{"id":10021080,"date":"2025-11-17T01:42:09","date_gmt":"2025-11-16T17:42:09","guid":{"rendered":"https:\/\/itmax.cn\/?p=10021080"},"modified":"2025-11-17T01:42:09","modified_gmt":"2025-11-16T17:42:09","slug":"%e6%b7%b1%e5%85%a5%e6%8e%a2%e7%b4%a2%e5%89%96%e6%9e%90-jvm-%e7%9a%84%e5%90%af%e5%8a%a8%e8%bf%87%e7%a8%8b","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10021080","title":{"rendered":"\u6df1\u5165\u63a2\u7d22\u5256\u6790 JVM \u7684\u542f\u52a8\u8fc7\u7a0b"},"content":{"rendered":"

\u4f60\u53ef\u66fe\u60f3\u8fc7\uff1a\u5f53\u4f60\u5728\u7ec8\u7aef\u91cc\u6572\u4e0b java<\/code>\uff0c\u5728 main<\/code> \u65b9\u6cd5\u771f\u6b63\u8fd0\u884c\u4e4b\u524d\uff0cJVM \u4e3a\u4e86\u201c\u521b\u9020\u4e00\u4e2a\u53ef\u8fd0\u884c\u4f60\u7684\u7a0b\u5e8f\u7684\u5b87\u5b99\u201d\uff0c\u5230\u5e95\u7ecf\u5386\u4e86\u54ea\u4e9b\u6b65\u9aa4\uff1f\u4ece\u53c2\u6570\u6821\u9a8c\u3001\u7cfb\u7edf\u8d44\u6e90\u63a2\u6d4b\uff0c\u5230\u9009\u62e9\u5783\u573e\u56de\u6536\u5668\uff0c\u518d\u5230\u7c7b\u7684\u52a0\u8f7d\u3001\u94fe\u63a5\u4e0e\u521d\u59cb\u5316\uff0c\u8fd9\u4e9b\u770b\u4e0d\u89c1\u7684\u8fc7\u7a0b\u51b3\u5b9a\u4e86\u5e94\u7528\u7684\u542f\u52a8\u4f53\u9a8c\u4e0e\u540e\u7eed\u6027\u80fd\u3002\u672c\u6587\u7528\u4e00\u4e2a\u6781\u7b80\u7684 HelloWorld \u8d2f\u7a7f\u5168\u7a0b\uff0c\u7ed3\u5408\u8be6\u7ec6\u65e5\u5fd7\uff0c\u4e00\u6b65\u6b65\u6d1e\u5bdf JVM \u7684\u542f\u52a8\u673a\u5236\uff0c\u5e2e\u4f60\u5728\u8c03\u8bd5\u548c\u6027\u80fd\u4f18\u5316\u65f6\u66f4\u6709\u6293\u624b\u3002<\/p>\n

1. \u6982\u89c8<\/h2>\n

\u5f53\u6211\u4eec\u8fd0\u884c\u4e00\u4e2a Java \u5e94\u7528\u65f6\uff0cJVM \u5728\u6211\u4eec\u7684\u4ee3\u7801\u771f\u6b63\u5f00\u59cb\u6267\u884c\u4e4b\u524d\uff0c\u4f1a\u5148\u5b8c\u6210\u4e00\u7cfb\u5217\u590d\u6742\u6b65\u9aa4\u3002\u672c\u6587\u5c06\u4ece\u6267\u884c java<\/code> \u547d\u4ee4\u7684\u90a3\u4e00\u523b\u5f00\u59cb\uff0c\u4e00\u76f4\u8d70\u5230\u5e94\u7528\u5c31\u7eea\u3002<\/p>\n

