{"id":1156,"date":"2024-07-20T11:54:55","date_gmt":"2024-07-20T03:54:55","guid":{"rendered":"http:\/\/www.spiceandwolf.com.cn\/?p=1156"},"modified":"2024-10-10T12:14:05","modified_gmt":"2024-10-10T04:14:05","slug":"jvm-running-data-area","status":"publish","type":"post","link":"http:\/\/www.spiceandwolf.com.cn\/index.php\/jvm-running-data-area\/","title":{"rendered":"\u8fd0\u884c\u65f6\u6570\u636e\u533a"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">\u8fd0\u884c\u65f6\u6570\u636e\u533a\u6982\u8ff0<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"591\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-10-1024x591.png\" alt=\"\" class=\"wp-image-1157\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-10-1024x591.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-10-300x173.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-10-768x443.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-10-1536x886.png 1536w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-10-2048x1181.png 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">JVM\u8fd0\u884c\u65f6\u6570\u636e\u533a\u89c4\u8303<\/h4>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"579\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-11-1024x579.png\" alt=\"\" class=\"wp-image-1159\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-11-1024x579.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-11-300x170.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-11-768x434.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-11-1536x868.png 1536w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-11.png 1752w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">\u5206\u914dJVM\u5185\u5b58\u7a7a\u95f4<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5206\u914d\u5806\u7684\u5927\u5c0f<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-Xms\uff08\u5806\u7684\u521d\u59cb\u5bb9\u91cf\uff09\n-Xmx\uff08\u5806\u7684\u6700\u5927\u5bb9\u91cf\uff09\n\n-XX:InitialHeapSize=268435456\n-XX:MaxHeapSize=4294967296\n\n# \u5982\u679c\u4e3a\u4e86\u63d0\u9ad8\u6027\u80fd\uff0c\u53ef\u4ee5\u8003\u8651\u53bb\u6d6a\u8d39\u7a7a\u95f4\uff0c\u5c31\u662f\u5c06\u521d\u59cb\u5bb9\u91cf\u548c\u6700\u5927\u5bb9\u91cf\u76f8\u7b49<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5206\u914d\u65b9\u6cd5\u533a\u7684\u5927\u5c0f<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-XX:PermSize\n   \u6c38\u4e45\u4ee3\u7684\u521d\u59cb\u5bb9\u91cf\n-XX:MaxPermSize\n   \u6c38\u4e45\u4ee3\u7684\u6700\u5927\u5bb9\u91cf\n\n-XX:MetaspaceSize\n   \u5143\u7a7a\u95f4\u7684\u521d\u59cb\u5927\u5c0f\uff0c\u8fbe\u5230\u8be5\u503c\u5c31\u4f1a\u89e6\u53d1\u5783\u573e\u6536\u96c6\u8fdb\u884c\u7c7b\u578b\u5199\u5728\uff0c\u901a\u8bc6GC\u4f1a\u5806\u8be5\u503c\u8fdb\u884c\u8c03\u6574\uff1b\u5982\u679c\u91ca\u653e\u4e86\u5927\u91cf\u7684\u7a7a\u95f4\uff0c\u5c31\u9002\u5f53\u964d\u4f4e\u8be5\u503c\uff1b\u5982\u679c\u91ca\u653e\u4e86\u5f88\u5c11\u7684\u7a7a\u95f4\uff0c\u90a3\u4e48\u5728\u4e0d\u8d85\u8fc7MaxMetaspaceSize\u65f6\uff0c\u9002\u5f53\u63d0\u9ad8\u8be5\u503c\u3002\n-XX:MaxMetaspaceSize\n   \u6700\u5927\u7a7a\u95f4\uff0c\u9ed8\u8ba4\u65f6\u6ca1\u6709\u9650\u5236\u7684\n\n-XX:MinMetaspaceFreeRatio\n   \u5728GC\u4e4b\u540e\uff0c\u6700\u5c0f\u7684metaspace\u5269\u4f59\u7a7a\u95f4\u5bb9\u91cf\u7684\u767e\u5206\u6bd4\uff0c\u51cf\u5c11\u4e3a\u5206\u914d\u7a7a\u95f4\u6240\u5bfc\u81f4\u7684\u5783\u573e\u56de\u6536\n-XX:MaxMetaspaceFreeRatio\n   \u5728GC\u4e4b\u540e\uff0c\u6700\u5927\u7684metaspace\u5269\u4f59\u7a7a\u95f4\u5bb9\u91cf\u7684\u767e\u5206\u6bd4\uff0c\u51cf\u5c11\u4e3a\u5206\u914d\u7a7a\u95f4\u6240\u5bfc\u81f4\u7684\u5783\u573e\u56de\u6536<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5206\u914d\u7ebf\u7a0b\u7a7a\u95f4\u7684\u5927\u5c0f<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-Xss:\n   \u4e3ajvm\u542f\u52a8\u7684\u6bcf\u4e2a\u7ebf\u7a0b\u5206\u914d\u7684\u5185\u5b58\u5927\u5c0f\uff0cjdk1.4\u9ed8\u8ba4256K\uff0cjdk1.5+\u9ed8\u8ba41M<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">\u65b9\u6cd5\u533a<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">\u65b9\u6cd5\u533a\u5b58\u50a8\u4ec0\u4e48\u6570\u636e<\/h4>\n\n\n\n<p>\u7c7b\u578b\u4fe1\u606f\u3001\u65b9\u6cd5\u4fe1\u606f\u3001\u5b57\u6bb5\u4fe1\u606f\u3001Code\u533a\u3001\u65b9\u6cd5\u8868\u3001\u9759\u6001\u53d8\u91cf\uff081.7\u540e\u5b58\u5728\u5806\u4e2d\uff09\u3001\u8fd0\u884c\u65f6\u5e38\u91cf\u6c60\uff081.7\u540e\u5b58\u5728\u5806\u4e2d\uff09\u3001JIT\u7f16\u8bd1\u4e4b\u540e\u7684\u4ee3\u7801\u7f13\u5b58\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u6c38\u4e45\u4ee3\u548c\u5143\u7a7a\u95f4\u7684\u533a\u522b\u662f\u4ec0\u4e48<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>jdk1.8\u4e4b\u524d\u4f7f\u7528\u7684\u65b9\u6cd5\u533a\u5b9e\u73b0\u662f\u6c38\u4e45\u4ee3\uff0cjdk1.8\u4e4b\u540e\u65b9\u6cd5\u533a\u5b9e\u73b0\u662f\u5143\u7a7a\u95f4\u3002<\/li>\n\n\n\n<li>\u5b58\u50a8\u4f4d\u7f6e\u4e0d\u540c\uff0c\u6c38\u4e45\u4ee3\u6240\u4f7f\u7528\u7684\u5185\u5b58\u533a\u57df\u662fJVM\u8fdb\u7a0b\u6240\u4f7f\u7528\u7684\u533a\u57df\uff0c\u5b83\u7684\u5927\u5c0f\u53d7\u6574\u4e2aJVM\u7684\u5927\u5c0f\u6240\u9650\u5236\u3002\u5143\u7a7a\u95f4\u6240\u4f7f\u7528\u7684\u5185\u5b58\u533a\u57df\u662f\u7269\u7406\u5185\u5b58\u533a\u57df\uff0c\u53ea\u4f1a\u53d7\u5230\u7269\u7406\u5185\u5b58\u5927\u5c0f\u7684\u9650\u5236\u3002<\/li>\n\n\n\n<li>\u5b58\u50a8\u5185\u5bb9\u4e0d\u540c\uff0c\u6c38\u4e45\u4ee3\u5b58\u50a8\u7684\u4fe1\u606f\u57fa\u672c\u4e0a\u5c31\u662f\u4e0a\u9762\u65b9\u6cd5\u533a\u5b58\u50a8\u5185\u5bb9\u3002\u5143\u7a7a\u95f4\u53ea\u5b58\u50a8\u7c7b\u7684\u5143\u4fe1\u606f\uff0c\u800c\u9759\u6001\u53d8\u91cf\u548c\u8fd0\u884c\u65f6\u5e38\u91cf\u6c60\u90fd\u632a\u5230\u5806\u4e2d\u5b58\u50a8\u3002<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u4e3a\u4ec0\u4e48\u8981\u4f7f\u7528\u5143\u7a7a\u95f4\u6765\u66ff\u6362\u6c38\u4e45\u4ee3\uff1f<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5b57\u7b26\u4e32\u5b58\u5728\u6c38\u4e45\u4ee3\u4e2d\uff0c\u5bb9\u6613\u51fa\u73b0\u6027\u80fd\u95ee\u9898\u548c\u6c38\u4e45\u4ee3\u5185\u5b58\u6ea2\u51fa\u3002<\/li>\n\n\n\n<li>\u7c7b\u53ca\u65b9\u6cd5\u7684\u4fe1\u606f\u7b49\u6bd4\u8f83\u96be\u786e\u5b9a\u5176\u5927\u5c0f\uff0c\u56e0\u6b64\u5bf9\u4e8e\u6c38\u4e45\u4ee3\u7684\u5927\u5c0f\u6307\u5b9a\u6bd4\u8f83\u56f0\u96be\uff0c\u592a\u5c0f\u5bb9\u6613\u51fa\u73b0\u6c38\u4e45\u4ee3\u6ea2\u51fa\uff0c\u592a\u5927\u5219\u5bb9\u6613\u5bfc\u81f4\u8001\u5e74\u4ee3\u6ea2\u51fa\u3002<\/li>\n\n\n\n<li>\u6c38\u4e45\u4ee3\u4f1aGC\u5e26\u6765\u4e0d\u5fc5\u8981\u7684\u590d\u6742\u5ea6\uff0c\u5e76\u4e14\u56de\u6536\u6548\u7387\u4f4e\u3002<\/li>\n\n\n\n<li>Oracle\u8ba1\u5212\u5c06HotSpot\u4e0eJRockit\u5408\u4e8c\u4e3a\u4e00\u3002<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u65b9\u6cd5\u5f02\u5e38\u6f14\u793a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u7c7b\u52a0\u8f7d\u5bfc\u81f4OOM\u5f02\u5e38<\/li>\n\n\n\n<li>\u5b57\u7b26\u4e32OOM\u5f02\u5e38<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u6982\u8ff0<\/h4>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"522\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-13-1024x522.png\" alt=\"\" class=\"wp-image-1165\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-13-1024x522.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-13-300x153.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-13-768x392.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-13-1536x784.png 1536w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-13-2048x1045.png 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u5b58\u50a8<\/h4>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"475\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-12-23.36.06-1024x475.png\" alt=\"\" class=\"wp-image-1164\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-12-23.36.06-1024x475.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-12-23.36.06-300x139.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-12-23.36.06-768x356.