{"id":2734,"date":"2018-04-30T15:44:14","date_gmt":"2018-04-30T07:44:14","guid":{"rendered":"http:\/\/www.xttblog.com\/?p=2734"},"modified":"2018-04-30T15:44:14","modified_gmt":"2018-04-30T07:44:14","slug":"java%e4%b8%ad%e5%9b%9b%e7%a7%8d%e5%bc%95%e7%94%a8%ef%bc%8c%e5%bc%ba%e5%bc%95%e7%94%a8%ef%bc%8c%e8%bd%af%e5%bc%95%e7%94%a8%ef%bc%8c%e5%bc%b1%e5%bc%95%e7%94%a8%ef%bc%8c%e8%99%9a%e5%bc%95%e7%94%a8","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=2734","title":{"rendered":"JAVA\u4e2d\u56db\u79cd\u5f15\u7528\uff0c\u5f3a\u5f15\u7528\uff0c\u8f6f\u5f15\u7528\uff0c\u5f31\u5f15\u7528\uff0c\u865a\u5f15\u7528\u6559\u7a0b"},"content":{"rendered":"<p>\n\tJava \u4e2d\u5171\u6709\u56db\u79cd\u5f15\u7528\u3002\u5305\u62ec\u5f3a\u5f15\u7528\uff0c\u8f6f\u5f15\u7528\uff0c\u5f31\u5f15\u7528\uff0c\u865a\u5f15\u7528\u3002\u672c\u6587\u5c06\u5206\u522b\u4ecb\u7ecd\u5b83\u4eec\u3002\n<\/p>\n<h2>\n\t\u5f3a\u5f15\u7528<br \/>\n<\/h2>\n<p>\n\t\u5f3a\u5f15\u7528\uff08StrongReference\uff09\u3002\n<\/p>\n<p>\n\t\u53ea\u8981\u5f15\u7528\u5b58\u5728\uff0c\u5783\u573e\u56de\u6536\u5668\u6c38\u8fdc\u4e0d\u4f1a\u56de\u6536\u3002\n<\/p>\n<pre class=\"brush:java;\">\r\nObject obj = new Object();\r\n\/\/\u53ef\u76f4\u63a5\u901a\u8fc7obj\u53d6\u5f97\u5bf9\u5e94\u7684\u5bf9\u8c61 \u5982obj.equels(new Object());<\/pre>\n<p>\n\t\u800c\u8fd9\u6837 obj \u5bf9\u8c61\u5bf9\u540e\u9762new Object\u7684\u4e00\u4e2a\u5f3a\u5f15\u7528\uff0c\u53ea\u6709\u5f53 obj \u8fd9\u4e2a\u5f15\u7528\u88ab\u91ca\u653e\u4e4b\u540e\uff0c\u5bf9\u8c61\u624d\u4f1a\u88ab\u91ca\u653e\u6389\uff0c\u8fd9\u4e5f\u662f\u6211\u4eec\u7ecf\u5e38\u6240\u7528\u5230\u7684\u7f16\u7801\u5f62\u5f0f\u3002\n<\/p>\n<h2>\n\t\u8f6f\u5f15\u7528\uff08SoftReference\uff09<br \/>\n<\/h2>\n<p>\n\t\u8f6f\u5f15\u7528\u4e3a\u975e\u5fc5\u987b\u5f15\u7528\uff0c\u5185\u5b58\u6ea2\u51fa\u4e4b\u524d\u8fdb\u884c\u56de\u6536\uff0c\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u4ee3\u7801\u5b9e\u73b0\u3002\n<\/p>\n<pre class=\"brush:java;\">\r\nObject obj = new Object();\r\nSoftReference&lt;Object&gt; sf = new SoftReference&lt;Object&gt;(obj);\r\nobj = null;\r\nsf.get();\/\/\u6709\u65f6\u5019\u4f1a\u8fd4\u56denull<\/pre>\n<p>\n\t\u8fd9\u65f6\u5019sf\u662f\u5bf9obj\u7684\u4e00\u4e2a\u8f6f\u5f15\u7528\uff0c\u901a\u8fc7sf.get()\u65b9\u6cd5\u53ef\u4ee5\u53d6\u5230\u8fd9\u4e2a\u5bf9\u8c61\uff0c\u5f53\u7136\uff0c\u5f53\u8fd9\u4e2a\u5bf9\u8c61\u88ab\u6807\u8bb0\u4e3a\u9700\u8981\u56de\u6536\u7684\u5bf9\u8c61\u65f6\uff0c\u5219\u8fd4\u56denull\uff1b\n<\/p>\n<p>\n\t\u8f6f\u5f15\u7528\u4e3b\u8981\u7528\u6237\u5b9e\u73b0\u7c7b\u4f3c\u7f