\u6211\u4eec\u4ee5\u4e00\u4e2a\u7b80\u5355\u7684 HelloWorld \u7a0b\u5e8f\u4e3a\u4f8b\uff0c\u62c6\u89e3\u6bcf\u4e00\u4e2a\u9636\u6bb5\u3002\u7406\u89e3\u8fd9\u4e9b\u5185\u90e8\u673a\u5236\u80fd\u663e\u8457\u63d0\u5347\u8c03\u8bd5\u4e0e\u6027\u80fd\u8c03\u4f18\u7684\u6548\u679c\u3002<\/p>\n

2. \u4ece java<\/code> \u547d\u4ee4\u5230 JVM \u542f\u52a8<\/h2>\n

\u5728 JVM \u6267\u884c\u4efb\u4f55\u4ee3\u7801\u4e4b\u524d\uff0c\u5b83\u9700\u8981\u5148\u542f\u52a8\u3001\u6821\u9a8c\u8f93\u5165\u5e76\u914d\u7f6e\u8fd0\u884c\u73af\u5883\u3002\u4e0b\u9762\u6309\u542f\u52a8\u987a\u5e8f\u8d70\u4e00\u904d\u65e9\u671f\u6d41\u7a0b\uff1a\u4ece\u8c03\u7528 java<\/code> \u547d\u4ee4\u5230\u521d\u59cb\u5316 JVM \u8fd0\u884c\u65f6\u3002<\/p>\n

2.1. java<\/code> \u547d\u4ee4\u4e0e\u521d\u59cb\u8c03\u7528<\/h3>\n

\u5f53\u6211\u4eec\u8fd0\u884c java<\/code> \u547d\u4ee4\u65f6\uff0cJVM \u542f\u52a8\u5e8f\u5217\u4f1a\u901a\u8fc7 JNI \u65b9\u6cd5 JNI_CreateJavaVM()<\/code> \u5f00\u59cb\u6267\u884c\u3002\u8be5\u65b9\u6cd5\u5b8c\u6210\u82e5\u5e72\u5173\u952e\u521d\u59cb\u5316\u4efb\u52a1\uff0c\u4e3a\u6267\u884c Java \u5e94\u7528\u51c6\u5907\u73af\u5883\u3002Java Native Interface\uff08JNI\uff09\u662f JVM \u4e0e\u539f\u751f\u7cfb\u7edf\u5e93\u4e4b\u95f4\u7684\u6865\u6881\uff0c\u4f7f Java \u4e0e\u5e73\u53f0\u7279\u6027\u53ef\u4ee5\u53cc\u5411\u901a\u4fe1\u3002<\/p>\n

\u672c\u6587\u5c06\u4f7f\u7528\u8be6\u7ec6\u65e5\u5fd7\u89c2\u5bdf JVM \u7684\u5185\u90e8\u8fd0\u4f5c\uff0c\u4f8b\u5982\uff1a<\/p>\n