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-12-23.36.06-1536x712.png 1536w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-12-23.36.06-2048x949.png 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u6848\u4f8b<\/h4>\n\n\n\n<h5 class=\"wp-block-heading\">\u53cc\u5f15\u53f7\u521b\u5efa<\/h5>\n\n\n\n<pre class=\"wp-block-code\"><code>String str1 = \"abc\";\nString str2 = \"abc\";\nSystem.out.println(str1 == str2);<\/code><\/pre>\n\n\n\n<p>\u53cc\u5f15\u53f7\u5f62\u5f0f\u521b\u5efa\u5b57\u7b26\u4e32\u65f6\uff0cJVM\u4f1a\u5148\u53bb\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u6839\u636eStringTable\u67e5\u627e\u6709\u6ca1\u6709\u5bf9\u5e94\u7684\u5b57\u7b26\u4e32\uff0c\u6709\u5219\u8fd4\u56de\u5f15\u7528\uff0c\u6ca1\u6709\u5219\u5728\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u521b\u5efa\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u5e76\u5728StringTable\u4e2d\u589e\u52a0\u4e00\u7ec4key-value\u5bf9\uff0c\u5e76\u8fd4\u56de\u5f15\u7528\u3002\u672c\u4f8b\u4e2d\uff0cstr1\u521d\u59cb\u5316\u65f6\u4f1a\u5728StringTable\u4e2d\u589e\u52a0\u4e00\u7ec4&#8221;abc&#8221;\u7684key-value\u5bf9\uff0c\u7136\u540e\u8fd4\u56de\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u7684\u5bf9\u8c61\u5f15\u7528\uff0cstr2\u521d\u59cb\u5316\u65f6\u4f1a\u5728StringTable\u4e2d\u627e\u5230\u5339\u914d\u9879\uff0c\u76f4\u63a5\u8fd4\u56de\u5f15\u7528\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">new\u521b\u5efa<\/h5>\n\n\n\n<pre class=\"wp-block-code\"><code>String str1 = \"abc\";\nString str2 = new String(\"abc\");\nString str3 = new String(\"abc\");\nSystem.out.println(str1 == str2);\nSystem.out.println(str2 == str3);<\/code><\/pre>\n\n\n\n<p>new\u5f62\u5f0f\u521b\u5efa\u5b57\u7b26\u4e32\u65f6\uff0cJVM\u4f1a\u5148\u53bb\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u6839\u636eStringTable\u67e5\u627e\u6709\u6ca1\u6709\u5bf9\u5e94\u7684\u5b57\u7b26\u4e32\uff0c\u6709\u5219\u5728\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u5916\u5806\u5185\u521b\u5efa\u4e00\u4e2a\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u5e76\u8fd4\u56de\u8fd9\u4e2a\u5806\u5185\u5b57\u7b26\u4e32\u5bf9\u8c61\u7684\u5f15\u7528\uff1b\u6ca1\u6709\u5219\u5728\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u521b\u5efa\u5b57\u7b26\u4e32\u5bf9\u8c61\u5e76\u589e\u52a0\u5bf9\u5e94StringTable\u9879\u540e\uff0c\u518d\u5728\u5806\u5185\u521b\u5efa\u4e00\u4e2a\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u5e76\u8fd4\u56de\u8fd9\u4e2a\u5806\u5185\u5b57\u7b26\u4e32\u5bf9\u8c61\u7684\u5f15\u7528\u3002\u672c\u4f8b\u4e2d\uff0cstr1\u5f15\u7528\u6307\u5411\u7684\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u800cstr2\u5f15\u7528\u6307\u5411\u7684\u5806\u5185\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u6240\u4ee5\u7b2c\u4e00\u4e2a\u7ed3\u679c\u662ffalse\uff0c\u800cstr2\u548cstr3\u5728\u5806\u5185\u6307\u5411\u4e0d\u540c\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u6240\u4ee5\u7b2c\u4e8c\u4e2a\u7ed3\u679c\u4e5f\u662ffalse\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u7f16\u8bd1\u4f18\u5316<\/h5>\n\n\n\n<pre class=\"wp-block-code\"><code>String str1 = \"a\" + \"b\";  \/\/ \u7f16\u8bd1\u4f18\u5316\u540e\u76f8\u5f53\u4e8e String str1 = \"ab\";\nfinal String s = \"a\"; \/\/ \u5e38\u91cfa\nString str2 = s + \"b\"; \/\/ s\u662f\u5e38\u91cf\uff0c\u5728\u7f16\u8bd1\u4f18\u5316\u540e\u76f8\u5f53\u4e8e String str2 = \"ab\";\nSystem.out.println(str1 == \"ab\");\nSystem.out.println(str2 == \"ab\");<\/code><\/pre>\n\n\n\n<p>\u4e24\u79cd\u60c5\u51b5\u90fd\u4f1a\u8fdb\u884c\u7f16\u8bd1\u4f18\u5316\uff0c\u7ed3\u679c\u90fd\u662ftrue\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u65b9\u6cd5\u521b\u5efa<\/h5>\n\n\n\n<pre class=\"wp-block-code\"><code>String str7 = \"abc\".substring(0, 2); \/\/ \u76f8\u5f53\u4e8enew String(\"ab\")\nSystem.out.println(str7 == \"ab\");\n\nString str8 = \"abc\".toUpperCase(); \/\/ \u76f8\u5f53\u4e8enew String(\"ABC\")\nSystem.out.println(str8 == \"ABC\");<\/code><\/pre>\n\n\n\n<p>\u7ed3\u679c\u90fd\u4e3afalse\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">String\u5bf9\u8c61\u7684intern()\u65b9\u6cd5<\/h4>\n\n\n\n<h5 class=\"wp-block-heading\">\u4f5c\u7528<\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u8fd4\u56destringtable\u4e2d\u5bf9\u5e94\u5b57\u7b26\u4e32\u5bf9\u8c61\u7684\u5f15\u7528\u503c<\/li>\n\n\n\n<li>\u5982\u679cstringtable\u4e2d\u6ca1\u6709\u5bf9\u5e94\u5b57\u7b26\u4e32\u5bf9\u8c61\u8bb0\u5f55\uff0c\u5219\u52a8\u6001\u6dfb\u52a0\u5b57\u7b26\u4e32\u5bf9\u8c61\u5230stringtable\u4e2d<\/li>\n\n\n\n<li>\uff08jdk1.7\u4e4b\u524d\uff09\u5982\u679cstringtable\u4e2d\u6ca1\u6709\u5bf9\u5e94\u5b57\u7b26\u4e32\u5bf9\u8c61\u8bb0\u5f55\uff0c\u6b64\u65f6\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u6ca1\u6709\u5bf9\u5e94\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u5806\u4e2d\u6709\u5bf9\u5e94\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u5219\u4f1a\u5c06\u5806\u4e2d\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\u590d\u5236\u5230\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\uff0c\u5e76\u57fa\u4e8e\u590d\u5236\u7684\u5bf9\u8c61\u6dfb\u52a0stringtable\u9879\u3002<\/li>\n<\/ul>\n\n\n\n<h5 class=\"wp-block-heading\">\u6848\u4f8b<\/h5>\n\n\n\n<pre class=\"wp-block-code\"><code>        \/\/ c\u6307\u5411\u7684\u662f\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u7684world\u5b57\u7b26\u4e32\u5bf9\u8c61\u5730\u5740\uff0c\n        \/\/ \u800cc.intern()\u53d6\u5f97strintable\u8868\u4e2d\u7684\u5f15\u7528\u5730\u5740\u4e5f\u662f\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\u5730\u5740\uff0c\n        \/\/ \u6240\u4ee5\u4e3atrue\n        String c = \"world\";\n        System.out.println(c.intern() == c); \/\/ true\n\n        \/\/ d\u521b\u5efa\u65f6\uff0c\u4f1a\u540c\u65f6\u5728\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u548c\u5806\u4e2d\u521b\u5efamike\u5b57\u7b26\u4e32\u5bf9\u8c61\uff0c\u800cd\u6307\u5411\u7684\u5219\u662f\u5806\u4e2d\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\u5730\u5740\uff0c\n        \/\/ \u800cd.intern()\u4f1a\u5728stringtable\u4e2d\u67e5\u627e\u5339\u914d\u9879\uff0c\u800cstringtable\u4e2d\u5339\u914d\u9879\u7684\u5f15\u7528\u5730\u5740\u5219\u662f\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\u5730\u5740\uff0c\n        \/\/ \u6240\u4ee5\u4e3afalse\n        String d = new String(\"mike\");\n        System.out.println(d.intern() == d); \/\/ false\n\n        \/\/ e\u521b\u5efa\u65f6\uff0c\u56e0\u4e3a\u6ca1\u6709john\u5e38\u91cf\uff0c\u6240\u4ee5\u7f16\u8bd1\u671f\u95f4\u4e0d\u4f1a\u5c06john\u52a0\u5165\u5230\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\uff0c\u6240\u4ee5\u5728\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u4e2d\u6ca1\u6709john\u5bf9\u8c61\n        \/\/ \u800c\u8fd0\u884c\u671f\u95f4\u4f1a\u5728\u5806\u4e2d\u521b\u5efajohn\u5b57\u7b26\u4e32\u5bf9\u8c61\n        \/\/ \u8fd9\u65f6stringtable\u4e2d\u6ca1\u6709john\u5bf9\u5e94\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\u8bb0\u5f55\uff0c\u6240\u4ee5e.intern()\u4f1a\u5728\u628a\u5806\u4e2d\u7684john\u5b57\u7b26\u4e32\u5bf9\u8c61\u52a0\u5165\u6dfb\u52a0\u5230stringtable\u4e2d\n        \/\/ \u6240\u4ee5\u7ed3\u679c\u4e3atrue\n        String e = new String(\"jo\") + new String(\"hn\");\n        System.out.println(e.intern() == e); \/\/ true\n\n        \/\/ \u56e0\u4e3ajava\u4e3a\u7279\u6b8a\u5b57\u7b26\uff0c\u6240\u4ee5\u5728\u7a0b\u5e8f\u8fd0\u884c\u521d\uff0cjava\u5c31\u88ab\u52a0\u8f7d\u5230stringtable\u4e2d\u4e86\n        \/\/ \u6240\u4ee5\u8fd9\u91cc\u662ffalse\n        String f = new String(\"ja\") + new String(\"va\");\n        System.out.println(f.intern() == f); \/\/ false<\/code><\/pre>\n\n\n\n<p>jdk1.7\u548cjdk1.7\u4e4b\u524dintern()\u65b9\u6cd5\u5dee\u522b<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>        \/\/ jdk1.6\u7ed3\u679c\u662ffalse\uff0cjdk1.7\u7ed3\u679c\u662ftrue\n        String s3 = new String(\"l\") + new String(\"l\");\n        s3.intern();\n        String s4 = \"ll\";\n        System.out.println(s3 == s4);<\/code><\/pre>\n\n\n\n<h5 class=\"wp-block-heading\">\u4f7f\u7528\u573a\u666f<\/h5>\n\n\n\n<pre class=\"wp-block-code\"><code>public class StringPoolTest2 {\n    static final int MAX = 1000 * 10000;\n    static final String&#91;] arr = new String&#91;MAX];\n\n    public static void main(String&#91;] args) throws IOException {\n        Integer&#91;] DB_DATA = new Integer&#91;10];\n        Random random = new Random(10 * 10000);\n        for (int i = 0; i &lt; DB_DATA.length; i++) {\n            DB_DATA&#91;i] = random.nextInt();\n            System.out.println(DB_DATA);\n        }\n\n        for (int i = 0; i &lt; MAX; i++) {\n            \/\/ \u4f7f\u7528intern()\u540e\uff0c\u5806\u4e2d\u521b\u5efa\u7684\u5b57\u7b26\u4e32\u5bf9\u8c61\u5b9e\u4f8b\u6570\u53ea\u670910\u4e2a\uff0c\u8282\u7701\u4e86\u5806\u5185\u5b58\u7a7a\u95f4\n            arr&#91;i] = new String(String.valueOf(DB_DATA&#91;i % DB_DATA.length])).intern();\n            \/\/ \u4e0d\u4f7f\u7528intern()\uff0c\u5806\u4e2d\u4f1a\u53cd\u590d\u521b\u5efa1000*10000\u4e2a\u5b57\u7b26\u4e32\u5bf9\u8c61\n\/\/            arr&#91;i] = new String(String.valueOf(DB_DATA&#91;i % DB_DATA.length]));\n        }\n        System.out.println(\"\u7b49\u5f85\u4e2d...\");\n        System.in.read();\n    }\n}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">java\u5806<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">\u5806\u5185\u5b58\u5206\u914d<\/h4>\n\n\n\n<p>JAVA\u5806\u5728JVM\u542f\u52a8\u65f6\u521b\u5efa\uff0c\u662f\u901a\u8fc7<strong><em>\u5783\u573e\u6536\u96c6\u5668<\/em><\/strong>\u53bb\u5b9e\u73b0\u5185\u5b58\u5206\u914d\u7684\u3002\u5b83\u662f\u865a\u62df\u673a\u7ba1\u7406\u7684\u6700\u5927\u7684\u4e00\u5757\u5185\u5b58\u7a7a\u95f4\u3002\u4e5f\u662f\u5783\u573e\u56de\u6536\u7684\u4e3b\u8981\u533a\u57df\uff0c\u800c\u5176\u4e3b\u8981\u91c7\u7528<strong><em>\u5206\u4ee3\u56de\u6536\u7b97\u6cd5<\/em><\/strong>\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"318\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-16-1024x318.png\" alt=\"\" class=\"wp-image-1173\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-16-1024x318.