13\u5b58\u7684\u529f\u80fd\uff0c\u5728\u5185\u5b58\u8db3\u591f\u7684\u60c5\u51b5\u4e0b\u76f4\u63a5\u901a\u8fc7\u8f6f\u5f15\u7528\u53d6\u503c\uff0c\u65e0\u9700\u4ece\u7e41\u5fd9\u7684\u771f\u5b9e\u6765\u6e90\u67e5\u8be2\u6570\u636e\uff0c\u63d0\u5347\u901f\u5ea6\uff1b\u5f53\u5185\u5b58\u4e0d\u8db3\u65f6\uff0c\u81ea\u52a8\u5220\u9664\u8fd9\u90e8\u5206\u7f13\u5b58\u6570\u636e\uff0c\u4ece\u771f\u6b63\u7684\u6765\u6e90\u67e5\u8be2\u8fd9\u4e9b\u6570\u636e\u3002\n<\/p>\n<pre class=\"brush:java;\">\r\nMyObject aRef = new MyObject();\r\nSoftReference aSoftRef=new SoftReference(aRef); <\/pre>\n<p>\n\t\u6b64\u65f6\uff0c\u5bf9\u4e8e\u8fd9\u4e2aMyObject\u5bf9\u8c61\uff0c\u6709\u4e24\u4e2a\u5f15\u7528\u8def\u5f84\uff0c\u4e00\u4e2a\u662f\u6765\u81eaSoftReference\u5bf9\u8c61\u7684\u8f6f\u5f15\u7528\uff0c\u4e00\u4e2a\u6765\u81ea\u53d8\u91cfaReference\u7684\u5f3a\u5f15\u7528\uff0c\u6240\u4ee5\u8fd9\u4e2aMyObject\u5bf9\u8c61\u662f\u5f3a\u53ef\u53ca\u5bf9\u8c61\u3002<br \/>\n\t\u968f\u5373\uff0c\u6211\u4eec\u53ef\u4ee5\u7ed3\u675faReference\u5bf9\u8fd9\u4e2aMyObject\u5b9e\u4f8b\u7684\u5f3a\u5f15\u7528\uff1a\n<\/p>\n<pre class=\"brush:java;\">\r\naRef = null;<\/pre>\n<p>\n\t\u6b64\u540e\uff0c\u8fd9\u4e2aMyObject\u5bf9\u8c61\u6210\u4e3a\u4e86\u8f6f\u53ef\u53ca\u5bf9\u8c61\u3002\u5728\u56de\u6536\u8fd9\u4e9b\u5bf9\u8c61\u4e4b\u524d\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\uff1a\n<\/p>\n<pre class=\"brush:java;\">\r\nMyObject anotherRef=(MyObject)aSoftRef.get();<\/pre>\n<p>\n\t\u91cd\u65b0\u83b7\u5f97\u5bf9\u8be5\u5b9e\u4f8b\u7684\u5f3a\u5f15\u7528\u3002\u800c\u56de\u6536\u4e4b\u540e\uff0c\u8c03\u7528get()\u65b9\u6cd5\u5c31\u53ea\u80fd\u5f97\u5230null\u4e86\u3002\n<\/p>\n<h2>\n\t\u5f31\u5f15\u7528<br \/>\n<\/h2>\n<p>\n\t\u7b2c\u4e8c\u6b21\u5783\u573e\u56de\u6536\u65f6\u56de\u6536\uff0c\u53ef\u4ee5\u901a\u8fc7\u5982\u4e0b\u4ee3\u7801\u5b9e\u73b0\u3002\n<\/p>\n<pre class=\"brush:java;\">\r\nObject obj = new Object();\r\nWeakReference&lt;Object&gt; wf = new WeakReference&lt;Object&gt;(obj);\r\nobj = null;\r\nwf.get();\/\/\u6709\u65f6\u5019\u4f1a\u8fd4\u56denull\r\nwf.isEnQueued();\/\/\u8fd4\u56de\u662f\u5426\u88ab\u5783\u573e\u56de\u6536\u5668\u6807\u8bb0\u4e3a\u5373\u5c06\u56de\u6536\u7684\u5783\u573e<\/pre>\n<p>\n\t\u5f31\u5f15\u7528\u662f\u5728\u7b2c\u4e8c\u6b21\u5783\u573e\u56de\u6536\u65f6\u56de\u6536\uff0c\u77ed\u65f6\u95f4\u5185\u901a\u8fc7\u5f31\u5f15\u7528\u53d6\u5bf9\u5e94\u7684\u6570\u636e\uff0c\u53ef\u4ee5\u53d6\u5230\uff0c\u5f53\u6267\u884c\u8fc7\u7b2c\u4e8c\u6b21\u5783\u573e\u56de\u6536\u65f6\uff0c\u5c06\u8fd4\u56denull\u3002<br \/>\n\t\u5f31\u5f15\u7528\u4e3b\u8981\u7528\u4e8e\u76d1\u63a7\u5bf9\u8c61\u662f\u5426\u5df2\u7ecf\u88ab\u5783\u573e\u56de\u6536\u5668\u6807\u8bb0\u4e3a\u5373\u5c06\u56de\u6536\u7684\u5783\u573e\uff0c\u53ef\u4ee5\u901a\u8fc7\u5f31\u5f15\u7528\u7684isEnQueued\u65b9\u6cd5\u8fd4\u56de\u5bf9\u8c61\u662f\u5426\u88ab\u5783\u573e\u56de\u6536\u5668\u6807\u8bb0\u3002\n<\/p>\n<h2>\n\t\u865a\u5f15\u7528<br \/>\n<\/h2>\n<p>\n\t\u5783\u573e\u56de\u6536\u65f6\u56de\u6536\uff0c\u65e0\u6cd5\u901a\u8fc7\u5f15\u7528\u53d6\u5230\u5bf9\u8c61\u503c\uff0c\u53ef\u4ee5\u901a\u8fc7\u5982\u4e0b\u4ee3\u7801\u5b9e\u73b0\u3002\n<\/p>\n<pre class=\"brush:java;\">\r\nObject obj = new Object();\r\nPhantomReference&lt;Object&gt; pf = new PhantomReference&lt;Object&gt;(obj);\r\nobj=null;\r\npf.get();\/\/\u6c38\u8fdc\u8fd4\u56denull\r\npf.isEnQueued();\/\/\u8fd4\u56de\u662f\u5426\u4ece\u5185\u5b58\u4e2d\u5df2\u7ecf\u5220\u9664<\/pre>\n<p>\n\t\u865a\u5f15\u7528\u662f\u6bcf\u6b21\u5783\u573e\u56de\u6536\u7684\u65f6\u5019\u90fd\u4f1a\u88ab\u56de\u6536\uff0c\u901a\u8fc7\u865a\u5f15\u7528\u7684get\u65b9\u6cd5\u6c38\u8fdc\u83b7\u53d6\u5230\u7684\u6570\u636e\u4e3anull\uff0c\u56e0\u6b64\u4e5f\u88ab\u6210\u4e3a\u5e7d\u7075\u5f15\u7528\u3002<br \/>\n\t\u865a\u5f15\u7528\u4e3b\u8981\u7528\u4e8e\u68c0\u6d4b\u5bf9\u8c61\u662f\u5426\u5df2\u7ecf\u4ece\u5185\u5b58\u4e2d\u5220\u9664\u3002<br \/>\n\t\u865a\u5f15\u7528\u4e3b\u8981\u7528\u6765\u8ddf\u8e2a\u5bf9\u8c61\u88ab\u5783\u573e\u56de\u6536\u5668\u56de\u6536\u7684\u6d3b\u52a8\u3002\u865a\u5f15\u7528\u4e0e\u8f6f\u5f15\u7528\u548c\u5f31\u5f15\u7528\u7684\u4e00\u4e2a\u533a\u522b\u5728\u4e8e\uff1a\u865a\u5f15\u7528\u5fc5\u987b\u548c\u5f15\u7528\u961f\u5217 \uff08ReferenceQueue\uff09\u8054\u5408\u4f7f\u7528\u3002\u5f53\u5783\u573e\u56de\u6536\u5668\u51c6\u5907\u56de\u6536\u4e00\u4e2a\u5bf9\u8c61\u65f6\uff0c\u5982\u679c\u53d1\u73b0\u5b83\u8fd8\u6709\u865a\u5f15\u7528\uff0c\u5c31\u4f1a\u5728\u56de\u6536\u5bf9\u8c61\u7684\u5185\u5b58\u4e4b\u524d\uff0c\u628a\u8fd9\u4e2a\u865a\u5f15\u7528\u52a0\u5165\u5230\u4e0e\u4e4b \u5173\u8054\u7684\u5f15\u7528\u961f\u5217\u4e2d\u3002\n<\/p>\n<pre class=\"brush:java;\">\r\nReferenceQueue queue = new ReferenceQueue ();\r\nPhantomReference pr = new PhantomReference (object, queue); <\/pre>\n<h2>\n\t\u5f15\u7528\u961f\u5217<br \/>\n<\/h2>\n<p>\n\t\u5f15\u7528\u53ef\u4ee5\u548c\u4e00\u4e2a\u5f15\u7528\u961f\u5217\uff08ReferenceQueue\uff09\u8054\u5408\u4f7f\u7528\uff0c\u5982\u679c\u5f31\u5f15\u7528\u6240\u5f15\u7528\u7684\u5bf9\u8c61\u88ab\u5783\u573e\u56de\u6536\uff0cJava\u865a\u62df\u673a\u5c31\u4f1a\u628a\u8fd9\u4e2a\u5f31\u5f15\u7528\u52a0\u5165\u5230\u4e0e\u4e4b\u5173\u8054\u7684\u5f15\u7528\u961f\u5217\u4e2d\u3002\n<\/p>\n<pre