java -Xlog:all=trace HelloWorldCopy<\/code><\/pre>\n
2.2. \u6821\u9a8c\u7528\u6237\u8f93\u5165<\/h3>\n
\u9996\u5148\uff0cJVM \u4f1a\u6821\u9a8c\u6211\u4eec\u4f20\u5165\u7684\u53c2\u6570\uff1a<\/p>\n
[0.006s][info][arguments] VM Arguments:\n[arguments] jvm_args: -Xlog:all=trace:file=helloworld.log \n[arguments] java_command: HelloWorld\n[arguments] java_class_path (initial): .\n[arguments] Launcher Type: SUN_STANDARD<\/code><\/pre>\n
JVM \u4f1a\u9a8c\u8bc1\u76ee\u6807\u53ef\u6267\u884c\u3001\u7c7b\u8def\u5f84\u4ee5\u53ca\u4efb\u4f55 JVM \u53c2\u6570\uff0c\u786e\u4fdd\u5b83\u4eec\u5728\u7ee7\u7eed\u6267\u884c\u524d\u90fd\u662f\u6709\u6548\u7684\u3002\u8fd9\u4e2a\u6b65\u9aa4\u80fd\u5c3d\u65e9\u6355\u83b7\u5f88\u591a\u5e38\u89c1\u914d\u7f6e\u9519\u8bef\uff0c\u907f\u514d\u540e\u7eed\u9636\u6bb5\u51fa\u73b0\u66f4\u96be\u5b9a\u4f4d\u7684\u95ee\u9898\u3002<\/p>\n
2.3. \u68c0\u6d4b\u7cfb\u7edf\u8d44\u6e90<\/h3>\n
\u63a5\u7740\uff0cJVM \u4f1a\u8bc6\u522b\u53ef\u7528\u7684\u7cfb\u7edf\u8d44\u6e90\uff0c\u4f8b\u5982\u5904\u7406\u5668\u6570\u91cf\u3001\u5185\u5b58\u5927\u5c0f\u4ee5\u53ca\u5173\u952e\u7cfb\u7edf\u670d\u52a1\uff1a<\/p>\n
[0.007s][debug][os       ] Process is running in a job with 20 active processors.\n[os       ] Initial active processor count set to 20\n[os       ] Process is running in a job with 20 active processors.\n[gc,heap  ]   Maximum heap size 4197875712\n[gc,heap  ]   Initial heap size 262367232\n[gc,heap  ]   Minimum heap size 6815736\n[os       ] Host Windows OS automatically schedules threads across all processor groups.\n[os       ] 20 logical processors found.<\/code><\/pre>\n
\u8fd9\u4e9b\u4fe1\u606f\u4f1a\u5f71\u54cd JVM \u7684\u4e00\u4e9b\u5185\u90e8\u51b3\u7b56\uff0c\u6bd4\u5982\u9ed8\u8ba4\u9009\u62e9\u54ea\u4e2a\u5783\u573e\u56de\u6536\u5668\u3002\u53ef\u7528 CPU \u6570\u548c\u603b\u5185\u5b58\u4f1a\u76f4\u63a5\u5f71\u54cd JVM \u7684\u542f\u53d1\u5f0f\u9009\u62e9\u3002\u4e0d\u8fc7\uff0c\u5927\u591a\u6570\u8bbe\u7f6e\u90fd\u53ef\u4ee5\u901a\u8fc7\u663e\u5f0f\u7684 JVM \u53c2\u6570\u8fdb\u884c\u8986\u76d6\u3002\u5728\u8fd9\u4e2a\u9636\u6bb5\uff0cJVM \u8fd8\u4f1a\u68c0\u67e5\u662f\u5426\u652f\u6301 Native Memory Tracking\uff0c\u5e76\u9a8c\u8bc1\u5b83\u53ef\u80fd\u4f9d\u8d56\u7684\u5404\u7c7b\u64cd\u4f5c\u7cfb\u7edf\u5de5\u5177\u7684\u53ef\u7528\u6027\u3002<\/p>\n
2.4. \u73af\u5883\u51c6\u5907<\/h3>\n