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-16-300x93.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-16-768x239.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-16-1536x477.png 1536w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-16.png 1590w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h5 class=\"wp-block-heading\">\u5806\u7a7a\u95f4\u7684\u53c2\u6570\u8bbe\u7f6e<\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>-XX:+PrintFlagsInitial: \u67e5\u770b\u6240\u6709\u53c2\u6570\u7684\u9ed8\u8ba4\u521d\u59cb\u503c<\/li>\n\n\n\n<li>-XX:+PrintFlagsFinal: \u67e5\u770b\u6700\u7ec8\u503c(\u521d\u59cb\u503c\u53ef\u80fd\u88ab\u4fee\u6539\u6389)<\/li>\n\n\n\n<li>-Xms:\u521d\u59cb\u5806\u7a7a\u95f4\u5185\u5b58(\u9ed8\u8ba4\u4e3a\u7269\u7406\u5185\u5b58\u76841\/64)<\/li>\n\n\n\n<li>-Xmx:\u6700\u5927\u5806\u7a7a\u95f4\u5185\u5b58(\u9ed8\u8ba4\u4e3a\u7269\u7406\u5185\u5b58\u76841\/4)<\/li>\n\n\n\n<li>-Xmn:\u8bbe\u7f6e\u65b0\u751f\u4ee3\u7684\u5927\u5c0f(\u521d\u59cb\u503c\u53ca\u6700\u5927\u503c)<\/li>\n\n\n\n<li>-XX:NewRatio:\u914d\u7f6e\u65b0\u751f\u4ee3\u4e0e\u8001\u5e74\u4ee3\u5728\u5806\u7ed3\u6784\u7684\u5360\u6bd4<\/li>\n\n\n\n<li>-XX:SurvivorRatio:\u8bbe\u7f6e\u65b0\u751f\u4ee3\u4e2dEden\u548cS0\/S1\u7a7a\u95f4\u6bd4\u4f8b<\/li>\n\n\n\n<li>-XX:MaxTenuringThreshold\u8bbe\u7f6e\u65b0\u751f\u4ee3\u5783\u573e\u7684\u6700\u5927\u5e74\u9f84<\/li>\n\n\n\n<li>-XX:+PrintGCDetails:\u8f93\u51fa\u8be6\u7ec6\u7684GC\u5904\u7406\u65e5\u5fd7<\/li>\n\n\n\n<li>-XX:PrintGC -verbose:gc:\u6253\u5370GC\u7b80\u8981\u4fe1\u606f<\/li>\n\n\n\n<li>-XX:HandlePromotionFailure:\u662f\u5426\u8bbe\u7f6e\u7a7a\u95f4\u62c5\u4fdd<\/li>\n<\/ul>\n\n\n\n<h5 class=\"wp-block-heading\">\u901a\u8fc7\u5de5\u5177\u67e5\u770b\u5806\u5185\u5b58\u4fe1\u606f<\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>jvisual vm\u5de5\u5177<\/li>\n\n\n\n<li>&#8211; XX:+PrintGCDetails\u865a\u62df\u673a\u53c2\u6570<\/li>\n\n\n\n<li>jstat\u547d\u4ee4<\/li>\n\n\n\n<li>jmap\u547d\u4ee4<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u5bf9\u8c61\u5185\u5b58\u5206\u914d<\/h4>\n\n\n\n<h5 class=\"wp-block-heading\">\u5bf9\u8c61\u521b\u5efa\u6d41\u7a0b<\/h5>\n\n\n\n<pre class=\"wp-block-code\"><code>Student student = new Student();<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"693\" height=\"1024\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-18-693x1024.png\" alt=\"\" class=\"wp-image-1175\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-18-693x1024.png 693w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-18-203x300.png 203w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-18-768x1134.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-18.png 964w\" sizes=\"auto, (max-width: 693px) 100vw, 693px\" \/><\/figure>\n\n\n\n<h5 class=\"wp-block-heading\">\u5bf9\u8c61\u5185\u5b58\u5206\u914d\u65b9\u5f0f<\/h5>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td>\u5206\u914d\u65b9\u6cd5<\/td><td>\u8bf4\u660e<\/td><td>\u6536\u96c6\u5668<\/td><\/tr><tr><td>\u6307\u9488\u78b0\u649e<\/td><td>\u5185\u5b58\u5730\u5740\u662f\u8fde\u7eed\u7684\uff08\u5e74\u8f7b\u4ee3\uff09<\/td><td>Serial\u548cParNew<\/td><\/tr><tr><td>\u7a7a\u95f2\u5217\u8868<\/td><td>\u5185\u5b58\u5730\u5740\u4e0d\u8fde\u7eed\uff08\u5e74\u8001\u4ee3\uff09<\/td><td>CMS\u548cMark-Sweep<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">\u5185\u5b58\u653e\u914d\u65b9\u5f0f<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"710\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-19-1024x710.png\" alt=\"\" class=\"wp-image-1176\" style=\"width:301px;height:auto\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-19-1024x710.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-19-300x208.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-19-768x532.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-19.png 1324w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h5 class=\"wp-block-heading\">\u5bf9\u8c61\u5185\u5b58\u5206\u914d\u5b89\u5168\u95ee\u9898<\/h5>\n\n\n\n<p>\u95ee\u9898\uff1a\u5728\u5206\u914d\u5185\u5b58\u65f6\uff0cJVM\u865a\u62df\u673a\u7ed9A\u7ebf\u7a0b\u5206\u914d\u8fc7\u7a0b\u4e2d\uff0c\u6307\u9488\u672a\u4fee\u6539\u524d\uff0c\u7ebf\u7a0bB\u53ef\u80fd\u62ff\u5230\u540c\u4e00\u5757\u5185\u5b58\u7a7a\u95f4\uff0c\u5bfc\u81f4\u5199\u5165\u95ee\u9898\u3002<\/p>\n\n\n\n<p>\u89e3\u51b3\u65b9\u6cd5\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u865a\u62df\u673a\u91c7\u7528CAS\uff08\u4e50\u89c2\u9501\uff09\u548c\u5931\u8d25\u91cd\u8bd5\u7684\u65b9\u5f0f\u4fdd\u8bc1\u66f4\u65b0\u64cd\u4f5c\u7684\u539f\u5b50\u6027\u3002<\/li>\n\n\n\n<li>TLAB\u672c\u5730\u7ebf\u7a0b\u5206\u914d\u7f13\u51b2\u3002\u4e3a\u6bcf\u4e00\u4e2a\u7ebf\u7a0b\u9884\u5148\u5206\u914d\u4e00\u5757\u5185\u5b58\u3002<\/li>\n<\/ul>\n\n\n\n<p>JVM\u5728\u7b2c\u4e00\u6b21\u7ed9\u7ebf\u7a0b\u4e2d\u7684\u5bf9\u8c61\u5206\u914d\u5185\u5b58\u65f6\uff0c\u9996\u5148\u4f7f\u7528CAS\u8fdb\u884cTLAB\u7684\u5206\u914d\u3002\u5f53\u5bf9\u8c61\u5927\u4e8eTLAB\u4e2d\u7684\u5269\u4f59\u5185\u5b58\u6216TLAB\u7684\u5185\u5b58\u5df2\u7528\u5c3d\u65f6\uff0c\u518d\u91c7\u7528\u4e0a\u8ff0\u7684CAS\u8fdb\u884c\u5185\u5b58\u5206\u914d\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u5bf9\u8c61\u5206\u914d\uff08\u5185\u5b58\u7a7a\u95f4\uff09\u8fc7\u7a0b<\/h5>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"512\" height=\"1024\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-21-512x1024.png\" alt=\"\" class=\"wp-image-1178\" style=\"width:363px;height:auto\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-21-512x1024.png 512w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-21-150x300.png 150w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-21.png 672w\" sizes=\"auto, (max-width: 512px) 100vw, 512px\" \/><\/figure>\n\n\n\n<h5 class=\"wp-block-heading\">\u8fdb\u5165\uff08\u664b\u5347\uff09\u8001\u5e74\u4ee3\u7684\u6761\u4ef6<\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5b58\u6d3b\u5e74\u9f84\u592a\u5927\uff0c\u9ed8\u8ba4\u5927\u4e8e15\u6b21\uff08-XX:MaxTenuringThreshold\uff09<\/li>\n\n\n\n<li>\u52a8\u6001\u5e74\u9f84\u5224\u65ad\u3002MinorGC\u540eSurvivor\u533a\u57df\u4e2d\u4e00\u6279\u5bf9\u8c61\u7684\u603b\u5927\u5c0f\u5927\u4e8e\u8fd9\u5757Survivor\u533a\u57df\u5185\u5b58\u5927\u5c0f\u768450%\uff08-XX:TargetSurvivorRatio\uff09\uff0c\u90a3\u4e48\u6b64\u65f6\u5927\u4e8e\u7b49\u4e8e\u8fd9\u6279\u5bf9\u8c61\u5e74\u9f84\u6700\u5927\u503c\u7684\u5bf9\u8c61\uff0c\u5c31\u53ef\u4ee5\u76f4\u63a5\u8fdb\u5165\u8001\u5e74\u4ee3\u3002<\/li>\n\n\n\n<li>\u5927\u5bf9\u8c61\u76f4\u63a5\u8fdb\u5165\u8001\u5e74\u4ee3\u3002\u524d\u63d0\u662fSerial\u548cParNew\u6536\u96c6\u5668\u3002<\/li>\n\n\n\n<li>MinorGC\u540e\u5b58\u6d3b\u5bf9\u8c61\u592a\u591a\u65e0\u6cd5\u653e\u5165Survivor\u533a\u3002<\/li>\n\n\n\n<li>\u7a7a\u95f4\u62c5\u4fdd\u673a\u5236\u3002\n<ul class=\"wp-block-list\">\n<li>jdk1.6\u4e4b\u524d\u9700\u8981\u901a\u8fc7-XX:-HandlePromotionFailure\u8bbe\u7f6e\u624d\u80fd\u8d77\u4f5c\u7528\uff081.6\u4e4b\u540e\u5e9f\u5f03\uff09\u3002\u53ea\u9700\u8981\u5224\u65ad\u8001\u5e74\u4ee3\u53ef\u7528\u7a7a\u95f4&gt;\u65b0\u751f\u4ee3GC\u4e4b\u540e\u5bf9\u8c61\u603b\u548c\uff0c\u6216\u8005\u8001\u5e74\u4ee3\u53ef\u7528\u7a7a\u95f4&gt;\u5386\u6b21MinorGC\u5347\u5165\u8001\u5e74\u4ee3\u5bf9\u8c61\u7684\u5e73\u5747\u5927\u5c0f\u3002<\/li>\n\n\n\n<li>\u5728MinorGC\u4e4b\u524d\uff0c\u5224\u65ad\u8001\u5e74\u4ee3\u53ef\u7528\u5185\u5b58\u662f\u5426\u5df2\u7ecf\u5c0f\u4e8e\u65b0\u751f\u4ee3\u5168\u90e8\u5bf9\u8c61\u5927\u5c0f\uff0c\u5982\u679c\u5c0f\u4e8e\uff0c\u7ee7\u7eed\u5224\u65ad\uff0c\u8001\u5e74\u4ee3\u5927\u5c0f\u662f\u5426\u5c0f\u4e8e\u5386\u6b21MinorGC\u540e\u8fdb\u5165\u8001\u5e74\u4ee3\u7684\u5bf9\u8c61\u7684\u5e73\u5747\u5927\u5c0f\uff0c\u5982\u679c\u90fd\u6210\u529f\uff0c\u5192\u9669\u8bd5\u4e00\u4e0bMinorGC\u3002\n<ul class=\"wp-block-list\">\n<li>MinorGC\u540e\uff0c\u5269\u4f59\u5b58\u6d3b\u5bf9\u8c61\u5927\u5c0f\u5c0f\u4e8eSurvivor\u5927\u5c0f\uff0c\u76f4\u63a5\u8fdb\u5165Survivor\u533a\u3002<\/li>\n\n\n\n<li>MinorGC\u540e\uff0c\u5269\u4f59\u5b58\u6d3b\u5bf9\u8c61\u5927\u5c0f\u5927\u4e8eSurvivor\u5927\u5c0f\uff0c\u4f46\u5c0f\u4e8e\u8001\u5e74\u4ee3\u5269\u4f59\u5185\u5b58\uff0c\u76f4\u63a5\u8fdb\u5165\u8001\u5e74\u4ee3\u3002<\/li>\n\n\n\n<li>MinorGC\u540e\uff0c\u5269\u4f59\u5b58\u6d3b\u5bf9\u8c61\u5927\u5c0f\u5927\u4e8eSurvivor\u5927\u5c0f\uff0c\u4e5f\u5927\u4e8e\u8001\u5e74\u4ee3\u53ef\u7528\u5185\u5b58\uff0c\u6267\u884c\u4e00\u6b21FGC\u3002FGC\u540e\u4ecd\u6ca1\u6709\u8db3\u591f\u5185\u5b58\u7a7a\u95f4\u5b58\u653eMinorGC\u7684\u5269\u4f59\u5bf9\u8c61\uff0c\u5c31\u4f1aOOM\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"634\" height=\"1024\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-23-634x1024.png\" alt=\"\" class=\"wp-image-1181\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-23-634x1024.png 634w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-23-186x300.png 186w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-23-768x1240.