class=\"brush:java;\">\r\nReferenceQueue queue = new ReferenceQueue();\r\nSoftReference ref = new SoftReference(aMyObject, queue); <\/pre>\n<p>\n\t\u90a3\u4e48\u5f53\u8fd9\u4e2aSoftReference\u6240\u8f6f\u5f15\u7528\u7684aMyOhject\u88ab\u5783\u573e\u6536\u96c6\u5668\u56de\u6536\u7684\u540c\u65f6\uff0cref\u6240\u5f3a\u5f15\u7528\u7684SoftReference\u5bf9\u8c61\u88ab\u5217\u5165ReferenceQueue\u3002\u4e5f\u5c31\u662f\u8bf4\uff0cReferenceQueue\u4e2d\u4fdd\u5b58\u7684\u5bf9\u8c61\u662fReference\u5bf9\u8c61\uff0c\u800c\u4e14\u662f\u5df2\u7ecf\u5931\u53bb\u4e86\u5b83\u6240\u8f6f\u5f15\u7528\u7684\u5bf9\u8c61\u7684Reference\u5bf9\u8c61\u3002\u53e6\u5916\u4eceReferenceQueue\u8fd9\u4e2a\u540d\u5b57\u4e5f\u53ef\u4ee5\u770b\u51fa\uff0c\u5b83\u662f\u4e00\u4e2a\u961f\u5217\uff0c\u5f53\u6211\u4eec\u8c03\u7528\u5b83\u7684poll()\u65b9\u6cd5\u7684\u65f6\u5019\uff0c\u5982\u679c\u8fd9\u4e2a\u961f\u5217\u4e2d\u4e0d\u662f\u7a7a\u961f\u5217\uff0c\u90a3\u4e48\u5c06\u8fd4\u56de\u961f\u5217\u524d\u9762\u7684\u90a3\u4e2aReference\u5bf9\u8c61\u3002<br \/>\n\t\u5728\u4efb\u4f55\u65f6\u5019\uff0c\u6211\u4eec\u90fd\u53ef\u4ee5\u8c03\u7528ReferenceQueue\u7684poll()\u65b9\u6cd5\u6765\u68c0\u67e5\u662f\u5426\u6709\u5b83\u6240\u5173\u5fc3\u7684\u975e\u5f3a\u53ef\u53ca\u5bf9\u8c61\u88ab\u56de\u6536\u3002\u5982\u679c\u961f\u5217\u4e3a\u7a7a\uff0c\u5c06\u8fd4\u56de\u4e00\u4e2anull,\u5426\u5219\u8be5\u65b9\u6cd5\u8fd4\u56de\u961f\u5217\u4e2d\u524d\u9762\u7684\u4e00\u4e2aReference\u5bf9\u8c61\u3002\u5229\u7528\u8fd9\u4e2a\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u68c0\u67e5\u54ea\u4e2aSoftReference\u6240\u8f6f\u5f15\u7528\u7684\u5bf9\u8c61\u5df2\u7ecf\u88ab\u56de\u6536\u3002\u4e8e\u662f\u6211\u4eec\u53ef\u4ee5\u628a\u8fd9\u4e9b\u5931\u53bb\u6240\u8f6f\u5f15\u7528\u7684\u5bf9\u8c61\u7684SoftReference\u5bf9\u8c61\u6e05\u9664\u6389\u3002\u5e38\u7528\u7684\u65b9\u5f0f\u4e3a:\n<\/p>\n<pre class=\"brush:java;\">\r\nSoftReference ref = null;\r\nwhile ((ref = (EmployeeRef) q.poll()) != null) {\r\n\/\/ \u6e05\u9664ref\r\n}\r\n<\/pre>\n<!-- <audio autoplay=\"autoplay\" height=\"100\" width=\"100\" hidden=\"true\"><source src=\"https:\/\/c.coka.la\/orAvPR.mp3\" type=\"audio\/mp3\"\/><\/audio><img decoding=\"async\" src=\"https:\/\/images.weserv.nl\/?url=https:\/\/ws3.sinaimg.cn\/large\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/> --><p><!