0b\u7684\uff0c\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff0c\u6bcf\u4e2a\u8bf7\u6c42\u8fc7\u6765\u90fd\u4f1a new \u4e00\u4e2a\u65b0\u7684 action \u5206\u914d\u7ed9\u8fd9\u4e2a\u8bf7\u6c42\uff0c\u8bf7\u6c42\u5b8c\u6210\u540e\u9500\u6bc1\u3002SpringMVC \u7684 Controller \u662f\u7ebf\u7a0b\u5b89\u5168\u7684\u5417\uff1f\u4e0d\u662f\u7684\uff0c\u548c Servlet \u7c7b\u4f3c\u7684\u5904\u7406\u6d41\u7a0b\u3002Struts2 \u597d\u5904\u662f\u4e0d\u7528\u8003\u8651\u7ebf\u7a0b\u5b89\u5168\u95ee\u9898\uff1bServlet \u548c SpringMVC \u9700\u8981\u8003\u8651\u7ebf\u7a0b\u5b89\u5168\u95ee\u9898\uff0c\u4f46\u662f\u6027\u80fd\u53ef\u4ee5\u63d0\u5347\u4e0d\u7528\u5904\u7406\u592a\u591a\u7684 gc\uff0c\u53ef\u4ee5\u4f7f\u7528 ThreadLocal \u6765\u5904\u7406\u591a\u7ebf\u7a0b\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">39\u3001volatile \u6709\u4ec0\u4e48\u7528\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u80fd\u5426\u7528\u4e00\u53e5\u8bdd\u8bf4\u660e\u4e0b volatile \u7684\u5e94\u7528\u573a\u666f\uff1fvolatile \u4fdd\u8bc1\u5185\u5b58\u53ef\u89c1\u6027\u548c\u7981\u6b62\u6307\u4ee4\u91cd\u6392\u3002volatile \u7528\u4e8e\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\u7684\u5355\u6b21\u64cd\u4f5c(\u5355\u6b21\u8bfb\u6216\u8005\u5355\u6b21\u5199)\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">40\u3001\u4e3a\u4ec0\u4e48\u4ee3\u7801\u4f1a\u91cd\u6392\u5e8f\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u6267\u884c\u7a0b\u5e8f\u65f6\uff0c\u4e3a\u4e86\u63d0\u4f9b\u6027\u80fd\uff0c\u5904\u7406\u5668\u548c\u7f16\u8bd1\u5668\u5e38\u5e38\u4f1a\u5bf9\u6307\u4ee4\u8fdb\u884c\u91cd\u6392\u5e8f\uff0c\u4f46\u662f\u4e0d\u80fd\u968f\u610f\u91cd\u6392\u5e8f\uff0c\u4e0d\u662f\u4f60\u60f3\u600e\u4e48\u6392\u5e8f\u5c31\u600e\u4e48\u6392\u5e8f\uff0c\u5b83\u9700\u8981\u6ee1\u8db3\u4ee5\u4e0b\u4e24\u4e2a\u6761\u4ef6\uff1a\u5728\u5355\u7ebf\u7a0b\u73af\u5883\u4e0b\u4e0d\u80fd\u6539\u53d8\u7a0b\u5e8f\u8fd0\u884c\u7684\u7ed3\u679c\uff1b\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\u7684\u4e0d\u5141\u8bb8\u91cd\u6392\u5e8f\u9700\u8981\u6ce8\u610f\u7684\u662f\uff1a\u91cd\u6392\u5e8f\u4e0d\u4f1a\u5f71\u54cd\u5355\u7ebf\u7a0b\u73af\u5883\u7684\u6267\u884c\u7ed3\u679c\uff0c\u4f46\u662f\u4f1a\u7834\u574f\u591a\u7ebf\u7a0b\u7684\u6267\u884c\u8bed\u4e49\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">41\u3001\u5728 java \u4e2d wait \u548c sleep \u65b9\u6cd5\u7684\u4e0d\u540c\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u5927\u7684\u4e0d\u540c\u662f\u5728\u7b49\u5f85\u65f6 wait \u4f1a\u91ca\u653e\u9501\uff0c\u800c sleep \u4e00\u76f4\u6301\u6709\u9501\u3002Wait \u901a\u5e38\u88ab\u7528\u4e8e\u7ebf\u7a0b\u95f4\u4ea4\u4e92\uff0csleep \u901a\u5e38\u88ab\u7528\u4e8e\u6682\u505c\u6267\u884c\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">42\u3001\u7528 Java \u5b9e\u73b0\u963b\u585e\u961f\u5217<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import java.util.LinkedList;\nimport java.util.concurrent.atomic.AtomicInteger;\n\n\/**\n * \u4f7f\u7528wait\u548cnotify\u5b9e\u73b0Queue\n * BlockingQueue: \u987e\u540d\u601d\u4e49\uff0c\u9996\u5148\u5b83\u662f\u4e00\u4e2a\u961f\u5217\uff0c\u5e76\u4e14\u652f\u6301\u963b\u585e\u673a\u5236\uff0c\u963b\u585e\u7684\u653e\u5165\u548c\u963b\u585e\u7684\u5f97\u5230\u6570\u636e\uff0c\n * \u6211\u4eec\u8981\u5b9e\u73b0LinkedBlockingQueue\u4e0b\u9762\u4e0b\u9762\u4e24\u4e2a\u7b80\u5355\u7684\u65b9\u6cd5put\u548ctake\n * put(anObject):\u628a\u628a\u5bf9\u8c61\u52a0\u5230BlockingQueue\u91cc\u9762\uff0c\u5982\u679cBlockQueue\u6ca1\u6709\u7a7a\u95f4\uff0c\u5219\u8c03\u7528\u6b64\u65b9\u6cd5\u7684\u7ebf\u7a0b\u88ab\u963b\u65ad\n * \u76f4\u5230BlockingQueue\u91cc\u9762\u6ca1\u6709\u7a7a\u95f4\u5728\u7ee7\u7eed\u3002\n *take():\u53d6\u8d70blockingQueue\u91cc\u9762\u8be5\u5728\u9996\u4f4d\u7684\u5bf9\u8c61\uff0c\u82e5blockingQueue\u4e3a\u7a7a\uff0c\u963b\u585e\u8fdb\u5165\u7b49\u5f85\u72b6\u6001\uff0c\u76f4\u5230BlockingQueue\u6709\u65b0\u7684\u6570\u636e\u88ab\u52a0\u5165\n * \n * wait \u548cnotify \u7ed3\u5408synchronized\u4f7f\u7528\n * \n *  *\/\npublic class MyQueue {\n\n    \/\/1.\u9700\u8981\u88c5\u5143\u7d20\u7684\u96c6\u5408\n    private final LinkedList&lt;Object&gt; list = new LinkedList&lt;Object&gt;();\n\n    \/**\n     * 2.