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-23.png 888w\" sizes=\"auto, (max-width: 634px) 100vw, 634px\" \/><figcaption class=\"wp-element-caption\">\u7a7a\u95f4\u62c5\u4fdd\u673a\u5236<\/figcaption><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">\u5bf9\u8c61\u5185\u5b58\u5e03\u5c40<\/h4>\n\n\n\n<p>\u5bf9\u8c61\u5185\u5b58\u5e03\u5c40\u5206\u4e3a\u4e09\u4e2a\u90e8\u5206\uff1a\u5bf9\u8c61\u5934\u3001\u5b9e\u4f8b\u6570\u636e\u548c\u5bf9\u9f50\u586b\u5145\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1222\" height=\"991\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-25-edited-1.png\" alt=\"\" class=\"wp-image-1186\" style=\"width:734px;height:auto\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-25-edited-1.png 1222w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-25-edited-1-300x243.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-25-edited-1-1024x830.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-25-edited-1-768x623.png 768w\" sizes=\"auto, (max-width: 1222px) 100vw, 1222px\" \/><\/figure>\n\n\n\n<p>markword\u7ed3\u6784\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"967\" height=\"500\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-26.png\" alt=\"\" class=\"wp-image-1187\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-26.png 967w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-26-300x155.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-26-768x397.png 768w\" sizes=\"auto, (max-width: 967px) 100vw, 967px\" \/><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">\u5bf9\u8c61\u8bbf\u95ee\u65b9\u5f0f<\/h4>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td>\u65b9\u5f0f<\/td><td>\u4f18\u70b9<\/td><\/tr><tr><td>\u53e5\u67c4<\/td><td>\u7a33\u5b9a\uff0c\u5bf9\u8c61\u88ab\u79fb\u52a8\u53ea\u9700\u8981\u4fee\u6539\u53e5\u67c4\u4e2d\u7684\u5730\u5740<\/td><\/tr><tr><td>\u76f4\u63a5\u6307\u9488<\/td><td>\u8bbf\u95ee\u901f\u5ea6\u5feb\uff0c\u8282\u7701\u4e86\u4e00\u6b21\u6307\u9488\u5b9a\u4f4d\u7684\u5f00\u9500<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">\u5bf9\u8c61\u8bbf\u95ee\u65b9\u5f0f<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">\u76f4\u63a5\u5185\u5b58<\/h2>\n\n\n\n<p>\u76f4\u63a5\u5185\u5b58\u53c8\u53eb\u5806\u5916\u5185\u5b58\uff0c\u5b83\u4e0d\u662fJava\u865a\u62df\u673a\u8fd0\u884c\u65f6\u6570\u636e\u533a\u7684\u4e00\u90e8\u5206\uff0c\u4e5f\u4e0d\u662fJava\u865a\u62df\u673a\u89c4\u8303\u4e2d\u5b9a\u4e49\u7684\u5185\u5b58\u533a\u57df\u3002<\/p>\n\n\n\n<p>\u5728JDK1.4\u4e2d\u65b0\u52a0\u5165\u4e86NIO(New Input\/Output)\u7c7b\uff0c\u5f15\u5165\u4e86\u4e00\u79cd\u57fa\u4e8e\u901a\u9053(channel)\u4e0e\u7f13\u51b2\u533a(buffer)\u7684I\/O\u65b9\u5f0f\uff0c\u5b83\u53ef\u4ee5\u4f7f\u7528native\u51fd\u6570\u76f4\u63a5\u5206\u914d\u5806\u5916\u5185\u5b58\uff0c\u7136\u540e\u901a\u8fc7\u4e00\u4e2a\u5b58\u50a8\u5728Java\u5806\u4e2d\u7684DirectByteBuffer\u5bf9\u8c61\u4f5c\u4e3a\u8fd9\u5757\u5185\u5b58\u7684\u5f15\u7528\u8fdb\u884c\u64cd\u4f5c\u3002\u8fd9\u6837\u80fd\u5728\u4e00\u4e9b\u573a\u666f\u4e2d\u663e\u8457\u63d0\u9ad8\u6027\u80fd\uff0c\u56e0\u4e3a\u907f\u514d\u4e86\u5728Java\u5806\u548cNative\u5806\u4e2d\u6765\u56de\u590d\u5236\u6570\u636e\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u76f4\u63a5\u5185\u5b58\u4e0e\u5806\u5185\u5b58\u6bd4\u8f83<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u76f4\u63a5\u5185\u5b58\u7533\u8bf7\u7a7a\u95f4\u8017\u8d39\u66f4\u9ad8\u7684\u6027\u80fd\uff0c\u5f53\u9891\u7e41\u7533\u8bf7\u5230\u4e00\u5b9a\u91cf\u65f6\u5c24\u4e3a\u660e\u663e\u3002<\/li>\n\n\n\n<li>\u76f4\u63a5\u5185\u5b58IO\u8bfb\u5199\u7684\u6027\u80fd\u8981\u4f18\u4e8e\u666e\u901a\u7684\u5806\u5185\u5b58\uff0c\u5728\u591a\u6b21\u8bfb\u5199\u64cd\u4f5c\u7684\u60c5\u51b5\u4e0b\u5dee\u5f02\u660e\u663e\u3002<\/li>\n\n\n\n<li>\u672c\u673a\u76f4\u63a5\u5185\u5b58\u7684\u5206\u914d\u4e0d\u4f1a\u53d7\u5230Java\u5806\u5927\u5c0f\u7684\u9650\u5236\uff0c\u53d7\u5230\u672c\u673a\u603b\u5185\u5b58\u5927\u5c0f\u9650\u5236\u3002<\/li>\n\n\n\n<li>\u914d\u7f6e\u865a\u62df\u673a\u53c2\u6570\u65f6\uff0c\u4e0d\u8981\u5ffd\u7565\u76f4\u63a5\u5185\u5b58\u9632\u6b62\u51fa\u73b0OutOfMemoryError\u5f02\u5e38\u3002<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u76f4\u63a5\u5185\u5b58\u7684\u5b9e\u73b0<\/h4>\n\n\n\n<p>Java\u4e2d\u5206\u914d\u5806\u5916\u5185\u5b58\u7684\u65b9\u5f0f\u6709\u4e24\u79cd\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u901a\u8fc7ByteBuffer.java#allocationDirect\u5f97\u5230\u4ee5\u4e00\u4e2aDirectByteBuffer\u5bf9\u8c61\u3002<\/li>\n\n\n\n<li>\u76f4\u63a5\u8c03\u7528Unsafe.java#allocationMemory\u5206\u914d\u5185\u5b58\uff0c\u4f46Unsafe\u53ea\u80fd\u5728JDK\u7684\u4ee3\u7801\u4e2d\u8c03\u7528\uff0c\u4e00\u822c\u4e0d\u4f1a\u76f4\u63a5\u4f7f\u7528\u8be5\u65b9\u6cd5\u5206\u914d\u5185\u5b58\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u5176\u4e2dDirectByteBuffer\u4e5f\u662f\u7528Unsafe\u53bb\u5b9e\u73b0\u5185\u5b58\u5206\u914d\u7684\uff0c\u5bf9\u5806\u5185\u5b58\u7684\u5206\u914d\u3001\u8bfb\u5199\u3001\u56de\u6536\u90fd\u505a\u4e86\u5c01\u88c5\u3002<\/p>\n\n\n\n<p>\u6211\u4eec\u4ece\u5806\u5916\u5185\u5b58\u7684\u5206\u914d\u56de\u6536\u3001\u8bfb\u5199\u4e24\u4e2a\u89d2\u5ea6\u53bb\u5206\u6790DirectByteBuffer\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u7a0b\u5e8f\u8ba1\u6570\u5668\uff08PC\u5bc4\u5b58\u5668\uff09<\/h2>\n\n\n\n<p>\u7a0b\u5e8f\u8ba1\u6570\u5668\u7684\u4f5c\u7528\u662f\u5b58\u50a8\u6309\u987a\u5e8f\u6267\u884c\u7684\u4e0b\u4e00\u6761\u6307\u4ee4\u5730\u5740\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u4e8b\u4f8b<\/h4>\n\n\n\n<p>\u6e90\u4ee3\u7801\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public class PCRegisterTest {\n    public static void main(String&#91;] args) {\n        int i = 100;\n        int j = 200;\n        int m = i + j;\n\n        String str = \"a\";\n        System.out.println(m);\n        System.out.println(str);\n    }\n}<\/code><\/pre>\n\n\n\n<p>\u5b57\u8282\u7801\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code> 0 bipush 100\n 2 istore_1\n 3 sipush 200\n 6 istore_2\n 7 iload_1\n 8 iload_2\n 9 iadd\n10 istore_3\n11 ldc #2 &lt;a&gt;\n13 astore 4\n15 getstatic #3 &lt;java\/lang\/System.out : Ljava\/io\/PrintStream;&gt;\n18 iload_3\n19 invokevirtual #4 &lt;java\/io\/PrintStream.println : (I)V&gt;\n22 getstatic #3 &lt;java\/lang\/System.out : Ljava\/io\/PrintStream;&gt;\n25 aload 4\n27 invokevirtual #5 &lt;java\/io\/PrintStream.println : (Ljava\/lang\/String;)V&gt;\n30 return<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"522\" height=\"354\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-29.png\" alt=\"\" class=\"wp-image-1192\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-29.png 522w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-29-300x203.png 300w\" sizes=\"auto, (max-width: 522px) 100vw, 522px\" \/><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">\u7279\u70b9<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5b83\u662f\u4e00\u5757\u5f88\u5c0f\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u51e0\u4e4e\u53ef\u4ee5\u5ffd\u7565\u4e0d\u8ba1\u3002\u4e5f\u662f\u8fd0\u884c\u901f\u5ea6\u6700\u5feb\u7684\u5b58\u50a8\u533a\u57df\u3002<\/li>\n\n\n\n<li>\u5728JVM\u89c4\u8303\u4e2d\uff0c\u6bcf\u4e2a\u7ebf\u7a0b\u90fd\u6709\u5b83\u7684\u7a0b\u5e8f\u8ba1\u6570\u5668\uff0c\u662f\u7ebf\u7a0b\u79c1\u6709\u7684\uff0c\u5b83\u7684\u751f\u547d\u5468\u671f\u4e0e\u7ebf\u7a0b\u7684\u751f\u547d\u5468\u671f\u4fdd\u6301\u4e00\u81f4\u3002<\/li>\n\n\n\n<li>\u4efb\u4f55\u65f6\u95f4\u4e00\u4e2a\u7ebf\u7a0b\u90fd\u6709\u4e00\u4e2a\u65b9\u6cd5\u5728\u6267\u884c\uff0c\u4e5f\u5c31\u662f\u6240\u8c13\u7684\u5f53\u524d\u65b9\u6cd5\u3002\u7a0b\u5e8f\u8ba1\u6570\u5668\u4f1a\u5b58\u50a8\u5f53\u524d\u7ebf\u7a0b\u6b63\u5728\u6267\u884c\u7684java\u65b9\u6cd5JVM\u6307\u4ee4\u5730\u5740\uff1b\u6216\u8005\uff0c\u5982\u679c\u662f\u6267\u884cnative\u65b9\u6cd5\uff0c\u5219\u662f\u672a\u6307\u5b9a\u503c\uff08undefined\uff09\u3002<\/li>\n\n\n\n<li>\u5b83\u662f\u7a0b\u5e8f\u63a7\u5236\u6d41\u7684\u6307\u793a\u5668\uff0c\u5206\u652f\u3001\u5faa\u73af\u3001\u8df3\u8f6c\u3001\u5f02\u5e38\u5904\u7406\u3001\u7ebf\u7a0b\u6062\u590d\u7b49\u57fa\u7840\u529f\u80fd\u90fd\u9700\u8981\u4ee5\u6765\u8fd9\u4e2a\u8ba1\u6570\u5668\u6765\u5b8c\u6210\u3002<\/li>\n\n\n\n<li>\u5b57\u8282\u7801\u89e3\u91ca\u5668\u5de5\u4f5c\u65f6\u5c31\u662f\u901a\u8fc7\u6539\u53d8\u8fd9\u4e2a\u8ba1\u6570\u5668\u7684\u503c\u6765\u8bfb\u53d6\u4e0b\u4e00\u6761\u9700\u8981\u6267\u884c\u7684\u5b57\u8282\u7801\u6307\u4ee4\u3002<\/li>\n\n\n\n<li>\u5b83\u662f\u552f\u4e00\u4e00\u4e2a\u5728java\u865a\u62df\u673a\u89c4\u8303\u4e2d\u6ca1\u6709\u89c4\u5b9a\u4efb\u4f55OOM\u60c5\u51b5\u7684\u533a\u57df\u3002<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u9762\u8bd5\u9898<\/h4>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u5e76\u53d1\u4e0e\u5e76\u884c<\/li>\n\n\n\n<li>\u4e3a\u4ec0\u4e48\u4f7f\u7528PC\u5bc4\u5b58\u5668\u8bb0\u5f55\u5f53\u524d\u7ebf\u7a0b\u7684\u6267\u884c\u5730\u5740<\/li>\n\n\n\n<li>PC\u5bc4\u5b58\u5668\u4e3a\u4ec0\u4e48\u8bbe\u5b9a\u4e3a\u7ebf\u7a0b\u79c1\u6709<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">Java\u865a\u62df\u673a\u6808\uff08Java\u65b9\u6cd5\uff09<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">\u5982\u4f55\u8bbe\u7f6e\u6808\u5927\u5c0f<\/h4>\n\n\n\n<p>\u4f7f\u7528\u53c2\u6570-Xss\u9009\u9879\u6765\u8bbe\u7f6e\u7ebf\u7a0b\u7684\u6700\u5927\u6808\u7a7a\u95f4\uff0c\u6808\u7684\u5927\u5c0f\u76f4\u63a5\u51b3\u5b9a\u4e86\u51fd\u6570\u8c03\u7528\u7684\u6700\u5927\u53ef\u8fbe\u6df1\u5ea6\u3002JDK5.0\u4ee5\u540e\u6bcf\u4e2a\u7ebf\u7a0b\u6808\u5927\u5c0f\u4e3a1M\uff0c\u4ee5\u524d\u6bcf\u4e2a\u7ebf\u7a0b\u6808\u5927\u5c0f\u4e3a256K\u3002\u6839\u636e\u5e94\u7528\u7684\u7ebf\u7a0b\u6240\u9700\u5185\u5b58\u5927\u5c0f\u8fdb\u884c\u8c03\u6574\u3002\u5728\u76f8\u540c\u7269\u7406\u5185\u5b58\u4e0b\uff0c\u51cf\u5c0f\u8fd9\u4e2a\u503c\u80fd\u751f\u6210\u66f4\u591a\u7684\u7ebf\u7a0b\u3002\u4f46\u662f\u64cd\u4f5c\u7cfb\u7edf\u5806\u4e00\u4e2a\u8fdb\u7a0b\u5185\u7684\u7ebf\u7a0b\u6570\u8fd8\u662f\u6709\u9650\u5236\u7684\uff0c\u4e0d\u80fd\u65e0\u9650\u751f\u6210\uff0c\u7ecf\u9a8c\u503c\u57283000\uff5e5000\u5de6\u53f3\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public