-- <img decoding=\"async\" src=\"https:\/\/raw.githubusercontent.com\/xmt1139057136\/xttblog\/master\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/>--><img decoding=\"async\" src=\"https:\/\/saas.51autoparts.cn\/api\/admin\/sys-file\/oss\/file?fileName=84db51f8561e448f9a4fda2eff0811f9.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/><\/p><p>\u6700\u540e\uff0c\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u4e2a\u4eba\u5fae\u4fe1\u516c\u4f17\u53f7\uff1a\u4e1a\u4f59\u8349\uff08yyucao\uff09\uff01<b>\u53ef\u52a0\u4f5c\u8005\u5fae\u4fe1\u53f7\uff1a<font color=\"red\">xttblog2<\/font>\u3002\u5907\u6ce8\uff1a\u201c1\u201d\uff0c\u6dfb\u52a0\u535a\u4e3b\u5fae\u4fe1\u62c9\u4f60\u8fdb\u5fae\u4fe1\u7fa4\u3002\u5907\u6ce8\u9519\u8bef\u4e0d\u4f1a\u540c\u610f\u597d\u53cb\u7533\u8bf7\u3002<\/b>\u518d\u6b21\u611f\u8c22\u60a8\u7684\u5173\u6ce8\uff01\u540e\u7eed\u6709\u7cbe\u5f69\u5185\u5bb9\u4f1a\u7b2c\u4e00\u65f6\u95f4\u53d1\u7ed9\u60a8\uff01\u539f\u521b\u6587\u7ae0\u6295\u7a3f\u8bf7\u53d1\u9001\u81f3532009913@qq.com\u90ae\u7bb1\u3002\u5546\u52a1\u5408\u4f5c\u4e5f\u53ef\u6dfb\u52a0\u4f5c\u8005\u5fae\u4fe1\u8fdb\u884c\u8054\u7cfb\uff01<\/p><p>\u672c\u6587\u539f\u6587\u51fa\u5904\uff1a<a href=\"https:\/\/www.xttblog.com\">\u4e1a\u4f59\u8349<\/a>\uff1a &raquo; <a href=\"https:\/\/www.xttblog.com\/?p=2734\">JAVA\u4e2d\u56db\u79cd\u5f15\u7528\uff0c\u5f3a\u5f15\u7528\uff0c\u8f6f\u5f15\u7528\uff0c\u5f31\u5f15\u7528\uff0c\u865a\u5f15\u7528\u6559\u7a0b<\/a><\/p><!-- <div class=\"bd-reward-stl\"><button id=\"bdRewardBtn\"><span><\/span><\/button><\/div> -->","protected":false},"excerpt":{"rendered":"<p>Java \u4e2d\u5171\u6709\u56db\u79cd\u5f15\u7528\u3002\u5305\u62ec\u5f3a\u5f15\u7528\uff0c\u8f6f\u5f15\u7528\uff0c\u5f31\u5f15\u7528\uff0c\u865a\u5f15\u7528\u3002\u672c\u6587\u5c06\u5206\u522b\u4ecb\u7ecd\u5b83\u4eec\u3002 \u5f3a\u5f15\u7528 \u5f3a\u5f15\u7528\uff08Stron [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[69,1042,1093,1104,142],"class_list":["post-2734","post","type-post","status-publish","format-standard","hentry","category-java","tag-java","tag-ip","tag-1093","tag-1104","tag-142"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2734","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=2734"}],"version-history":[{"count":1,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2734\/revisions"}],"predecessor-version":[{"id":2735,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2734\/revisions\/2735"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2734"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2734"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2734"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}