\u968f\u540e\uff0cJVM \u4f1a\u751f\u6210 HotSpot \u6027\u80fd\u6570\u636e\u3002\u8fd9\u4e9b\u6570\u636e\u4f1a\u88ab JConsole\u3001VisualVM \u7b49\u5de5\u5177\u7528\u4e8e\u68c0\u67e5\u548c\u5206\u6790 JVM\uff1a<\/p>\n
[perf,datacreation] name = sun.rt._sync_Inflations, dtype = 11, variability = 2, units = 4, dsize = 8, vlen = 0, pad_length = 4, size = 56, on_c_heap = FALSE, address = 0x000001f3085f0020, data address = 0x000001f3085f0050<\/code><\/pre>\n
\u8fd9\u7c7b\u6027\u80fd\u6570\u636e\u901a\u5e38\u5b58\u50a8\u5728\u7cfb\u7edf\u7684 \/tmp<\/code> \u76ee\u5f55\u4e0b\uff0c\u5e76\u4f1a\u5728\u542f\u52a8\u9636\u6bb5\u7684\u4e00\u6bb5\u65f6\u95f4\u91cc\u6301\u7eed\u751f\u6210\uff0c\u4e0e\u5176\u4ed6\u521d\u59cb\u5316\u4efb\u52a1\u5e76\u884c\u8fdb\u884c\u3002<\/p>\n
3. \u52a0\u8f7d\u3001\u94fe\u63a5\u4e0e\u521d\u59cb\u5316<\/h2>\n
\u5f53 JVM \u73af\u5883\u5c31\u7eea\u540e\uff0c\u5b83\u4f1a\u5f00\u59cb\u4e3a\u6211\u4eec\u7684\u7a0b\u5e8f\u6267\u884c\u505a\u51c6\u5907\u3002<\/p>\n
3.1. \u9009\u62e9\u5783\u573e\u56de\u6536\u5668<\/h3>\n
\u5728 JVM \u5185\u90e8\uff0c\u4e00\u4e2a\u5173\u952e\u6b65\u9aa4\u662f\u9009\u62e9\u5783\u573e\u56de\u6536\u5668\uff08GC\uff09\u3002\u622a\u81f3 JDK 23\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b JVM \u4f1a\u9009\u62e9 G1 GC\uff0c\u9664\u975e\u7cfb\u7edf\u53ef\u7528\u5185\u5b58\u5c11\u4e8e 1792MB \u548c\/\u6216\u4ec5\u6709\u5355\u5904\u7406\u5668\uff1a<\/p>\n
[gc               ] Using G1\n[gc,heap,coops    ] Trying to allocate at address 0x0000000705c00000 heap of size 0xfa400000\n[os               ] VirtualAlloc(0x0000000705c00000, 4198498304, 2000, 4) returned 0x0000000705c00000.\n[os,map           ] Reserved [0x0000000705c00000 - 0x0000000800000000), (4198498304 bytes)\n[gc,heap,coops    ] Heap address: 0x0000000705c00000, size: 4004 MB, Compressed Oops mode: Zero based, Oop shift amount: 3\n[pagesize         ] Heap:  min=8M max=4004M base=0x0000000705c00000 size=4004M page_size=4K<\/code><\/pre>\n
\u5f53\u7136\uff0c\u6211\u4eec\u4e5f\u53ef\u4ee5\u9009\u62e9\u5176\u5b83 GC\uff1a\u5982 Parallel GC\u3001ZGC \u7b49\uff0c\u5177\u4f53\u53ef\u7528\u4e0e\u9ed8\u8ba4\u7b56\u7565\u4f9d\u4e0d\u540c JDK \u7248\u672c\u4e0e\u53d1\u884c\u7248\u800c\u5f02\u3002<\/p>\n
3.2. \u52a0\u8f7d CDS\uff08\u7c7b\u6570\u636e\u5171\u4eab\uff09<\/h3>\n
\u6b64\u65f6\uff0cJVM \u4f1a\u5f00\u59cb\u5bfb\u627e\u8fdb\u4e00\u6b65\u7684\u4f18\u5316\u673a\u4f1a\u3002CDS \u662f\u4e00\u7ec4\u5df2\u7ecf\u7ecf\u8fc7\u9884\u5904\u7406\u7684\u7c7b\u6587\u4ef6\u5f52\u6863\uff0c\u53ef\u4ee5\u6539\u5584 JVM \u7684\u542f\u52a8\u6027\u80fd\uff1a<\/p>\n