class StackErrorTest {\n    private static int count = 1;\n\n    public static void main(String&#91;] args) {\n        System.out.println(count);\n        count++;\n        main(args);\n    }\n}<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\">\u865a\u62df\u673a\u6808\u5b58\u50a8\u54ea\u4e9b\u6570\u636e<\/h4>\n\n\n\n<h5 class=\"wp-block-heading\">\u6808\u5e27\u662f\u4ec0\u4e48<\/h5>\n\n\n\n<p>\u6808\u5e27\u662f\u7528\u4e8e\u652f\u6301\u865a\u62df\u673a\u8fdb\u884c\u65b9\u6cd5\u6267\u884c\u7684\u6570\u636e\u7ed3\u6784\u3002\u6808\u5e27\u5b58\u50a8\u4e86\u65b9\u6cd5\u7684\u5c40\u90e8\u53d8\u91cf\u8868\u3001\u64cd\u4f5c\u6570\u6808\u3001\u52a8\u6001\u8fde\u63a5\u548c\u65b9\u6cd5\u8fd4\u56de\u5730\u5740\u7b49\u4fe1\u606f\u3002\u6bcf\u4e00\u4e2a\u65b9\u6cd5\u4ece\u8c03\u7528\u81f3\u6267\u884c\u5b8c\u6210\u7684\u8fc7\u7a0b\uff0c\u90fd\u5bf9\u5e94\u4e00\u4e2a\u6808\u5e27\u5728\u865a\u62df\u673a\u6808\u91cc\u4ece\u5165\u6808\u5230\u51fa\u6808\u7684\u8fc7\u7a0b\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u5f53\u524d\u6808\u5e27<\/h5>\n\n\n\n<p>\u4e00\u4e2a\u7ebf\u7a0b\u4e2d\u65b9\u6cd5\u7684\u8c03\u7528\u94fe\u53ef\u80fd\u4f1a\u5f88\u957f\uff0c\u6240\u4ee5\u4f1a\u6709\u5f88\u591a\u6808\u5e27\u3002\u53ea\u6709\u4f4d\u4e8eJVM\u865a\u62df\u673a\u6808\u6808\u9876\u7684\u5143\u7d20\u624d\u662f\u6709\u6548\u7684\uff0c\u5373\u79f0\u4e3a\u5f53\u524d\u6808\u5e27\uff0c\u4e0e\u8fd9\u4e2a\u6808\u5e27\u76f8\u5173\u8054\u7684\u65b9\u6cd5\u79f0\u4e3a\u5f53\u524d\u65b9\u6cd5\u3001\u5b9a\u4e49\u8fd9\u4e2a\u65b9\u6cd5\u7684\u7c7b\u53eb\u505a\u5f53\u524d\u7c7b\u3002<\/p>\n\n\n\n<p>\u6267\u884c\u5f15\u64ce\u8fd0\u884c\u7684\u6240\u6709\u5b57\u8282\u7801\u6307\u4ee4\u90fd\u53ea\u9488\u5bf9\u5f53\u524d\u6808\u5e27\u8fdb\u884c\u64cd\u4f5c\u3002\u5982\u679c\u5f53\u524d\u65b9\u6cd5\u8c03\u7528\u4e86\u5176\u4ed6\u65b9\u6cd5\uff0c\u6216\u8005\u5f53\u524d\u65b9\u6cd5\u6267\u884c\u7ed3\u675f\uff0c\u90a3\u8fd9\u4e2a\u65b9\u6cd5\u7684\u6808\u5e27\u5c31\u4e0d\u518d\u662f\u5f53\u524d\u6808\u5e27\u4e86\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u4ec0\u4e48\u65f6\u5019\u521b\u5efa\u6808\u5e27<\/h5>\n\n\n\n<p>\u8c03\u7528\u65b0\u7684\u65b9\u6cd5\u65f6\uff0c\u65b0\u7684\u6808\u5e27\u4e5f\u4f1a\u968f\u4e4b\u521b\u5efa\u3002\u5e76\u4e14\u968f\u7740\u7a0b\u5e8f\u63a7\u5236\u6743\u8f6c\u79fb\u5230\u65b0\u65b9\u6cd5\uff0c\u65b0\u7684\u6808\u5e27\u6210\u4e3a\u4e86\u5f53\u524d\u6808\u5e27\uff0c\u65b9\u6cd5\u8fd4\u56de\u4e4b\u9645\uff0c\u539f\u6808\u5e27\u4f1a\u8fd4\u56de\u65b9\u6cd5\u7684\u6267\u884c\u7ed3\u679c\u7ed9\u4e4b\u524d\u7684\u6808\u5e27\uff08\u8fd4\u56de\u7ed9\u65b9\u6cd5\u8c03\u7528\u8005\uff09\uff0c\u968f\u540e\u865a\u62df\u673a\u5c06\u4f1a\u4e22\u5f03\u6b64\u6808\u5e27\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u5c40\u90e8\u53d8\u91cf\u8868<\/h5>\n\n\n\n<ul 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class=\"wp-block-list\">\n<li>this\u5f15\u7528\uff08\u5b9e\u4f8b\u5bf9\u8c61\u90fd\u9700\u8981\u7ef4\u62a4\u7684\u4e00\u4e2a\u53d8\u91cf\uff0c\u800c\u4e14\u5728\u5c40\u90e8\u53d8\u91cf\u8868\u4e2d\u59cb\u7ec8\u5904\u4e8e\u7b2c\u4e00\u4e2a\u4f4d\u7f6e\uff0c\u4e5f\u5c31\u662f\u4e0b\u6807\u4e3a0\u7684\u4f4d\u7f6e\uff09<\/li>\n\n\n\n<li>\u65b9\u6cd5\u53c2\u6570<\/li>\n\n\n\n<li>\u65b9\u6cd5\u5185\u58f0\u660e\u7684\u53d8\u91cf<\/li>\n<\/ul>\n\n\n\n<h6 class=\"wp-block-heading\">\u5b58\u50a8\u5bb9\u91cf<\/h6>\n\n\n\n<p>\u5c40\u90e8\u53d8\u91cf\u8868\u7684\u5bb9\u91cf\u4ee5\u53d8\u91cf\u69fd\u4e3a\u6700\u5c0f\u5355\u4f4d\uff0cJava\u865a\u62df\u673a\u89c4\u8303\u5e76\u6ca1\u6709\u5b9a\u4e49\u4e00\u4e2a\u69fd\u6240\u5e94\u5360\u7528\u7684\u5185\u5b58\u7a7a\u95f4\u7684\u5927\u5c0f\uff0c\u4f46\u662f\u89c4\u5b9a\u4e86\u4e00\u4e2a\u69fd\u5e94\u8be5\u53ef\u4ee5\u5b58\u653e\u4e00\u4e2a32\u4f4d\u4ee5\u5185\u7684\u6570\u636e\u7c7b\u578b\u3002<br>\u5728Java\u7a0b\u5e8f\u7f16\u8bd1\u4e3aClass\u6587\u4ef6\u65f6\uff0c\u5c31\u5728\u65b9\u6cd5\u7684Code\u5c5e\u6027\u4e2d\u7684mac_locals\u6570\u636e\u9879\u4e2d\u786e\u5b9a\u4e86\u8be5\u65b9\u6cd5\u6240\u9700\u5206\u914d\u7684\u5c40\u90e8\u53d8\u91cf\u8868\u7684\u6700\u5927\u5bb9\u91cf\u3002\uff08\u6700\u5927Slot\u6570\u91cf\uff09<br>double\\long\u8fd9\u79cd8\u5b57\u8282\u7c7b\u578b\u7684\u6570\u636e\u3001\u90fd\u9700\u8981\u4e24\u4e2aslot\u6765\u5b58\u50a8\u3002<br>\u865a\u62df\u673a\u901a\u8fc7\u7d22\u5f15\u5b9a\u4f4d\u7684\u65b9\u6cd5\u67e5\u627e\u76f8\u5e94\u7684\u5c40\u90e8\u53d8\u91cf\uff0c\u7d22\u5f15\u7684\u8303\u56f4\u662f\u4ece0\uff5e\u5c40\u90e8\u53d8\u91cf\u8868\u6700\u5927\u5bb9\u91cf\u3002\u5982\u679cSlot\u662f32\u4f4d\u7684\uff0c\u5219\u9047\u5230\u4e00\u4e2a64\u4f4d\u6570\u636e\u7c7b\u578b\u7684\u53d8\u91cf\uff08\u5982long\u6216double\u578b\uff09\u65f6\uff0c\u4f1a\u8fde\u7eed\u4f7f\u7528\u4e24\u4e2a\u8fde\u7eed\u7684Slot\u6765\u5b58\u50a8\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u64cd\u4f5c\u6570\u6808<\/h5>\n\n\n\n<p>\u64cd\u4f5c\u6570\u6808\u4e5f\u79f0\u4e3a\u64cd\u4f5c\u6808\uff0c\u5b83\u662f\u4e00\u4e2a\u540e\u5165\u5148\u51fa\u6808\u3002<br>JVM\u7684\u89e3\u91ca\u5f15\u64ce\u662f\u57fa\u4e8e\uff08\u64cd\u4f5c\u6570\u6808\uff09\u7684\u65b9\u6cd5\u53bb\u6267\u884c\u7684\u3002\uff08\u53e6\u5916\u8fd8\u6709\u4e00\u79cd\u662f\u57fa\u4e8e\u5bc4\u5b58\u5668\u7684\u65b9\u5f0f\uff09\u3002<br>\u5f53\u4e00\u4e2a\u65b9\u6cd5\u521a\u521a\u5f00\u59cb\u6267\u884c\u65f6\uff0c\u5176\u64cd\u4f5c\u6570\u6808\u662f\u7a7a\u7684\u3001\u968f\u7740\u65b9\u6cd5\u6267\u884c\u548c\u5b57\u8282\u7801\u6307\u4ee4\u7684\u6267\u884c\uff0c\u4f1a\u4ece\u5c40\u90e8\u53d8\u91cf\u8868\u6216\u5bf9\u8c61\u5b9e\u4f8b\u7684\u5b57\u6bb5\uff08\u6210\u5458\u53d8\u91cf\uff09\u4e2d\u590d\u5236\u5e38\u91cf\u6216\u53d8\u91cf\u5199\u5165\u5230\u64cd\u4f5c\u6570\u6808\uff0c\u518d\u968f\u7740\u8ba1\u7b97\u7684\u8fdb\u884c\u5c06\u6808\u4e2d\u5143\u7d20\u51fa\u6808\u5230\u5c40\u90e8\u53d8\u91cf\u8868\u6216\u8005\u8fd4\u56de\u7ed9\u65b9\u6cd5\u8c03\u7528\u8005\uff0c\u4e5f\u5c31\u662f\u51fa\u6808\/\u5165\u6808\u64cd\u4f5c\u3002\u4e00\u4e2a\u5b8c\u6574\u7684\u65b9\u6cd5\u6267\u884c\u671f\u95f4\u5f80\u5f80\u5305\u542b\u591a\u4e2a\u8fd9\u6837\u51fa\u6808\/\u5165\u6808\u7684\u8fc7\u7a0b\u3002<\/p>\n\n\n\n<h6 class=\"wp-block-heading\">\u5b58\u50a8\u5185\u5bb9<\/h6>\n\n\n\n<p>\u64cd\u4f5c\u6570\u6808\u7684\u6bcf\u4e00\u4e2a\u5143\u7d20\u53ef\u4ee5\u662f\u4efb\u610fJava\u6570\u636e\u7c7b\u578b\uff0c32\u4f4d\u7684\u6570\u636e\u7c7b\u578b\u5360\u4e00\u4e2a\u6808\u5bb9\u91cf\u300164\u4f4d\u7684\u6570\u636e\u7c7b\u578b\u5360\u4e24\u4e2a\u6808\u5bb9\u91cf\u3002<\/p>\n\n\n\n<h6 class=\"wp-block-heading\">\u5b58\u50a8\u5bb9\u91cf<\/h6>\n\n\n\n<p>\u540c\u5c40\u90e8\u53d8\u91cf\u8868\u4e00\u6837\uff0c\u64cd\u4f5c\u6570\u6808\u7684\u6700\u5927\u6df1\u5ea6\u4e5f\u5728\u7f16\u8bd1\u7684\u65f6\u5019\u5199\u5165\u5230\u65b9\u6cd5\u7684Code\u5c5e\u6027\u7684max_stacks\u6570\u636e\u9879\u4e2d\u3002\u4e14\u5728\u65b9\u6cd5\u6267\u884c\u7684\u4efb\u610f\u65f6\u523b\uff0c\u64cd\u4f5c\u6570\u6808\u7684\u6df1\u5ea6\u90fd\u4e0d\u4f1a\u8d85\u8fc7max_stacks\u4e2d\u8bbe\u7f6e\u7684\u6700\u5927\u503c\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u52a8\u6001\u94fe\u63a5<\/h5>\n\n\n\n<p>\u5728\u4e00\u4e2aclass\u6587\u4ef6\u4e2d\uff0c\u4e00\u4e2a\u65b9\u6cd5\u8981\u8c03\u7528\u5176\u4ed6\u65b9\u6cd5\uff0c\u9700\u8981\u5c06\u8fd9\u4e9b\u65b9\u6cd5\u7684\u7b26\u53f7\u5f15\u7528\u8f6c\u5316\u4e3a\u5176\u4ed6\u5185\u5b58\u5730\u5740\u4e2d\u7684\u76f4\u63a5\u5f15\u7528\u3001\u800c\u7b26\u53f7\u5f15\u7528\u5b58\u5728\u4e8e\u65b9\u6cd5\u533a\u4e2d\u7684\u8fd0\u884c\u65f6\u5e38\u91cf\u6c60\u3002<br>Java\u865a\u62df\u673a\u6808\u4e2d\uff0c\u6bcf\u4e2a\u6808\u5e27\u90fd\u5305\u542b\u4e00\u4e2a\u6267\u884c\u8fd0\u884c\u65f6\u5e38\u91cf\u6c60\u4e2d\u8be5\u6808\u6240\u5c5e\u65b9\u6cd5\u7684\u7b26\u53f7\u5f15\u7528\uff0c\u6301\u6709\u8fd9\u4e2a\u5f15\u7528\u7684\u76ee\u7684\u662f\u4e3a\u4e86\u652f\u6301\u65b9\u6cd5\u8c03\u7528\u8fc7\u7a0b\u4e2d\u7684\u52a8\u6001\u8fde\u63a5\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u7b26\u53f7\u5f15\u7528\uff1a<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"426\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-18-11.42.46-1024x426.png\" alt=\"\" class=\"wp-image-1202\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-18-11.42.46-1024x426.