\u9700\u8981\u4e00\u4e2a\u8ba1\u6570\u5668\uff0c\u7edf\u8ba1\u52a0\u5165list\u51e0\u4e2a\u7684\u4e2a\u6570\n     *AtomicInteger\uff0c\u4e00\u4e2a\u63d0\u4f9b\u539f\u5b50\u64cd\u4f5c\u7684Integer\u7684\u7c7b\u3002\u5728Java\u8bed\u8a00\u4e2d\n     *\uff0c++i\u548ci++\u64cd\u4f5c\u5e76\u4e0d\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff0c\u5728\u4f7f\u7528\u7684\u65f6\u5019\uff0c\u4e0d\u53ef\u907f\u514d\u7684\u4f1a\u7528\u5230\n     *synchronized\u5173\u952e\u5b57\u3002\u800cAtomicInteger\u5219\u901a\u8fc7\u4e00\u79cd\u7ebf\u7a0b\u5b89\u5168\u7684\u52a0\u51cf\u64cd\u4f5c\u63a5\u53e3\u3002\n     * *\/\n    private AtomicInteger count = new AtomicInteger(0);\n\n    \/\/\u6307\u5b9a\u4e0a\u9650\u4e0a\u9650\u548c\u4e0b\u9650\n    private final int minSize = 0;\n    private final int maxSize;\n    \/\/\u6784\u9020\u65b9\u6cd5\uff0c\u6784\u9020\u5bb9\u5668\u6700\u5927\u957f\u5ea6\n    public MyQueue(int size) {\n        this.maxSize = size;\n    }\n    public MyQueue() {\n        \/\/\u6700\u5927\u957f\u5ea6\u9ed8\u8ba4\u4e3a10\n        this(10);\n    }\n\n    \/**\n     * \u521d\u59cb\u5316\u4e00\u4e2a\u5bf9\u8c61\u7528\u4e8e\u52a0\u9501\n     * *\/\n    private final Object lock = new Object();\n\n\n    \/\/\u8fd4\u56de\u957f\u5ea6\n    public int size() {\n        return count.get();\n    }\n\n\n    \/**\n     * \u6dfb\u52a0\u4e00\u4e2a\u5bf9\u8c61\uff0c\u5982\u679c\u961f\u5217\u6ee1\u4e86\uff0c\u5219\u963b\u585e\n     * *\/\n    public void put(Object obj) {\n        synchronized (lock) {\n            \/\/\u5982\u679c\u5bb9\u5668\u5927\u5c0f\u521a\u597d\u7b49\u4e8e\u6700\u5927\u957f\u5ea6\uff0c\u5219\u963b\u585e\n            while(size() == maxSize) {\n                try {\n                    lock.wait();\/\/\u963b\u585e\n                } catch (InterruptedException e) {\n                    \/\/ TODO Auto-generated catch block\n                    e.printStackTrace();\n                }\n            }\n            list.add(obj);\n            count.incrementAndGet();\/\/\u76f8\u5f53\u4e8ei++\n            System.out.println(\"\u65b0\u52a0\u5165\u7684\u5143\u7d20\u4e3a\uff1a\"+obj);\n            lock.notify();\/\/\u901a\u77e5\u53e6\u5916\u4e00\u4e2a\u7ebf\u7a0b\u53bb\u53d6\u5143\u7d20\n        }\n    }\n    \/**\n     * \u53d6\u51fa\u4e00\u4e2a\u5143\u7d20\uff0c\u5982\u679c\u961f\u5217\u4e3a\u7a7a\uff0c\u5219\u963b\u585e\n     * *\/\n    public Object take() {\n        synchronized (lock) {\n        \/\/\u5982\u679c\u5bb9\u5668\u7684\u5927\u5c0f\u521a\u597d\u7b49\u4e8e\u961f\u5217\u6700\u5c0f\u957f\u5ea6\uff0c\u5219\u963b\u585e\n            while(minSize == size()) {\n                try {\n                lock.wait();\n                } catch (InterruptedException e) {\n                \/\/ TODO Auto-generated catch block\n                e.printStackTrace();\n                }\n            }\n            \/\/\u53d6\u51fa\u7b2c\u4e00\u4e2a\u5143\u7d20\n            Object obj = list.removeFirst();\n            \/\/\u8ba1\u6570\u5668\u9012\u51cf\n            count.decrementAndGet();\n            lock.notify();\/\/\u901a\u77e5\u53e6\u5916\u4e00\u4e2a\u7ebf\u7a0b\u8fdb\u884c\u6dfb\u52a0\u5143\u7d20\n            return obj;\/\/\u8fd4\u56de\u7ed3\u679c\n\n        }\n    }\n    public static void main(String[] args) {\n        final MyQueue m = new MyQueue(5);\n\n        Thread t1 = new Thread(new Runnable() {\n\n            @Override\n            public void run() {\n                m.put(\"a\");\n                m.put(\"b\");\n                m.put(\"c\");\n                m.put(\"d\");\n                m.put(\"e\");\n                m.put(\"f\");\n\n            }\n        });\n        t1.start();\n\n        try {\n            Thread.sleep(1000);\n            System.out.println(\"\u5f53\u524d\u5bb9\u5668\u7684\u5927\u5c0f\uff1a\"+m.size());\n        } catch (InterruptedException e) {\n            \/\/ TODO Auto-generated catch block\n            e.printStackTrace();\n        }\n        Thread t2 = new Thread(new Runnable() {\n\n                    @Override\n                    public void run() {\n                        Object o = m.take();\n                        System.out.println(\"\u53d6\u51fa\u7684\u5143\u7d20\u4e3a\uff1a\"+o);\n                    }\n                });\n        t2.start();\n        try {\n            Thread.sleep(10);\n            System.out.println(m.size());\n        } catch (InterruptedException e) {\n            \/\/ TODO Auto-generated catch block\n            e.printStackTrace();\n        }\n    }\n}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">43\u3001\u4e00\u4e2a\u7ebf\u7a0b\u8fd0\u884c\u65f6\u53d1\u751f\u5f02\u5e38\u4f1a\u600e\u6837\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u5f02\u5e38\u6ca1\u6709\u88ab\u6355\u83b7\u8be5\u7ebf\u7a0b\u5c06\u4f1a\u505c\u6b62\u6267\u884c\u3002Thread.UncaughtExceptionHandler\u662f\u7528\u4e8e\u5904\u7406\u672a\u6355\u83b7\u5f02\u5e38\u9020\u6210\u7ebf\u7a0b\u7a81\u7136\u4e2d\u65ad\u60c5\u51b5\u7684\u4e00\u4e2a\u5185\u5d4c\u63a5\u53e3\u3002\u5f53\u4e00\u4e2a\u672a\u6355\u83b7\u5f02\u5e38\u5c06\u9020\u6210\u7ebf\u7a0b\u4e2d\u65ad\u7684\u65f6\u5019 JVM \u4f1a\u4f7f\u7528 Thread.getUncaughtExceptionHandler()\u6765\u67e5\u8be2\u7ebf\u7a0b\u7684 UncaughtExceptionHandler \u5e76\u5c06\u7ebf\u7a0b\u548c\u5f02\u5e38\u4f5c\u4e3a\u53c2\u6570\u4f20\u9012\u7ed9handler \u7684 uncaughtException()\u65b9\u6cd5\u8fdb\u884c\u5904\u7406\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">44\u3001\u5982\u4f55\u5728\u4e24\u4e2a\u7ebf\u7a0b\u95f4\u5171\u4eab\u6570\u636e\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u4e24\u4e2a\u7ebf\u7a0b\u95f4\u5171\u4eab\u53d8\u91cf\u5373\u53ef\u5b9e\u73b0\u5171\u4eab\u3002\u4e00\u822c\u6765\u8bf4\uff0c\u5171\u4eab\u53d8\u91cf\u8981\u6c42\u53d8\u91cf\u672c\u8eab\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff0c\u7136\u540e\u5728\u7ebf\u7a0b\u5185\u4f7f\u7528\u7684\u65f6\u5019\uff0c\u5982\u679c\u6709\u5bf9\u5171\u4eab\u53d8\u91cf\u7684\u590d\u5408\u64cd\u4f5c\uff0c\u90a3\u4e48\u4e5f\u5f97\u4fdd\u8bc1\u590d\u5408\u64cd\u4f5c\u7684\u7ebf\u7a0b\u5b89\u5168\u6027\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">45\u3001Java \u4e2d notify \u548c notifyAll \u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">notify() \u65b9\u6cd5\u4e0d\u80fd\u5524\u9192\u67d0\u4e2a\u5177\u4f53\u7684\u7ebf\u7a0b\uff0c\u6240\u4ee5\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u5728\u7b49\u5f85\u7684\u65f6\u5019\u5b83\u624d\u6709\u7528\u6b66\u4e4b\u5730\u3002\u800c notifyAll()\u5524\u9192\u6240\u6709\u7ebf\u7a0b\u5e76\u5141\u8bb8\u4ed6\u4eec\u4e89\u593a\u9501\u786e\u4fdd\u4e86\u81f3\u5c11\u6709\u4e00\u4e2a\u7ebf\u7a0b\u80fd\u7ee7\u7eed\u8fd0\u884c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">46\u3001\u4e3a\u4ec0\u4e48 wait, notify \u548c notifyAll \u8fd9\u4e9b\u65b9\u6cd5\u4e0d\u5728 thread\u7c7b\u91cc\u9762\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e00\u4e2a\u5f88\u660e\u663e\u7684\u539f\u56e0\u662f JAVA \u63d0\u4f9b\u7684\u9501\u662f\u5bf9\u8c61\u7ea7\u7684\u800c\u4e0d\u662f\u7ebf\u7a0b\u7ea7\u7684\uff0c\u6bcf\u4e2a\u5bf9\u8c61\u90fd\u6709\u9501\uff0c\u901a\u8fc7\u7ebf\u7a0b\u83b7\u5f97\u3002\u7531\u4e8e wait\uff0cnotify \u548c notifyAll \u90fd\u662f\u9501\u7ea7\u522b\u7684\u64cd\u4f5c\uff0c\u6240\u4ee5\u628a\u4ed6\u4eec\u5b9a\u4e49\u5728 Object \u7c7b\u4e2d\u56e0\u4e3a\u9501\u5c5e\u4e8e\u5bf9\u8c61\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">47\u3001\u4ec0\u4e48\u662f ThreadLocal \u53d8\u91cf\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">ThreadLocal \u662f Java \u91cc\u4e00\u79cd\u7279\u6b8a\u7684\u53d8\u91cf\u3002\u6bcf\u4e2a\u7ebf\u7a0b\u90fd\u6709\u4e00\u4e2a ThreadLocal \u5c31\u662f\u6bcf\u4e2a\u7ebf\u7a0b\u90fd\u62e5\u6709\u4e86\u81ea\u5df1\u72ec\u7acb\u7684\u4e00\u4e2a\u53d8\u91cf\uff0c\u7ade\u4e89\u6761\u4ef6\u88ab\u5f7b\u5e95\u6d88\u9664\u4e86\u3002\u5b83\u662f\u4e3a\u521b\u5efa\u4ee3\u4ef7\u9ad8\u6602\u7684\u5bf9\u8c61\u83b7\u53d6\u7ebf\u7a0b\u5b89\u5168\u7684\u597d\u65b9\u6cd5\uff0c\u6bd4\u5982\u4f60\u53ef\u4ee5\u7528 ThreadLocal \u8ba9SimpleDateFormat \u53d8\u6210\u7ebf\u7a0b\u5b89\u5168\u7684\uff0c\u56e0\u4e3a\u90a3\u4e2a\u7c7b\u521b\u5efa\u4ee3\u4ef7\u9ad8\u6602\u4e14\u6bcf\u6b21\u8c03\u7528\u90fd\u9700\u8981\u521b\u5efa\u4e0d\u540c\u7684\u5b9e\u4f8b\u6240\u4ee5\u4e0d\u503c\u5f97\u5728\u5c40\u90e8\u8303\u56f4\u4f7f\u7528\u5b83\uff0c\u5982\u679c\u4e3a\u6bcf\u4e2a\u7ebf\u7a0b\u63d0\u4f9b\u4e00\u4e2a\u81ea\u5df1\u72ec\u6709\u7684\u53d8\u91cf\u62f7\u8d1d\uff0c\u5c06\u5927\u5927\u63d0\u9ad8\u6548\u7387\u3002\u9996\u5148\uff0c\u901a\u8fc7\u590d\u7528\u51cf\u5c11\u4e86\u4ee3\u4ef7\u9ad8\u6602\u7684\u5bf9\u8c61\u7684\u521b\u5efa\u4e2a\u6570\u3002\u5176\u6b21\uff0c\u4f60\u5728\u6ca1\u6709\u4f7f\u7528\u9ad8\u4ee3\u4ef7\u7684\u540c\u6b65\u6216\u8005\u4e0d\u53d8\u6027\u7684\u60c5\u51b5\u4e0b\u83b7\u5f97\u4e86\u7ebf\u7a0b\u5b89\u5168\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">48\u3001Java \u4e2d interrupted \u548c isInterrupted \u65b9\u6cd5\u7684\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">interruptinterrupt \u65b9\u6cd5\u7528\u4e8e\u4e2d\u65ad\u7ebf\u7a0b\u3002\u8c03\u7528\u8be5\u65b9\u6cd5\u7684\u7ebf\u7a0b\u7684\u72b6\u6001\u4e3a\u5c06\u88ab\u7f6e\u4e3a\u201d\u4e2d\u65ad\u201d\u72b6\u6001\u3002\u6ce8\u610f\uff1a\u7ebf\u7a0b\u4e2d\u65ad\u4ec5\u4ec5\u662f\u7f6e\u7ebf\u7a0b\u7684\u4e2d\u65ad\u72b6\u6001\u4f4d\uff0c\u4e0d\u4f1a\u505c\u6b62\u7ebf\u7a0b\u3002\u9700\u8981\u7528\u6237\u81ea\u5df1\u53bb\u76d1\u89c6\u7ebf\u7a0b\u7684\u72b6\u6001\u4e3a\u5e76\u505a\u5904\u7406\u3002\u652f\u6301\u7ebf\u7a0b\u4e2d\u65ad\u7684\u65b9\u6cd5\uff08\u4e5f\u5c31\u662f\u7ebf\u7a0b\u4e2d\u65ad\u540e\u4f1a\u629b\u51fainterruptedException \u7684\u65b9\u6cd5\uff09\u5c31\u662f\u5728\u76d1\u89c6\u7ebf\u7a0b\u7684\u4e2d\u65ad\u72b6\u6001\uff0c\u4e00\u65e6\u7ebf\u7a0b\u7684\u4e2d\u65ad\u72b6\u6001\u88ab\u7f6e\u4e3a\u201c\u4e2d\u65ad\u72b6\u6001\u201d\uff0c\u5c31\u4f1a\u629b\u51fa\u4e2d\u65ad\u5f02\u5e38\u3002interrupted\u67e5\u8be2\u5f53\u524d\u7ebf\u7a0b\u7684\u4e2d\u65ad\u72b6\u6001\uff0c\u5e76\u4e14\u6e05\u9664\u539f\u72b6\u6001\u3002\u5982\u679c\u4e00\u4e2a\u7ebf\u7a0b\u88ab\u4e2d\u65ad\u4e86\uff0c\u7b2c\u4e00\u6b21\u8c03\u7528 interrupted \u5219\u8fd4\u56de true\uff0c\u7b2c\u4e8c\u6b21\u548c\u540e\u9762\u7684\u5c31\u8fd4\u56de false \u4e86\u3002isInterrupted\u4ec5\u4ec5\u662f\u67e5\u8be2\u5f53\u524d\u7ebf\u7a0b\u7684\u4e2d\u65ad\u72b6\u6001<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">49\u3001\u4e3a\u4ec0\u4e48 wait \u548c notify \u65b9\u6cd5\u8981\u5728\u540c\u6b65\u5757\u4e2d\u8c03\u7528\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Java API \u5f3a\u5236\u8981\u6c42\u8fd9\u6837\u505a\uff0c\u5982\u679c\u4f60\u4e0d\u8fd9\u4e48\u505a\uff0c\u4f60\u7684\u4ee3\u7801\u4f1a\u629b\u51faIllegalMonitorStateException \u5f02\u5e38\u3002\u8fd8\u6709\u4e00\u4e2a\u539f\u56e0\u662f\u4e3a\u4e86\u907f\u514d wait \u548c notify\u4e4b\u95f4\u4ea7\u751f\u7ade\u6001\u6761\u4ef6\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">50\u3001\u4e3a\u4ec0\u4e48\u4f60\u5e94\u8be5\u5728\u5faa\u73af\u4e2d\u68c0\u67e5\u7b49\u5f85\u6761\u4ef6?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5904\u4e8e\u7b49\u5f85\u72b6\u6001\u7684\u7ebf\u7a0b\u53ef\u80fd\u4f1a\u6536\u5230\u9519\u8bef\u8b66\u62a5\u548c\u4f2a\u5524\u9192\uff0c\u5982\u679c\u4e0d\u5728\u5faa\u73af\u4e2d\u68c0\u67e5\u7b49\u5f85\u6761\u4ef6\uff0c\u7a0b\u5e8f\u5c31\u4f1a\u5728\u6ca1\u6709\u6ee1\u8db3\u7ed3\u675f\u6761\u4ef6\u7684\u60c5\u51b5\u4e0b\u9000\u51fa\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">51\u3001Java \u4e2d\u7684\u540c\u6b65\u96c6\u5408\u4e0e\u5e76\u53d1\u96c6\u5408\u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u540c\u6b65\u96c6\u5408\u4e0e\u5e76\u53d1\u96c6\u5408\u90fd\u4e3a\u591a\u7ebf\u7a0b\u548c\u5e76\u53d1\u63d0\u4f9b\u4e86\u5408\u9002\u7684\u7ebf\u7a0b\u5b89\u5168\u7684\u96c6\u5408\uff0c\u4e0d\u8fc7\u5e76\u53d1\u96c6\u5408\u7684\u53ef\u6269\u5c55\u6027\u66f4\u9ad8\u3002\u5728 Java1.5 \u4e4b\u524d\u7a0b\u5e8f\u5458\u4eec\u53ea\u6709\u540c\u6b65\u96c6\u5408\u6765\u7528\u4e14\u5728\u591a\u7ebf\u7a0b\u5e76\u53d1\u7684\u65f6\u5019\u4f1a\u5bfc\u81f4\u4e89\u7528\uff0c\u963b\u788d\u4e86\u7cfb\u7edf\u7684\u6269\u5c55\u6027\u3002Java5 \u4ecb\u7ecd\u4e86\u5e76\u53d1\u96c6\u5408\u50cfConcurrentHashMap\uff0c\u4e0d\u4ec5\u63d0\u4f9b\u7ebf\u7a0b\u5b89\u5168\u8fd8\u7528\u9501\u5206\u79bb\u548c\u5185\u90e8\u5206\u533a\u7b49\u73b0\u4ee3\u6280\u672f\u63d0\u9ad8\u4e86\u53ef\u6269\u5c55\u6027\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">52\u3001\u4ec0\u4e48\u662f\u7ebf\u7a0b\u6c60\uff1f \u4e3a\u4ec0\u4e48\u8981\u4f7f\u7528\u5b83\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u521b\u5efa\u7ebf\u7a0b\u8981\u82b1\u8d39\u6602\u8d35\u7684\u8d44\u6e90\u548c\u65f6\u95f4\uff0c\u5982\u679c\u4efb\u52a1\u6765\u4e86\u624d\u521b\u5efa\u7ebf\u7a0b\u90a3\u4e48\u54cd\u5e94\u65f6\u95f4\u4f1a\u53d8\u957f\uff0c\u800c\u4e14\u4e00\u4e2a\u8fdb\u7a0b\u80fd\u521b\u5efa\u7684\u7ebf\u7a0b\u6570\u6709\u9650\u3002\u4e3a\u4e86\u907f\u514d\u8fd9\u4e9b\u95ee\u9898\uff0c\u5728\u7a0b\u5e8f\u542f\u52a8\u7684\u65f6\u5019\u5c31\u521b\u5efa\u82e5\u5e72\u7ebf\u7a0b\u6765\u54cd\u5e94\u5904\u7406\uff0c\u5b83\u4eec\u88ab\u79f0\u4e3a\u7ebf\u7a0b\u6c60\uff0c\u91cc\u9762\u7684\u7ebf\u7a0b\u53eb\u5de5\u4f5c\u7ebf\u7a0b\u3002\u4eceJDK1.5 \u5f00\u59cb\uff0cJava API \u63d0\u4f9b\u4e86 Executor \u6846\u67b6\u8ba9\u4f60\u53ef\u4ee5\u521b\u5efa\u4e0d\u540c\u7684\u7ebf\u7a0b\u6c60\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">53\u3001\u600e\u4e48\u68c0\u6d4b\u4e00\u4e2a\u7ebf\u7a0b\u662f\u5426\u62e5\u6709\u9501\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728 java.lang.Thread \u4e2d\u6709\u4e00\u4e2a\u65b9\u6cd5\u53eb holdsLock()\uff0c\u5b83\u8fd4\u56de true \u5982\u679c\u5f53\u4e14\u4ec5\u5f53\u5f53\u524d\u7ebf\u7a0b\u62e5\u6709\u67d0\u4e2a\u5177\u4f53\u5bf9\u8c61\u7684\u9501\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">54\u3001\u4f60\u5982\u4f55\u5728 Java \u4e2d\u83b7\u53d6\u7ebf\u7a0b\u5806\u6808\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">kill -3 [java pid]\u4e0d\u4f1a\u5728\u5f53\u524d\u7ec8\u7aef\u8f93\u51fa\uff0c\u5b83\u4f1a\u8f93\u51fa\u5230\u4ee3\u7801\u6267\u884c\u7684\u6216\u6307\u5b9a\u7684\u5730\u65b9\u53bb\u3002\u6bd4\u5982\uff0ckill -3tomcat pid, \u8f93\u51fa\u5806\u6808\u5230 log \u76ee\u5f55\u4e0b\u3002Jstack [java pid]\u8fd9\u4e2a\u6bd4\u8f83\u7b80\u5355\uff0c\u5728\u5f53\u524d\u7ec8\u7aef\u663e\u793a\uff0c\u4e5f\u53ef\u4ee5\u91cd\u5b9a\u5411\u5230\u6307\u5b9a\u6587\u4ef6\u4e2d\u3002-JvisualVM\uff1aThread Dump\u4e0d\u505a\u8bf4\u660e\uff0c\u6253\u5f00 JvisualVM \u540e\uff0c\u90fd\u662f\u754c\u9762\u64cd\u4f5c\uff0c\u8fc7\u7a0b\u8fd8\u662f\u5f88\u7b80\u5355\u7684\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">55\u3001JVM \u4e2d\u54ea\u4e2a\u53c2\u6570\u662f\u7528\u6765\u63a7\u5236\u7ebf\u7a0b\u7684\u6808\u5806\u6808\u5c0f\u7684?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">-Xss \u6bcf\u4e2a\u7ebf\u7a0b\u7684\u6808\u5927\u5c0f<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">56\u3001Thread \u7c7b\u4e2d\u7684 yield \u65b9\u6cd5\u6709\u4ec0\u4e48\u4f5c\u7528\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u5f53\u524d\u7ebf\u7a0b\u4ece\u6267\u884c\u72b6\u6001\uff08\u8fd0\u884c\u72b6\u6001\uff09\u53d8\u4e3a\u53ef\u6267\u884c\u6001\uff08\u5c31\u7eea\u72b6\u6001\uff09\u3002\u5f53\u524d\u7ebf\u7a0b\u5230\u4e86\u5c31\u7eea\u72b6\u6001\uff0c\u90a3\u4e48\u63a5\u4e0b\u6765\u54ea\u4e2a\u7ebf\u7a0b\u4f1a\u4ece\u5c31\u7eea\u72b6\u6001\u53d8\u6210\u6267\u884c\u72b6\u6001\u5462\uff1f\u53ef\u80fd\u662f\u5f53\u524d\u7ebf\u7a0b\uff0c\u4e5f\u53ef\u80fd\u662f\u5176\u4ed6\u7ebf\u7a0b\uff0c\u770b\u7cfb\u7edf\u7684\u5206\u914d\u4e86\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">57\u3001Java \u4e2d ConcurrentHashMap \u7684\u5e76\u53d1\u5ea6\u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">ConcurrentHashMap \u628a\u5b9e\u9645 map \u5212\u5206\u6210\u82e5\u5e72\u90e8\u5206\u6765\u5b9e\u73b0\u5b83\u7684\u53ef\u6269\u5c55\u6027\u548c\u7ebf\u7a0b\u5b89\u5168\u3002\u8fd9\u79cd\u5212\u5206\u662f\u4f7f\u7528\u5e76\u53d1\u5ea6\u83b7\u5f97\u7684\uff0c\u5b83\u662f ConcurrentHashMap \u7c7b\u6784\u9020\u51fd\u6570\u7684\u4e00\u4e2a\u53ef\u9009\u53c2\u6570\uff0c\u9ed8\u8ba4\u503c\u4e3a 16\uff0c\u8fd9\u6837\u5728\u591a\u7ebf\u7a0b\u60c5\u51b5\u4e0b\u5c31\u80fd\u907f\u514d\u4e89\u7528\u3002\u5728 JDK8 \u540e\uff0c\u5b83\u6452\u5f03\u4e86 Segment\uff08\u9501\u6bb5\uff09\u7684\u6982\u5ff5\uff0c\u800c\u662f\u542f\u7528\u4e86\u4e00\u79cd\u5168\u65b0\u7684\u65b9\u5f0f\u5b9e\u73b0,\u5229\u7528 CAS \u7b97\u6cd5\u3002\u540c\u65f6\u52a0\u5165\u4e86\u66f4\u591a\u7684\u8f85\u52a9\u53d8\u91cf\u6765\u63d0\u9ad8\u5e76\u53d1\u5ea6\uff0c\u5177\u4f53\u5185\u5bb9\u8fd8\u662f\u67e5\u770b\u6e90\u7801\u5427\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">58\u3001Java \u4e2d Semaphore \u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Java \u4e2d\u7684 Semaphore \u662f\u4e00\u79cd\u65b0\u7684\u540c\u6b65\u7c7b\uff0c\u5b83\u662f\u4e00\u4e2a\u8ba1\u6570\u4fe1\u53f7\u3002\u4ece\u6982\u5ff5\u4e0a\u8bb2\uff0c\u4ece\u6982\u5ff5\u4e0a\u8bb2\uff0c\u4fe1\u53f7\u91cf\u7ef4\u62a4\u4e86\u4e00\u4e2a\u8bb8\u53ef\u96c6\u5408\u3002\u5982\u6709\u5fc5\u8981\uff0c\u5728\u8bb8\u53ef\u53ef\u7528\u524d\u4f1a\u963b\u585e\u6bcf\u4e00\u4e2aacquire()\uff0c\u7136\u540e\u518d\u83b7\u53d6\u8be5\u8bb8\u53ef\u3002\u6bcf\u4e2a release()\u6dfb\u52a0\u4e00\u4e2a\u8bb8\u53ef\uff0c\u4ece\u800c\u53ef\u80fd\u91ca\u653e\u4e00\u4e2a\u6b63\u5728\u963b\u585e\u7684\u83b7\u53d6\u8005\u3002\u4f46\u662f\uff0c\u4e0d\u4f7f\u7528\u5b9e\u9645\u7684\u8bb8\u53ef\u5bf9\u8c61\uff0cSemaphore \u53ea\u5bf9\u53ef\u7528\u8bb8\u53ef\u7684\u53f7\u7801\u8fdb\u884c\u8ba1\u6570\uff0c\u5e76\u91c7\u53d6\u76f8\u5e94\u7684\u884c\u52a8\u3002\u4fe1\u53f7\u91cf\u5e38\u5e38\u7528\u4e8e\u591a\u7ebf\u7a0b\u7684\u4ee3\u7801\u4e2d\uff0c\u6bd4\u5982\u6570\u636e\u5e93\u8fde\u63a5\u6c60\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">59\u3001Java \u7ebf\u7a0b\u6c60\u4e2d submit() \u548c execute()\u65b9\u6cd5\u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e24\u4e2a\u65b9\u6cd5\u90fd\u53ef\u4ee5\u5411\u7ebf\u7a0b\u6c60\u63d0\u4ea4\u4efb\u52a1\uff0cexecute()\u65b9\u6cd5\u7684\u8fd4\u56de\u7c7b\u578b\u662f void\uff0c\u5b83\u5b9a\u4e49\u5728Executor \u63a5\u53e3\u4e2d\u3002\u800c submit()\u65b9\u6cd5\u53ef\u4ee5\u8fd4\u56de\u6301\u6709\u8ba1\u7b97\u7ed3\u679c\u7684 Future \u5bf9\u8c61\uff0c\u5b83\u5b9a\u4e49\u5728ExecutorService \u63a5\u53e3\u4e2d\uff0c\u5b83\u6269\u5c55\u4e86 Executor \u63a5\u53e3\uff0c\u5176\u5b83\u7ebf\u7a0b\u6c60\u7c7b\u50cfThreadPoolExecutor \u548c ScheduledThreadPoolExecutor \u90fd\u6709\u8fd9\u4e9b\u65b9\u6cd5\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">60\u3001\u4ec0\u4e48\u662f\u963b\u585e\u5f0f\u65b9\u6cd5\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u963b\u585e\u5f0f\u65b9\u6cd5\u662f\u6307\u7a0b\u5e8f\u4f1a\u4e00\u76f4\u7b49\u5f85\u8be5\u65b9\u6cd5\u5b8c\u6210\u671f\u95f4\u4e0d\u505a\u5176\u4ed6\u4e8b\u60c5\uff0cServerSocket \u7684accept()\u65b9\u6cd5\u5c31\u662f\u4e00\u76f4\u7b49\u5f85\u5ba2\u6237\u7aef\u8fde\u63a5\u3002\u8fd9\u91cc\u7684\u963b\u585e\u662f\u6307\u8c03\u7528\u7ed3\u679c\u8fd4\u56de\u4e4b\u524d\uff0c\u5f53\u524d\u7ebf\u7a0b\u4f1a\u88ab\u6302\u8d77\uff0c\u76f4\u5230\u5f97\u5230\u7ed3\u679c\u4e4b\u540e\u624d\u4f1a\u8fd4\u56de\u3002\u6b64\u5916\uff0c\u8fd8\u6709\u5f02\u6b65\u548c\u975e\u963b\u585e\u5f0f\u65b9\u6cd5\u5728\u4efb\u52a1\u5b8c\u6210\u524d\u5c31\u8fd4\u56de\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">61\u3001Java \u4e2d\u7684 ReadWriteLock \u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8bfb\u5199\u9501\u662f\u7528\u6765\u63d0\u5347\u5e76\u53d1\u7a0b\u5e8f\u6027\u80fd\u7684\u9501\u5206\u79bb\u6280\u672f\u7684\u6210\u679c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">62\u3001volatile \u53d8\u91cf\u548c atomic \u53d8\u91cf\u6709\u4ec0\u4e48\u4e0d\u540c\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Volatile \u53d8\u91cf\u53ef\u4ee5\u786e\u4fdd\u5148\u884c\u5173\u7cfb\uff0c\u5373\u5199\u64cd\u4f5c\u4f1a\u53d1\u751f\u5728\u540e\u7eed\u7684\u8bfb\u64cd\u4f5c\u4e4b\u524d, \u4f46\u5b83\u5e76\u4e0d\u80fd\u4fdd\u8bc1\u539f\u5b50\u6027\u3002\u4f8b\u5982\u7528 volatile \u4fee\u9970 count \u53d8\u91cf\u90a3\u4e48 count++ \u64cd\u4f5c\u5c31\u4e0d\u662f\u539f\u5b50\u6027\u7684\u3002\u800c AtomicInteger \u7c7b\u63d0\u4f9b\u7684 atomic \u65b9\u6cd5\u53ef\u4ee5\u8ba9\u8fd9\u79cd\u64cd\u4f5c\u5177\u6709\u539f\u5b50\u6027\u5982getAndIncrement()\u65b9\u6cd5\u4f1a\u539f\u5b50\u6027\u7684\u8fdb\u884c\u589e\u91cf\u64cd\u4f5c\u628a\u5f53\u524d\u503c\u52a0\u4e00\uff0c\u5176\u5b83\u6570\u636e\u7c7b\u578b\u548c\u5f15\u7528\u53d8\u91cf\u4e5f\u53ef\u4ee5\u8fdb\u884c\u76f8\u4f3c\u64cd\u4f5c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">63\u3001\u53ef\u4ee5\u76f4\u63a5\u8c03\u7528 Thread \u7c7b\u7684 run ()\u65b9\u6cd5\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u7136\u53ef\u4ee5\u3002\u4f46\u662f\u5982\u679c\u6211\u4eec\u8c03\u7528\u4e86 Thread \u7684 run()\u65b9\u6cd5\uff0c\u5b83\u7684\u884c\u4e3a\u5c31\u4f1a\u548c\u666e\u901a\u7684\u65b9\u6cd5\u4e00\u6837\uff0c\u4f1a\u5728\u5f53\u524d\u7ebf\u7a0b\u4e2d\u6267\u884c\u3002\u4e3a\u4e86\u5728\u65b0\u7684\u7ebf\u7a0b\u4e2d\u6267\u884c\u6211\u4eec\u7684\u4ee3\u7801\uff0c\u5fc5\u987b\u4f7f\u7528Thread.start()\u65b9\u6cd5\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">64\u3001\u5982\u4f55\u8ba9\u6b63\u5728\u8fd0\u884c\u7684\u7ebf\u7a0b\u6682\u505c\u4e00\u6bb5\u65f6\u95f4\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 Thread \u7c7b\u7684 Sleep()\u65b9\u6cd5\u8ba9\u7ebf\u7a0b\u6682\u505c\u4e00\u6bb5\u65f6\u95f4\u3002\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u8fd9\u5e76\u4e0d\u4f1a\u8ba9\u7ebf\u7a0b\u7ec8\u6b62\uff0c\u4e00\u65e6\u4ece\u4f11\u7720\u4e2d\u5524\u9192\u7ebf\u7a0b\uff0c\u7ebf\u7a0b\u7684\u72b6\u6001\u5c06\u4f1a\u88ab\u6539\u53d8\u4e3a