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-18-11.42.46-300x125.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-18-11.42.46-768x320.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/\u622a\u5c4f2024-07-18-11.42.46.png 1052w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u76f4\u63a5\u5f15\u7528\u3002\u5c31\u662f\u5bf9\u5e94\u65b9\u6cd5\u7684\u5185\u5b58\u5730\u5740\u3002<\/li>\n<\/ul>\n\n\n\n<h5 class=\"wp-block-heading\">\u65b9\u6cd5\u8fd4\u56de<\/h5>\n\n\n\n<p>\u5f53\u4e00\u4e2a\u65b9\u6cd5\u5f00\u59cb\u6267\u884c\u65f6\uff0c\u53ef\u80fd\u6709\u4e24\u79cd\u65b9\u5f0f\u9000\u51fa\u8be5\u65b9\u6cd5\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6b63\u5e38\u5b8c\u6210\u51fa\u53e3<\/li>\n\n\n\n<li>\u5f02\u5e38\u5b8c\u6210\u51fa\u53e3<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u6808\u8fd0\u884c\u539f\u7406<\/h4>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"670\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-37-1024x670.png\" alt=\"\" class=\"wp-image-1203\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-37-1024x670.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-37-300x196.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-37-768x502.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-37.png 1290w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code><\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\">\u76f8\u5173\u9762\u8bd5\u9898<\/h4>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u4e3e\u4f8b\u6808\u6ea2\u51fa\u7684\u60c5\u51b5<br>\u9012\u5f52\u8c03\u7528\u7b49\u3002\u89e3\u51b3\u65b9\u6cd5\u901a\u8fc7-Xss\u8bbe\u7f6e\u6808\u7684\u5927\u5c0f\u3002<\/li>\n\n\n\n<li>\u8c03\u6574\u6808\u7684\u5927\u5c0f\uff0c\u5c31\u80fd\u4fdd\u8bc1\u4e0d\u6ea2\u51fa\u5417\uff1f<br>\u4e0d\u80fd\uff0c\u5982\u679c\u9012\u5f52\u65e0\u9650\u6b21\u80af\u5b9a\u4f1a\u6ea2\u51fa\uff0c\u8c03\u6574\u6808\u5927\u5c0f\u53ea\u80fd\u4fdd\u8bc1\u6ea2\u51fa\u7684\u65f6\u95f4\u80fd\u665a\u4e00\u4e9b\uff0c\u6781\u9650\u60c5\u51b5\u4f1a\u5bfc\u81f4OOM\u5185\u5b58\u6ea2\u51fa<\/li>\n\n\n\n<li>\u5206\u914d\u7684\u6808\u5185\u5b58\u8d8a\u5927\u8d8a\u597d\u5417\uff1f<br>\u4e0d\u4f1a\uff0c\u4f1a\u6324\u5360\u5176\u4ed6\u7ebf\u7a0b\u7684\u7a7a\u95f4<\/li>\n\n\n\n<li>\u5783\u573e\u56de\u6536\u662f\u5426\u4f1a\u7275\u6d89\u5230\u865a\u62df\u673a\u6808<br>\u4e0d\u4f1a<\/li>\n\n\n\n<li>\u65b9\u6cd5\u4e2d\u5b9a\u4e49\u7684\u5c40\u90e8\u53d8\u91cf\u662f\u5426\u7ebf\u7a0b\u5b89\u5168<br>\u5177\u4f53\u60c5\u51b5\u5177\u4f53\u5206\u6790<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">\u672c\u5730\u65b9\u6cd5\u6808<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">\u4ec0\u4e48\u662f\u672c\u5730\u65b9\u6cd5\u6808<\/h4>\n\n\n\n<p>\u672c\u5730\u65b9\u6cd5\u6808\u548c\u865a\u62df\u673a\u6808\u76f8\u4f3c\uff0c\u533a\u522b\u5c31\u662f\u865a\u62df\u673a\u6808\u4e3a\u865a\u62df\u673a\u6267\u884cJava\u670d\u52a1\uff08\u5b57\u8282\u7801\u670d\u52a1\uff09\uff0c\u800c\u672c\u5730\u65b9\u6cd5\u4e3a\u865a\u62df\u673a\u4f7f\u7528\u5230\u7684Native\u65b9\u6cd5\uff08\u6bd4\u5982C++\u65b9\u6cd5\uff09\u670d\u52a1\u3002\u7b80\u5355\u5730\u8bb2\uff0c\u4e00\u4e2aNative Method\u5c31\u662f\u4e00\u4e2ajava\u8c03\u7528\u975ejava\u4ee3\u7801\u7684\u63a5\u53e3\u3002\u4e00\u4e2aNative Method\u662f\u8fd9\u6837\u4e00\u4e2ajava\u7684\u65b9\u6cd5\uff1a\u8be5\u65b9\u6cd5\u7684\u5b9e\u73b0\u7531\u975ejava\u8bed\u8a00\u5b9e\u73b0\uff0c\u6bd4\u5982C\u3002<\/p>\n\n\n\n<p>\u5728\u5b9a\u4e49\u4e00\u4e2anative method\u65f6\uff0c\u5e76\u4e0d\u63d0\u4f9b\u5b9e\u73b0\u4f53\uff08\u6709\u4e9b\u50cf\u5b9a\u4e49\u4e00\u4e2ajava interface\uff09\uff0c\u56e0\u4e3a\u5176\u5b9e\u73b0\u4f53\u662f\u7531\u975ejava\u8bed\u8a00\u5728\u5916\u9762\u5b9e\u73b0\u7684\u3002\u4e0b\u9762\u7ed9\u4e86\u4e00\u4e2a\u5b9e\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public class IHaveNative {\n    native public void native1(int x);\n    native static public long native2();\n    native synchronized private float native3(Object o);\n    native void native4(int&#91;] array) throws Exception;\n}<\/code><\/pre>\n\n\n\n<p>\u672c\u5730\u63a5\u53e3\u7684\u4f5c\u7528\u662f\u878d\u5408\u4e0d\u540c\u7684\u7f16\u7a0b\u8bed\u8a00\u4e3ajava\u6240\u7528\uff0c\u5b83\u7684\u521d\u8877\u662f\u878d\u5408C\/C++\u7a0b\u5e8f\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u4e3a\u4ec0\u4e48\u8981\u4f7f\u7528\u672c\u5730\u65b9\u6cd5<\/h4>\n\n\n\n<p>\u6709\u65f6java\u9700\u8981\u4e0ejava\u5916\u7684\u73af\u5883\u8fdb\u884c\u4ea4\u4e92\uff0c\u8fd9\u662f\u672c\u5730\u65b9\u6cd5\u5b58\u5728\u7684\u4e3b\u8981\u539f\u56e0\uff0c\u5982\u4e0e\u64cd\u4f5c\u7cfb\u7edf\u4ea4\u4e92\u65f6\u3001\u4e0e\u8bbe\u5907\u4ea4\u4e92\u65f6\u3001\u591a\u7ebf\u7a0b\u64cd\u4f5c\u7ebf\u7a0b\u5524\u9192\u548c\u6682\u505c\u65f6\u7b49\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u672c\u5730\u65b9\u6cd5\u6808\u7684\u4f7f\u7528\u6d41\u7a0b<\/h4>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"674\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-40-1024x674.png\" alt=\"\" class=\"wp-image-1207\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-40-1024x674.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-40-300x197.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-40-768x506.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-40.png 1276w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">\u4e00\u4e2a\u7ebf\u7a0b\u8c03\u7528java\u65b9\u6cd5\u548c\u672c\u5730\u65b9\u6cd5\u65f6\u7684\u6808<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">\u65b9\u6cd5\u6267\u884c<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">\u5b57\u8282\u7801\u6307\u4ee4\u96c6<\/h4>\n\n\n\n<h5 class=\"wp-block-heading\">\u4ec0\u4e48\u662f\u5b57\u8282\u7801\u6307\u4ee4\u96c6<\/h5>\n\n\n\n<p>Java\u5b57\u8282\u7801\u6307\u4ee4\u7531\u64cd\u4f5c\u7801\u548c\u64cd\u4f5c\u6570\u6784\u6210\u3002\u5176\u4e2dJVM\u89c4\u5b9a\u64cd\u4f5c\u7801\u7684\u957f\u5ea6\u4e3a\u4e00\u4e2a\u5b57\u8282\uff080-255\uff09\uff0c\u4e5f\u5c31\u662f\u5b57\u8282\u7801\u7684\u603b\u91cf\u4e0d\u4f1a\u8d85\u8fc7256\u4e2a\u3002<br>\u7531\u4e8eJava\u865a\u62df\u673a\u91c7\u7528\u9762\u5411\u64cd\u4f5c\u6570\u6808\u800c\u4e0d\u662f\u5bc4\u5b58\u5668\u7684\u67b6\u6784\uff0c\u6240\u4ee5\u5927\u591a\u6570\u7684\u6307\u4ee4\u90fd\u4e0d\u5305\u542b\u64cd\u4f5c\u6570\uff0c\u53ea\u6709\u4e00\u4e2a\u64cd\u4f5c\u7801\u3002<\/p>\n\n\n\n<p>\u5b9e\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>iconst_0      \u64cd\u4f5c\u7801\nbipush 10     \u64cd\u4f5c\u7801 + \u64cd\u4f5c\u6570<\/code><\/pre>\n\n\n\n<h5 class=\"wp-block-heading\">\u90fd\u6709\u54ea\u4e9b\u5b57\u8282\u7801\u6307\u4ee4<\/h5>\n\n\n\n<h6 class=\"wp-block-heading\">\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/h6>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u9664\u4e86long\u548cdouble\u7c7b\u578b\u5916\uff0c\u6bcf\u4e2a\u53d8\u91cf\u90fd\u5360\u5c40\u90e8\u53d8\u91cf\u533a\u4e2d\u7684\u4e00\u4e2a\u53d8\u91cf\u69fd\uff0c\u800clong\u53cadouble\u4f1a\u5360\u7528\u4e24\u4e2a\u8fde\u7eed\u7684\u53d8\u91cf\u69fd\u3002<\/li>\n\n\n\n<li>\u5927\u591a\u6570\u5bf9\u4e8eboolean\u3001byte\u3001short\u548cchar\u7c7b\u578b\u6570\u636e\u7684\u64cd\u4f5c\uff0c\u90fd\u662f\u7528\u76f8\u5e94\u7684int\u7c7b\u578b\u4f5c\u4e3a\u8fd0\u7b97\u7c7b\u578b\u3002<\/li>\n<\/ol>\n\n\n\n<h6 class=\"wp-block-heading\">\u52a0\u8f7d\u548c\u5b58\u50a8\u6307\u4ee4\uff08\u603b\uff09<\/h6>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u5c06\u4e00\u4e2a<strong>\u5c40\u90e8\u53d8\u91cf\u8868<\/strong>\u52a0\u8f7d\u5230<strong>\u64cd\u4f5c\u6570\u6808<\/strong>\u3002<\/li>\n\n\n\n<li>\u5c06\u4e00\u4e2a\u6570\u503c\u4ece<strong>\u64cd\u4f5c\u6570\u6808<\/strong>\u5b58\u50a8\u5230<strong>\u5c40\u90e8\u53d8\u91cf\u8868<\/strong>\u3002<\/li>\n\n\n\n<li>\u5c06\u4e00\u4e2a<strong>\u5e38\u91cf<\/strong>\u52a0\u8f7d\u5230\u64cd\u4f5c\u6570\u6808\u3002<\/li>\n\n\n\n<li>\u6269\u5145\u5c40\u90e8\u53d8\u91cf\u8868\u7684\u8bbf\u95ee\u7d22\u5f15\u6307\u4ee4\u3002<\/li>\n<\/ol>\n\n\n\n<h6 class=\"wp-block-heading\">const\u7cfb\u5217\uff08\u5c0f\u6570\u503c\uff09<\/h6>\n\n\n\n<p>\u8be5\u7cfb\u5217\u547d\u4ee4\u4e3b\u8981\u8d1f\u8d23\u628a<strong>\u7b80\u5355\u7684\u6570\u503c\u7c7b\u578b<\/strong>\u9001\u5230<strong>\u64cd\u4f5c\u6570\u6808\u6808\u9876<\/strong>\u3002\u8be5\u7cfb\u5217\u547d\u4ee4\u4e0d\u5e26\u53c2\u6570\u3002<\/p>\n\n\n\n<h6 class=\"wp-block-heading\">push\u7cfb\u5217\uff08\u4e2d\u6570\u503c\uff09<\/h6>\n\n\n\n<p>\u8be5\u7cfb\u5217\u547d\u4ee4\u4e3b\u8981\u8d1f\u8d23\u628a<strong>\u6574\u5f62\u6570\u5b57<\/strong>\uff08\u957f\u5ea6\u6bd4\u8f83\u5c0f\uff09\u9001\u5230<strong>\u64cd\u4f5c\u6570\u6808\u6808\u9876<\/strong>\u3002\u8be5\u7cfb\u5217\u547d\u4ee4\u6709\u4e00\u4e2a\u53c2\u6570\u3002<\/p>\n\n\n\n<h6 class=\"wp-block-heading\">ldc\u7cfb\u5217\uff08\u5927\u6570\u503c\u6216\u5b57\u7b26\u4e32\u5e38\u91cf\uff09<\/h6>\n\n\n\n<p>\u8be5\u7cfb\u5217\u547d\u4ee4\u8d1f\u8d23\u628a\u957f<strong>\u5ea6\u6bd4\u8f83\u957f\u7684\u6570\u503c\u5e38\u91cf<\/strong>\u6216<strong>string\u5e38\u91cf\u503c<\/strong>\u4ece<strong>\u5e38\u91cf\u6c60<\/strong>\u4e2d\u63a8\u9001\u81f3<strong>\u64cd\u4f5c\u6570\u6808\u6808\u9876<\/strong>\u3002\u8be5\u547d\u4ee4\u540e\u9762\u9700\u8981\u7ed9\u4e00\u4e2a\u8868\u793a\u5e38\u91cf\u5728\u5e38\u91cf\u6c60\u4e2d\u4f4d\u7f6e\u7684\u53c2\u6570\u3002<\/p>\n\n\n\n<h6 class=\"wp-block-heading\">load\u7cfb\u5217<\/h6>\n\n\n\n<ul class=\"wp-block-list\">\n<li>load\u7cfb\u5217A\u3002\u8d1f\u8d23\u628a<strong>\u672c\u5730\u53d8\u91cf\u8868<\/strong>\u4e2d\u7684\u503c\u9001\u5230<strong>\u64cd\u4f5c\u6570\u6808\u6808\u9876<\/strong>\u3002\u8fd9\u91cc\u7684\u672c\u5730\u53d8\u91cf\u4e0d\u4ec5\u53ef\u4ee5\u662f\u6570\u503c\u7c7b\u578b\uff0c\u8fd8\u53ef\u4ee5\u662f\u5f15\u7528\u7c7b\u578b\u3002<\/li>\n\n\n\n<li>load\u7cfb\u5217B\u3002\u8d1f\u8d23\u628a<strong>\u6570\u7ec4\u7684\u67d0\u9879<\/strong>\u9001\u5230<strong>\u6808\u9876<\/strong>\u3002\u8be5\u547d\u4ee4\u6839\u636e\u6808\u91cc\u5185\u5bb9\u6765\u786e\u5b9a\u5bf9\u90a3\u4e2a\u6570\u7ec4\u7684\u54ea\u9879\u8fdb\u884c\u64cd\u4f5c\u3002<\/li>\n<\/ul>\n\n\n\n<h6 class=\"wp-block-heading\">store\u7cfb\u5217<\/h6>\n\n\n\n<ul class=\"wp-block-list\">\n<li>store\u7cfb\u5217A\u3002\u8d1f\u8d23\u628a<strong>\u64cd\u4f5c\u6570\u6808\u6808\u9876<\/strong>\u7684\u503c\u5b58\u5165<strong>\u672c\u5730\u53d8\u91cf\u8868<\/strong>\u3002\u8fd9\u91cc\u7684\u672c\u5730\u53d8\u91cf\u4e0d\u4ec5\u53ef\u4ee5\u662f\u6570\u503c\u7c7b\u578b\uff0c\u8fd8\u53ef\u4ee5\u662f\u5f15\u7528\u7c7b\u578b\u3002<\/li>\n\n\n\n<li>store\u7cfb\u5217B\u3002\u8d1f\u8d23\u628a<strong>\u6808\u9876\u9879<\/strong>\u7684\u503c\u5b58\u5230<strong>\u6570\u7ec4<\/strong>\u91cc\u3002\u6839\u636e\u6808\u91cc\u5185\u5bb9\u51b3\u5b9a\u5bf9\u54ea\u4e2a\u6570\u7ec4\u7684\u90a3\u9879\u8fdb\u884c\u64cd\u4f5c\u3002<\/li>\n<\/ul>\n\n\n\n<h6 class=\"wp-block-heading\">pop\u7cfb\u5217<\/h6>\n\n\n\n<p>\u53ea\u662f\u7b80\u5355\u5730\u5bf9\u6808\u9876\u8fdb\u884c\u64cd\u4f5c\u3002<\/p>\n\n\n\n<h6 class=\"wp-block-heading\">\u6808\u9876\u5143\u7d20\u6570\u5b66\u64cd\u4f5c\u53ca\u79fb\u4f4d\u64cd\u4f5c\u7cfb\u5217<\/h6>\n\n\n\n<p>\u8be5\u7cfb\u5217\u547d\u4ee4\u8d1f\u8d23<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u5e38\u89c1\u8bed\u6cd5\u7684\u5b57\u8282\u7801\u6307\u4ee4<\/h5>\n\n\n\n<h6 class=\"wp-block-heading\">\u540c\u6b65\u9501<\/h6>\n\n\n\n<pre class=\"wp-block-code\"><code>public class SyncTest {\n    final Object lock = new Object();\n\n    public void doLock() {\n        synchronized (lock) {\n            System.out.println(\"\u6d4b\u8bd5synchronized\u5b57\u8282\u7801\");\n        }\n    }\n}<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code> 0 aload_0\n 1 getfield #3 &lt;SyncTest.lock : Ljava\/lang\/Object;&gt;\n 4 dup\n 5 astore_1\n 6 monitorenter\n 7 getstatic #4 &lt;java\/lang\/System.out : Ljava\/io\/PrintStream;&gt;\n10 ldc #5 &lt;\u6d4b\u8bd5synchronized\u5b57\u8282\u7801&gt;\n12 invokevirtual #6 &lt;java\/io\/PrintStream.println : (Ljava\/lang\/String;)V&gt;\n15 aload_1\n16 monitorexit\n17 goto 25 (+8)\n20 astore_2\n21 aload_1\n22 monitorexit\n23 aload_2\n24 athrow\n25 return<\/code><\/pre>\n\n\n\n<h6 class=\"wp-block-heading\">\u88c5\u7bb1\u548c\u62c6\u7bb1<\/h6>\n\n\n\n<pre class=\"wp-block-code\"><code>public class BoxTest {\n    public Integer cal() {\n        Integer a = 1000;\n        int b = a * 10;\n        return b;\n    }\n}<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code> 0 sipush 1000\n 3 invokestatic #2 &lt;java\/lang\/Integer.valueOf : (I)Ljava\/lang\/Integer;&gt;\n 6 astore_1\n 7 aload_1\n 8 invokevirtual #3 &lt;java\/lang\/Integer.intValue : ()I&gt;\n11 bipush 10\n13 imul\n14 istore_2\n15 iload_2\n16 invokestatic #2 &lt;java\/lang\/Integer.valueOf : (I)Ljava\/lang\/Integer;&gt;\n19 areturn<\/code><\/pre>\n\n\n\n<h6 class=\"wp-block-heading\">\u6570\u7ec4<\/h6>\n\n\n\n<pre class=\"wp-block-code\"><code>public class ArrayTest {\n    public int getValue() {\n        int&#91;] arr = new int&#91;]{100, 200, 300, 400};\n        return arr&#91;2];\n    }\n\n    public int getLength(int&#91;] arr) {\n        return arr.length;\n    }\n}<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code> 0 iconst_4\n 1 newarray 10 (int)\n 3 dup\n 4 iconst_0\n 5 bipush 100\n 7 iastore\n 8 dup\n 9 iconst_1\n10 sipush 200\n13 iastore\n14 dup\n15 iconst_2\n16 sipush 300\n19 iastore\n20 dup\n21 iconst_3\n22 sipush 400\n25 iastore\n26 astore_1\n27 aload_1\n28 iconst_2\n29 iaload\n30 ireturn<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\">JVM\u7a0b\u5e8f\u6267\u884c\u6d41\u7a0b<\/h4>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1018\" src=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-44-1024x1018.png\" alt=\"\" class=\"wp-image-1214\" style=\"width:736px;height:auto\" srcset=\"http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-44-1024x1018.png 1024w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-44-300x298.png 300w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-44-150x150.png 150w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-44-768x764.png 768w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-44-60x60.png 60w, http:\/\/www.spiceandwolf.com.cn\/wp-content\/uploads\/2024\/07\/image-44.png 1060w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h5 class=\"wp-block-heading\">\u4ec0\u4e48\u662f\u5373\u4f7f\u7f16\u8bd1\u5668\uff1f<\/h5>\n\n\n\n<p>\u5373\u65f6\u7f16\u8bd1\u5668\uff08Just In Time Compiler\uff09\uff0c\u53c8\u79f0JIT\u7f16\u8bd1\u5668\u3002<br>\u5728\u90e8\u5206\u5546\u7528\u865a\u62df\u673a\u4e2d\uff08\u5982HotSpot\uff09\uff0cJava\u7a0b\u5e8f\u6700\u521d\u662f\u901a\u8fc7\u89e3\u91ca\u5668\uff08Interpreter\uff09\u8fdb\u884c\u89e3\u91ca\u6267\u884c\u7684\uff0c\u5f53\u865a\u62df\u673a\u53d1\u73b0\u67d0\u4e2a\u65b9\u6cd5\u6216\u4ee3\u7801\u7684\u8fd0\u884c\u7279\u522b\u9891\u7e41\u65f6\uff0c\u5c31\u4f1a\u628a\u8fd9\u4e9b\u4ee3\u7801\u8ba4\u5b9a\u4e3a&#8221;\u70ed\u70b9\u4ee3\u7801&#8221;\u3002\u4e3a\u4e86\u63d0\u9ad8\u70ed\u70b9\u4ee3\u7801\u7684\u6267\u884c\u6548\u7387\uff0c\u5728\u8fd0\u884c\u65f6\uff0c\u865a\u62df\u673a\u5c06\u4f1a\u628a\u8fd9\u4e9b\u4ee3\u7801\u7f16\u8bd1\u6210\u4e0e\u672c\u5730\u5e73\u53f0\u76f8\u5173\u7684\u673a\u5668\u7801\uff0c\u5e76\u8fdb\u884c\u5404\u79cd\u5c42\u6b21\u7684\u4f18\u5316\uff0c\u5b8c\u6210\u8fd9\u4e2a\u4efb\u52a1\u7684\u7f16\u8bd1\u5668\u79f0\u4e3a\u5373\u65f6\u7f16\u8bd1\u5668\u3002<br>\u7531\u4e8eJava\u865a\u62df\u673a\u89c4\u8303\u5e76\u6ca1\u6709\u5177\u4f53\u7684\u7ea6\u675f\u89c4\u5219\u53bb\u9650\u5236\u5373\u65f6\u7f16\u8bd1\u5668\u5e94\u8be5\u5982\u4f55\u5b9e\u73b0\uff0c\u6240\u4ee5\u8fd9\u90e8\u5206\u529f\u80fd\u5b8c\u5168\u662f\u4e0e\u865a\u62df\u673a\u5177\u4f53\u5b9e\u73b0\u76f8\u5173\u7684\u5185\u5bb9\uff0c\u5982\u65e0\u7279\u6b8a\u8bf4\u660e\uff0c\u6211\u4eec\u63d0\u5230\u7684\u7f16\u8bd1\u5668\u3001\u5373\u65f6\u7f16\u8bd1\u5668\u90fd\u662f\u6307Hotspot\u865a\u62df\u673a\u5185\u7684\u5373\u65f6\u7f16\u8bd1\u5668\uff0c\u865a\u62df\u673a\u4e5f\u662f\u7279\u6307Hotspot\u865a\u62df\u673a\u3002<br>\u6211\u4eec\u7684JIT\u662f\u5c5e\u4e8e\u52a8\u6001\u7f16\u8bd1\u65b9\u5f0f\u7684\uff0c\u52a8\u6001\u7f16\u8bd1\u6307\u7684\u662f&#8221;\u5728\u8fd0\u884c\u65f6\u8fdb\u884c\u7f16\u8bd1&#8221;\uff1b\u4e0e\u4e4b\u76f8\u5bf9\u7684\u662f\u4e8b\u524d\u7f16\u8bd1\uff0c\u4e5f\u53eb\u9759\u6001\u7f16\u8bd1\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u4ec0\u4e48\u662f\u70ed\u70b9\u4ee3\u7801\uff1f<\/h5>\n\n\n\n<p>\u8fd0\u884c\u8fc7\u7a0b\u4e2d\u4f1a\u88ab\u53ca\u65f6\u7f16\u8bd1\u5668\u7f16\u8bd1\u7684&#8221;\u70ed\u70b9\u4ee3\u7801&#8221;\u6709\u4e24\u7c7b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u88ab\u591a\u6b21\u8c03\u7528\u7684\u65b9\u6cd5<\/li>\n\n\n\n<li>\u88ab\u591a\u6b21\u6267\u884c\u7684\u5faa\u73af\u4f53<\/li>\n<\/ul>\n\n\n\n<p>\u4e24\u79cd\u60c5\u51b5\uff0c\u7f16\u8bd1\u5668\u90fd\u662f\u4ee5\u6574\u4e2a\u65b9\u6cd5\u4f5c\u4e3a\u7f16\u8bd1\u5bf9\u8c61\u3002\u8fd9\u79cd\u7f16\u8bd1\u65b9\u6cd5\u56e0\u4e3a\u7f16\u8bd1\u53d1\u751f\u5728\u65b9\u6cd5\u6267\u884c\u8fc7\u7a0b\u4e4b\u4e2d\uff0c\u56e0\u6b64\u5f62\u8c61\u7684\u79f0\u4e4b\u4e3a\u6808\u4e0a\u66ff\u6362\uff0c\u5373\u65b9\u6cd5\u6808\u5e27\u8fd8\u5728\u6808\u4e0a\uff0c\u65b9\u6cd5\u5c31\u88ab\u66ff\u6362\u4e86\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u70ed\u70b9\u68c0\u6d4b\u65b9\u5f0f<\/h5>\n\n\n\n<p>\u76ee\u524d\u4e3b\u8981\u7684\u63a2\u6d4b\u65b9\u5f0f\u6709\u4e24\u79cd\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u57fa\u4e8e\u91c7\u6837\u7684\u70ed\u70b9\u63a2\u6d4b\u3002<\/li>\n\n\n\n<li>\u57fa\u4e8e\u8ba1\u6570\u5668\u7684\u70ed\u70b9\u63a2\u6d4b\u3002<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u91ca\u5668\u6267\u884c<\/h4>\n\n\n\n<h4 