Runnable\uff0c\u5e76\u4e14\u6839\u636e\u7ebf\u7a0b\u8c03\u5ea6\uff0c\u5b83\u5c06\u5f97\u5230\u6267\u884c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">65\u3001\u4f60\u5bf9\u7ebf\u7a0b\u4f18\u5148\u7ea7\u7684\u7406\u89e3\u662f\u4ec0\u4e48\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6bcf\u4e00\u4e2a\u7ebf\u7a0b\u90fd\u662f\u6709\u4f18\u5148\u7ea7\u7684\uff0c\u4e00\u822c\u6765\u8bf4\uff0c\u9ad8\u4f18\u5148\u7ea7\u7684\u7ebf\u7a0b\u5728\u8fd0\u884c\u65f6\u4f1a\u5177\u6709\u4f18\u5148\u6743\uff0c\u4f46\u8fd9\u4f9d\u8d56\u4e8e\u7ebf\u7a0b\u8c03\u5ea6\u7684\u5b9e\u73b0\uff0c\u8fd9\u4e2a\u5b9e\u73b0\u662f\u548c\u64cd\u4f5c\u7cfb\u7edf\u76f8\u5173\u7684(OS dependent)\u3002\u6211\u4eec\u53ef\u4ee5\u5b9a\u4e49\u7ebf\u7a0b\u7684\u4f18\u5148\u7ea7\uff0c\u4f46\u662f\u8fd9\u5e76\u4e0d\u80fd\u4fdd\u8bc1\u9ad8\u4f18\u5148\u7ea7\u7684\u7ebf\u7a0b\u4f1a\u5728\u4f4e\u4f18\u5148\u7ea7\u7684\u7ebf\u7a0b\u524d\u6267\u884c\u3002\u7ebf\u7a0b\u4f18\u5148\u7ea7\u662f\u4e00\u4e2a int \u53d8\u91cf(\u4ece 1-10)\uff0c1 \u4ee3\u8868\u6700\u4f4e\u4f18\u5148\u7ea7\uff0c10 \u4ee3\u8868\u6700\u9ad8\u4f18\u5148\u7ea7\u3002java \u7684\u7ebf\u7a0b\u4f18\u5148\u7ea7\u8c03\u5ea6\u4f1a\u59d4\u6258\u7ed9\u64cd\u4f5c\u7cfb\u7edf\u53bb\u5904\u7406\uff0c\u6240\u4ee5\u4e0e\u5177\u4f53\u7684\u64cd\u4f5c\u7cfb\u7edf\u4f18\u5148\u7ea7\u6709\u5173\uff0c\u5982\u975e\u7279\u522b\u9700\u8981\uff0c\u4e00\u822c\u65e0\u9700\u8bbe\u7f6e\u7ebf\u7a0b\u4f18\u5148\u7ea7\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">66\u3001\u4ec0\u4e48\u662f\u7ebf\u7a0b\u8c03\u5ea6\u5668(Thread Scheduler)\u548c\u65f6\u95f4\u5206\u7247(Time Slicing )\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ebf\u7a0b\u8c03\u5ea6\u5668\u662f\u4e00\u4e2a\u64cd\u4f5c\u7cfb\u7edf\u670d\u52a1\uff0c\u5b83\u8d1f\u8d23\u4e3a Runnable \u72b6\u6001\u7684\u7ebf\u7a0b\u5206\u914d CPU \u65f6\u95f4\u3002\u4e00\u65e6\u6211\u4eec\u521b\u5efa\u4e00\u4e2a\u7ebf\u7a0b\u5e76\u542f\u52a8\u5b83\uff0c\u5b83\u7684\u6267\u884c\u4fbf\u4f9d\u8d56\u4e8e\u7ebf\u7a0b\u8c03\u5ea6\u5668\u7684\u5b9e\u73b0\u3002\u540c\u4e0a\u4e00\u4e2a\u95ee\u9898\uff0c\u7ebf\u7a0b\u8c03\u5ea6\u5e76\u4e0d\u53d7\u5230 Java \u865a\u62df\u673a\u63a7\u5236\uff0c\u6240\u4ee5\u7531\u5e94\u7528\u7a0b\u5e8f\u6765\u63a7\u5236\u5b83\u662f\u66f4\u597d\u7684\u9009\u62e9\uff08\u4e5f\u5c31\u662f\u8bf4\u4e0d\u8981\u8ba9\u4f60\u7684\u7a0b\u5e8f\u4f9d\u8d56\u4e8e\u7ebf\u7a0b\u7684\u4f18\u5148\u7ea7\uff09\u3002\u65f6\u95f4\u5206\u7247\u662f\u6307\u5c06\u53ef\u7528\u7684 CPU \u65f6\u95f4\u5206\u914d\u7ed9\u53ef\u7528\u7684 Runnable \u7ebf\u7a0b\u7684\u8fc7\u7a0b\u3002\u5206\u914d CPU\u65f6\u95f4\u53ef\u4ee5\u57fa\u4e8e\u7ebf\u7a0b\u4f18\u5148\u7ea7\u6216\u8005\u7ebf\u7a0b\u7b49\u5f85\u7684\u65f6\u95f4\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">67\u3001\u4f60\u5982\u4f55\u786e\u4fdd main()\u65b9\u6cd5\u6240\u5728\u7684\u7ebf\u7a0b\u662f Java \u7a0b\u5e8f\u6700\u540e\u7ed3\u675f\u7684\u7ebf\u7a0b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 Thread \u7c7b\u7684 join()\u65b9\u6cd5\u6765\u786e\u4fdd\u6240\u6709\u7a0b\u5e8f\u521b\u5efa\u7684\u7ebf\u7a0b\u5728 main()\u65b9\u6cd5\u9000\u51fa\u524d\u7ed3\u675f\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">68\u3001\u7ebf\u7a0b\u4e4b\u95f4\u662f\u5982\u4f55\u901a\u4fe1\u7684\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u7ebf\u7a0b\u95f4\u662f\u53ef\u4ee5\u5171\u4eab\u8d44\u6e90\u65f6\uff0c\u7ebf\u7a0b\u95f4\u901a\u4fe1\u662f\u534f\u8c03\u5b83\u4eec\u7684\u91cd\u8981\u7684\u624b\u6bb5\u3002Object \u7c7b\u4e2dwait()\\notify()\\notifyAll()\u65b9\u6cd5\u53ef\u4ee5\u7528\u4e8e\u7ebf\u7a0b\u95f4\u901a\u4fe1\u5173\u4e8e\u8d44\u6e90\u7684\u9501\u7684\u72b6\u6001\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">69\u3001\u4e3a\u4ec0\u4e48\u7ebf\u7a0b\u901a\u4fe1\u7684\u65b9\u6cd5 wait(), notify()\u548c notifyAll()\u88ab\u5b9a\u4e49\u5728 Object \u7c7b\u91cc\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Java \u7684\u6bcf\u4e2a\u5bf9\u8c61\u4e2d\u90fd\u6709\u4e00\u4e2a\u9501(monitor\uff0c\u4e5f\u53ef\u4ee5\u6210\u4e3a\u76d1\u89c6\u5668) \u5e76\u4e14 wait()\uff0cnotify()\u7b49\u65b9\u6cd5\u7528\u4e8e\u7b49\u5f85\u5bf9\u8c61\u7684\u9501\u6216\u8005\u901a\u77e5\u5176\u4ed6\u7ebf\u7a0b\u5bf9\u8c61\u7684\u76d1\u89c6\u5668\u53ef\u7528\u3002\u5728 Java \u7684\u7ebf\u7a0b\u4e2d\u5e76\u6ca1\u6709\u53ef\u4f9b\u4efb\u4f55\u5bf9\u8c61\u4f7f\u7528\u7684\u9501\u548c\u540c\u6b65\u5668\u3002\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u8fd9\u4e9b\u65b9\u6cd5\u662f Object \u7c7b\u7684\u4e00\u90e8\u5206\uff0c\u8fd9\u6837 Java \u7684\u6bcf\u4e00\u4e2a\u7c7b\u90fd\u6709\u7528\u4e8e\u7ebf\u7a0b\u95f4\u901a\u4fe1\u7684\u57fa\u672c\u65b9\u6cd5\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">70\u3001\u4e3a\u4ec0\u4e48 wait(), notify()\u548c notifyAll ()\u5fc5\u987b\u5728\u540c\u6b65\u65b9\u6cd5\u6216\u8005\u540c\u6b65\u5757\u4e2d\u88ab\u8c03\u7528\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u9700\u8981\u8c03\u7528\u5bf9\u8c61\u7684 wait()\u65b9\u6cd5\u7684\u65f6\u5019\uff0c\u8fd9\u4e2a\u7ebf\u7a0b\u5fc5\u987b\u62e5\u6709\u8be5\u5bf9\u8c61\u7684\u9501\uff0c\u63a5\u7740\u5b83\u5c31\u4f1a\u91ca\u653e\u8fd9\u4e2a\u5bf9\u8c61\u9501\u5e76\u8fdb\u5165\u7b49\u5f85\u72b6\u6001\u76f4\u5230\u5176\u4ed6\u7ebf\u7a0b\u8c03\u7528\u8fd9\u4e2a\u5bf9\u8c61\u4e0a\u7684 notify()\u65b9\u6cd5\u3002\u540c\u6837\u7684\uff0c\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u9700\u8981\u8c03\u7528\u5bf9\u8c61\u7684 notify()\u65b9\u6cd5\u65f6\uff0c\u5b83\u4f1a\u91ca\u653e\u8fd9\u4e2a\u5bf9\u8c61\u7684\u9501\uff0c\u4ee5\u4fbf\u5176\u4ed6\u5728\u7b49\u5f85\u7684\u7ebf\u7a0b\u5c31\u53ef\u4ee5\u5f97\u5230\u8fd9\u4e2a\u5bf9\u8c61\u9501\u3002\u7531\u4e8e\u6240\u6709\u7684\u8fd9\u4e9b\u65b9\u6cd5\u90fd\u9700\u8981\u7ebf\u7a0b\u6301\u6709\u5bf9\u8c61\u7684\u9501\uff0c\u8fd9\u6837\u5c31\u53ea\u80fd\u901a\u8fc7\u540c\u6b65\u6765\u5b9e\u73b0\uff0c\u6240\u4ee5\u4ed6\u4eec\u53ea\u80fd\u5728\u540c\u6b65\u65b9\u6cd5\u6216\u8005\u540c\u6b65\u5757\u4e2d\u88ab\u8c03\u7528\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">71\u3001\u4e3a\u4ec0\u4e48 Thread \u7c7b\u7684 sleep()\u548c yield ()\u65b9\u6cd5\u662f\u9759\u6001\u7684\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Thread \u7c7b\u7684 sleep()\u548c yield()\u65b9\u6cd5\u5c06\u5728\u5f53\u524d\u6b63\u5728\u6267\u884c\u7684\u7ebf\u7a0b\u4e0a\u8fd0\u884c\u3002\u6240\u4ee5\u5728\u5176\u4ed6\u5904\u4e8e\u7b49\u5f85\u72b6\u6001\u7684\u7ebf\u7a0b\u4e0a\u8c03\u7528\u8fd9\u4e9b\u65b9\u6cd5\u662f\u6ca1\u6709\u610f\u4e49\u7684\u3002\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u8fd9\u4e9b\u65b9\u6cd5\u662f\u9759\u6001\u7684\u3002\u5b83\u4eec\u53ef\u4ee5\u5728\u5f53\u524d\u6b63\u5728\u6267\u884c\u7684\u7ebf\u7a0b\u4e2d\u5de5\u4f5c\uff0c\u5e76\u907f\u514d\u7a0b\u5e8f\u5458\u9519\u8bef\u7684\u8ba4\u4e3a\u53ef\u4ee5\u5728\u5176\u4ed6\u975e\u8fd0\u884c\u7ebf\u7a0b\u8c03\u7528\u8fd9\u4e9b\u65b9\u6cd5\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">72\u3001\u5982\u4f55\u786e\u4fdd\u7ebf\u7a0b\u5b89\u5168\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728 Java \u4e2d\u53ef\u4ee5\u6709\u5f88\u591a\u65b9\u6cd5\u6765\u4fdd\u8bc1\u7ebf\u7a0b\u5b89\u5168\u2014\u2014\u540c\u6b65\uff0c\u4f7f\u7528\u539f\u5b50\u7c7b(atomic concurrent 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class=\"wp-block-paragraph\">\u540c\u6b65\u5757\u662f\u66f4\u597d\u7684\u9009\u62e9\uff0c\u56e0\u4e3a\u5b83\u4e0d\u4f1a\u9501\u4f4f\u6574\u4e2a\u5bf9\u8c61\uff08\u5f53\u7136\u4f60\u4e5f\u53ef\u4ee5\u8ba9\u5b83\u9501\u4f4f\u6574\u4e2a\u5bf9\u8c61\uff09\u3002\u540c\u6b65\u65b9\u6cd5\u4f1a\u9501\u4f4f\u6574\u4e2a\u5bf9\u8c61\uff0c\u54ea\u6015\u8fd9\u4e2a\u7c7b\u4e2d\u6709\u591a\u4e2a\u4e0d\u76f8\u5173\u8054\u7684\u540c\u6b65\u5757\uff0c\u8fd9\u901a\u5e38\u4f1a\u5bfc\u81f4\u4ed6\u4eec\u505c\u6b62\u6267\u884c\u5e76\u9700\u8981\u7b49\u5f85\u83b7\u5f97\u8fd9\u4e2a\u5bf9\u8c61\u4e0a\u7684\u9501\u3002\u540c\u6b65\u5757\u66f4\u8981\u7b26\u5408\u5f00\u653e\u8c03\u7528\u7684\u539f\u5219\uff0c\u53ea\u5728\u9700\u8981\u9501\u4f4f\u7684\u4ee3\u7801\u5757\u9501\u4f4f\u76f8\u5e94\u7684\u5bf9\u8c61\uff0c\u8fd9\u6837\u4ece\u4fa7\u9762\u6765\u8bf4\u4e5f\u53ef\u4ee5\u907f\u514d\u6b7b\u9501\u3002<\/p>\n\n\n\n<h2 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[&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[472,546,579,62,410],"class_list":["post-4777","post","type-post","status-publish","format-standard","hentry","category-java","tag-rest","tag-546","tag-579","tag-62","tag-410"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4777","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4777"}],"version-history":[{"count":1,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4777\/revisions"}],"predecessor-version":[{"id":4778,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4777\/revisions\/4778"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4777"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4777"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4777"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}