class=\"wp-block-heading\">\u7f16\u8bd1\u5668\u6267\u884c\u4e4bJIT\u4f7f\u7528<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e3a\u4f55HotSpot\u9700\u8981\u4f7f\u7528\u89e3\u91ca\u5668\u548c\u7f16\u8bd1\u5668\u5e76\u5b58\u7684\u67b6\u6784\uff1f<\/li>\n\n\n\n<li>JVM\u4e3a\u4ec0\u4e48\u8981\u5b9e\u73b0\u4e24\u4e2a\u4e0d\u540c\u7684\u5373\u65f6\u7f16\u8bd1\u5668\uff1f<\/li>\n\n\n\n<li>\u7a0b\u5e8f\u4f55\u65f6\u4f1a\u4f7f\u7528\u89e3\u91ca\u5668\u6267\u884c\uff1f\u4f55\u65f6\u4f1a\u4f7f\u7528\u7f16\u8bd1\u5668\u6267\u884c\uff1f<\/li>\n\n\n\n<li>\u54ea\u4e2a\u7a0b\u5e8f\u4ee3\u7801\u4f1a\u88ab\u7f16\u8bd1\u6210\u4e3a\u672c\u5730\u4ee3\u7801\uff1f\u5982\u4f55\u7f16\u8bd1\uff1f<\/li>\n\n\n\n<li>JAVA\u4ee3\u7801\u7684\u6267\u884c\u6548\u7387\u5c31\u4e00\u5b9a\u6bd4C\u3001C++\u9759\u6001\u6267\u884c\u7684\u6548\u7387\u4f4e\uff1fJAVA\u4ee3\u7801\u89e3\u6790\u6267\u884c\u6709\u4f55\u4f18\u52bf\uff1f<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u7f16\u8bd1\u5668\u6267\u884c\u4e4bJIT\u4f18\u5316<\/h4>\n\n\n\n<p>HotSpot\u865a\u62df\u673a\u4f7f\u7528\u4e86\u5f88\u591a\u79cd\u4f18\u5316\u6280\u672f\uff0c\u8fd9\u91cc\u53ea\u7b80\u5355\u4ecb\u7ecd\u5176\u4e2d\u7684\u51e0\u79cd\uff0c\u5b8c\u6574\u7684\u4f18\u5316\u6280\u672f\u4ecb\u7ecd\u53ef\u4ee5\u53c2\u8003\u5b98\u7f51\u5185\u5bb9\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u516c\u5171\u5b50\u8868\u8fbe\u5f0f\u7684\u6d88\u9664<\/h5>\n\n\n\n<p>\u516c\u5171\u5b50\u8868\u8fbe\u5f0f\u6d88\u9664\u662f\u4e00\u4e2a\u666e\u904d\u5e94\u7528\u4e8e\u5404\u79cd\u7f16\u8bd1\u5668\u7684\u7ecf\u5178\u4f18\u5316\u6280\u672f\uff0c\u5b83\u7684\u542b\u4e49\u662f\uff1a\u5982\u679c\u4e00\u4e2a\u8868\u8fbe\u5f0fE\u5df2\u7ecf\u8ba1\u7b97\u8fc7\u4e86\uff0c\u5e76\u4e14\u4ece\u5148\u524d\u5230\u73b0\u5728E\u4e2d\u6240\u6709\u53d8\u91cf\u7684\u503c\u90fd\u6ca1\u6709\u53d1\u751f\u53d8\u5316\u3001\u90a3\u4e48E\u7684\u8fd9\u6b21\u51fa\u73b0\u5c31\u6210\u4e3a\u4e86\u516c\u5171\u5b50\u8868\u8fbe\u5f0f\u3002<br>\u5bf9\u4e8e\u8fd9\u79cd\u8868\u8fbe\u5f0f\uff0c\u6ca1\u6709\u5fc5\u8981\u82b1\u65f6\u95f4\u518d\u5bf9\u5b83\u8fdb\u884c\u8ba1\u7b97\uff0c\u53ea\u9700\u8981\u76f4\u63a5\u7528\u524d\u9762\u8ba1\u7b97\u8fc7\u7684\u8868\u8fbe\u5f0f\u7ed3\u679c\u4ee3\u66ffE\u5c31\u53ef\u4ee5\u4e86\u3002<br>\u5982\u679c\u8fd9\u79cd\u4f18\u5316\u4ec5\u9650\u4e8e\u7a0b\u5e8f\u7684\u57fa\u672c\u5757\u5185\uff0c\u53d8\u6210\u4e3a\u5c40\u90e8\u516c\u5171\u5b50\u8868\u8fbe\u5f0f\u6d88\u9664\u3002<br>\u5982\u679c\u8fd9\u79cd\u4f18\u5316\u8303\u56f4\u6db5\u76d6\u4e86\u591a\u4e2a\u57fa\u672c\u5757\uff0c\u90a3\u5c31\u6210\u4e3a\u5168\u5c40\u516c\u5171\u5b50\u8868\u8fbe\u5f0f\u6d88\u9664\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u65b9\u6cd5\u5185\u8054<\/h5>\n\n\n\n<p>\u5728\u4f7f\u7528JIT\u8fdb\u884c\u5373\u65f6\u7f16\u8bd1\u65f6\uff0c\u5c06\u65b9\u6cd5\u8c03\u7528\u76f4\u63a5\u4f7f\u7528\u65b9\u6cd5\u4f53\u4e2d\u7684\u4ee3\u7801\u8fdb\u884c\u66ff\u6362\uff0c\u8fd9\u5c31\u662f\u65b9\u6cd5\u5185\u8054\uff0c\u51cf\u5c11\u4e86\u65b9\u6cd5\u8c03\u7528\u8fc7\u7a0b\u4e2d\u538b\u6808\u4e0e\u5165\u6808\u7684\u5f00\u9500\u3002\u540c\u65f6\u4e3a\u4e4b\u540e\u7684\u4e00\u4e9b\u4f18\u5316\u624b\u6bb5\u63d0\u4f9b\u6761\u4ef6\u3002\u5982\u679cJVM\u68c0\u6d4b\u5230\u4e00\u4e9b\u5c0f\u65b9\u6cd5\u88ab\u9891\u7e41\u7684\u6267\u884c\uff0c\u5b83\u4f1a\u628a\u65b9\u6cd5\u7684\u8c03\u7528\u66ff\u6362\u6210\u65b9\u6cd5\u4f53\u672c\u8eab\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u65b9\u6cd5\u9003\u9038\u5206\u6790<\/h5>\n\n\n\n<p>\u9003\u9038\u5206\u6790\u662f\u76ee\u524dJava\u865a\u62df\u673a\u4e2d\u6bd4\u8f83\u524d\u6cbf\u7684\u4f18\u5316\u6280\u672f\u3002\u8fd9\u662f\u4e00\u79cd\u53ef\u4ee5\u6709\u6548\u51cf\u5c11Java\u7a0b\u5e8f\u4e2d\u540c\u6b65\u8d1f\u8f7d\u548c\u5185\u5b58\u5806\u5206\u914d\u538b\u529b\u7684\u8de8\u51fd\u6570\u5168\u5c40\u6570\u636e\u6d41\u5206\u6790\u7b97\u6cd5\u3002\u901a\u8fc7\u9003\u9038\u5206\u6790\u3001Java 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class=\"wp-block-list\">\n<li>\u5168\u5c40\u53d8\u91cf\u8d4b\u503c\u9003\u9038<\/li>\n\n\n\n<li>\u65b9\u6cd5\u8fd4\u56de\u503c\u9003\u9038<\/li>\n\n\n\n<li>\u5b9e\u4f8b\u5f15\u7528\u53d1\u751f\u9003\u9038<\/li>\n\n\n\n<li>\u7ebf\u7a0b\u9003\u9038\uff1a\u8d4b\u503c\u7ed9\u7c7b\u53d8\u91cf\u6216\u53ef\u4ee5\u5728\u5176\u4ed6\u7ebf\u7a0b\u4e2d\u8bbf\u95ee\u7684\u5b9e\u4f8b\u53d8\u91cf<\/li>\n<\/ul>\n\n\n\n<h5 class=\"wp-block-heading\">\u5bf9\u8c61\u7684\u6808\u4e0a\u5185\u5b58\u5206\u914d<\/h5>\n\n\n\n<p>\u6211\u4eec\u77e5\u9053\uff0c\u5728\u4e00\u822c\u60c5\u51b5\u4e0b\uff0c\u5bf9\u8c61\u548c\u6570\u7ec4\u5143\u7d20\u7684\u5185\u5b58\u5206\u914d\u662f\u5728\u5806\u5185\u5b58\u4e0a\u8fdb\u884c\u7684\u3002\u4f46\u662f\u968f\u7740JIT\u7f16\u8bd1\u5668\u7684\u65e5\u6e10\u6210\u719f\uff0c\u5f88\u591a\u4f18\u5316\u4f7f\u8fd9\u79cd\u5206\u914d\u7b56\u7565\u5e76\u4e0d\u7edd\u5bf9\u3002JIT\u7f16\u8bd1\u5668\u5c31\u53ef\u4ee5\u5728\u7f16\u8bd1\u5668\u89c1\u6839\u636e\u9003\u9038\u5206\u6790\u7684\u7ed3\u679c\uff0c\u6765\u51b3\u5b9a\u662f\u5426\u53ef\u4ee5\u5c06\u5bf9\u8c61\u7684\u5185\u5b58\u5206\u914d\u4ece\u5806\u8f6c\u5316\u4e3a\u6808\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u6807\u91cf\u66ff\u6362<\/h5>\n\n\n\n<p>\u6807\u91cf\u662f\u6307\u4e00\u4e2a\u65e0\u6cd5\u518d\u5206\u89e3\u6210\u66f4\u5c0f\u7684\u6570\u636e\u7684\u6570\u636e\u3002\u4e0e\u4e4b\u5bf9\u5e94\u7684\u6709\u4e00\u4e2a\u805a\u5408\u91cf\uff08\u5bf9\u8c61\uff09\u3002<br>\u6807\u91cf\u66ff\u6362\uff0c\u5176\u5b9e\u6307\u7684\u5c31\u662f\u5c06\u805a\u5408\u91cf\u62c6\u5206\u4e3a\u4e00\u4e2a\u4e2a\u7684\u6807\u91cf\u653e\u5165\u6808\u4e2d\u3002<br>\u5728JIT\u9636\u6bb5\uff0c\u5982\u679c\u7ecf\u8fc7\u9003\u9038\u5206\u6790\uff0c\u53d1\u73b0\u4e00\u4e2a\u5bf9\u8c61\u4e0d\u4f1a\u88ab\u5916\u754c\u8bbf\u95ee\u7684\u8bdd\uff0c\u90a3\u4e48\u7ecf\u8fc7JIT\u4f18\u5316\uff0c\u5c31\u4f1a\u628a\u8fd9\u4e2a\u5bf9\u8c61\u62c6\u89e3\u6210\u82e5\u5e72\u4e2a\u5176\u4e2d\u5305\u542b\u7684\u82e5\u5e72\u4e2a\u6210\u5458\u53d8\u91cf\u6765\u4ee3\u66ff\u3002<\/p>\n\n\n\n<p>\u6848\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u6709\u4e00\u4e2a\u7c7bA\npublic class A {\n    public int a = 1;\n    public int b = 2;\n}\n\n\/\/ \u65b9\u6cd5getAB()\u4f7f\u7528\u7c7bA\u91cc\u9762\u7684AB\nprivate void getAB() {\n    A x = new A();\n    x.a;\n    x.b;\n}\n\n\/\/ JVM\u5728\u7f16\u8bd1\u65f6\u4f1a\u76f4\u63a5\u7f16\u8bd1\u6210\nprivate void getAB() {\n    a = 1;\n    b = 2;\n}\n\n\/\/ \u8fd9\u5c31\u662f\u6807\u91cf\u66ff\u6362<\/code><\/pre>\n\n\n\n<h5 class=\"wp-block-heading\">\u540c\u6b65\u9501\u6d88\u9664<\/h5>\n\n\n\n<p>\u540c\u6837\u57fa\u4e8e\u9003\u9038\u5206\u6790\u3001\u5f53\u524d\u9501\u7684\u53d8\u91cf\u4e0d\u4f1a\u53d1\u751f\u9003\u9038\u3001\u662f\u7ebf\u7a0b\u79c1\u6709\u7684\u5b8c\u5168\u6ca1\u6709\u5fc5\u8981\u52a0\u9501\u3002\u5728JIT\u7f16\u8bd1\u65f6\u671f\u5c31\u53ef\u4ee5\u5c06\u540c\u6b65\u9501\u53bb\u6389\uff0c\u4ee5\u51cf\u5c11\u52a0\u9501\u4e0e\u89e3\u9501\u9020\u6210\u7684\u8d44\u6e90\u5f00\u9500\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public class TestLockEliminate {\n    public static String getString(String s1, String s2) {\n        StringBuffer sb = new StringBuffer();\n        sb.append(s1);\n        sb.append(s2);\n        return sb.toString();\n    }\n\n    public static void main(String&#91;] args) {\n        long tsStart = System.currentTimeMillis();\n        for (int i = 0; i &lt; 100000000; i++) {\n            getString(\"TestLockEliminate \", \"Suffix\");\n        }\n        System.out.println(\"\u4e00\u5171\u8017\u8d39\uff1a \" + (System.currentTimeMillis() - tsStart) + \"ms\");\n    }\n}<\/code><\/pre>\n\n\n\n<p>\u5728\u5f00\u542f\u9003\u9038\u5206\u6790(-XX:+DoEscapedAnalysis )\u7684\u540c\u65f6\uff0c\u901a\u8fc7\u6539\u53d8\u540c\u6b65\u9501\u6d88\u9664(-XX:+EliminateLocks)\u7684\u53c2\u6570\u6765\u6d4b\u8bd5\u8fd0\u884c\u65f6\u95f4\u3002<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u8fd0\u884c\u65f6\u6570\u636e\u533a\u6982\u8ff0 JVM\u8fd0\u884c\u65f6\u6570\u636e\u533a\u89c4\u8303 \u5206\u914dJVM\u5185\u5b58\u7a7a\u95f4 \u65b9\u6cd5\u533a \u65b9\u6cd5\u533a\u5b58\u50a8\u4ec0\u4e48\u6570\u636e \u7c7b\u578b\u4fe1\u606f\u3001\u65b9\u6cd5\u4fe1\u606f\u3001 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25,85,86],"tags":[],"class_list":["post-1156","post","type-post","status-publish","format-standard","hentry","category-code","category-interview","category-java"],"_links":{"self":[{"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/posts\/1156","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/comments?post=1156"}],"version-history":[{"count":35,"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/posts\/1156\/revisions"}],"predecessor-version":[{"id":1598,"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/posts\/1156\/revisions\/1598"}],"wp:attachment":[{"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/media?parent=1156"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/categories?post=1156"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.spiceandwolf.com.cn\/index.php\/wp-json\/wp\/v2\/tags?post=1156"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}