[cds] trying to map [Java home]\/lib\/server\/classes.jsa\n[cds] Opened archive [Java home]\/lib\/server\/classes.jsa<\/code><\/pre>\n
\u4e0d\u8fc7\uff0cCDS \u6b63\u5728\u88ab Project Leyden \u4e2d\u7684 AOT\uff08\u63d0\u524d\uff09\u673a\u5236\u9010\u6b65\u66ff\u4ee3\uff0c\u540e\u6587\u4f1a\u7ee7\u7eed\u8ba8\u8bba\u3002<\/p>\n
3.3. \u521b\u5efa\u65b9\u6cd5\u533a<\/h3>\n
JVM \u968f\u540e\u4f1a\u521b\u5efa\u201c\u65b9\u6cd5\u533a\u201d\uff0c\u8fd9\u662f\u4e00\u4e2a\u7528\u4e8e\u5b58\u50a8\u7c7b\u6570\u636e\u7684\u7279\u6b8a\u79bb\u5806\u5185\u5b58\u533a\u57df\u3002\u5728 HotSpot \u4e2d\uff0c\u8fd9\u4e00\u533a\u57df\u88ab\u79f0\u4e3a metaspace\u3002\u5f53\u5173\u8054\u7684\u7c7b\u52a0\u8f7d\u5668\u4e0d\u518d\u53ef\u8fbe\u65f6\uff0c\u5b58\u50a8\u4e8e\u6b64\u7684\u7c7b\u6570\u636e\u4e5f\u4f1a\u88ab\u79fb\u9664\uff1a<\/p>\n
[metaspace,map    ] Trying anywhere...\n[metaspace,map    ] Mapped at 0x000001f32b000000<\/code><\/pre>\n
\u867d\u7136\u65b9\u6cd5\u533a\u4e0d\u5728\u5806\u4e2d\uff0c\u4f46\u5b83\u4ecd\u7531 GC \u7ba1\u7406\u3002<\/p>\n
3.4. \u7c7b\u52a0\u8f7d<\/h3>\n
\u7c7b\u52a0\u8f7d\u5305\u542b\u4e09\u4e2a\u6b65\u9aa4\uff1a\u5b9a\u4f4d\u4e8c\u8fdb\u5236\u8868\u793a\u3001\u6839\u636e\u5176\u6d3e\u751f\u51fa\u7c7b\u3001\u5e76\u5c06\u5176\u52a0\u8f7d\u5230\u65b9\u6cd5\u533a\u3002\u6b63\u662f\u8fd9\u79cd\u52a8\u6001\u52a0\u8f7d\u80fd\u529b\uff0c\u8ba9 Spring\u3001Mockito \u7b49\u6846\u67b6\u53ef\u4ee5\u5728\u8fd0\u884c\u671f\u6309\u9700\u751f\u6210\u5e76\u52a0\u8f7d\u7c7b\u3002<\/p>\n
\u7c7b\u52a0\u8f7d\u6709\u4e24\u79cd\u65b9\u5f0f\uff1a\u5f15\u5bfc\u7c7b\u52a0\u8f7d\u5668\uff08bootstrap class loader\uff09\u6216\u81ea\u5b9a\u4e49\u7c7b\u52a0\u8f7d\u5668\u3002\u4e0b\u9762\u501f\u52a9\u4e00\u4e2a\u7b80\u5355\u7684 HelloWorld<\/code> \u7c7b\uff0c\u770b\u770b JVM \u9996\u5148\u4f1a\u505a\u4ec0\u4e48\uff1a<\/p>\n
public class HelloWorld extends Object {\n    public static void main(String[] args) {\n        System.out.println("Hello World!");\n    }\n}<\/code><\/pre>\n
JVM \u4f1a\u4f18\u5148\u52a0\u8f7d java.lang.Object<\/code> \u53ca\u5176\u4f9d\u8d56\u3002\u7c7b\u5728\u521d\u6b21\u52a0\u8f7d\u65f6\u5927\u591a\u5904\u4e8e\u201c\u534a\u9690\u85cf\u201d\u7684\u72b6\u6001\uff0c\u4ee5\u4fbf\u8fdb\u884c\u5fc5\u8981\u7684\u9a8c\u8bc1\u4e0e\u6574\u7406\u5de5\u4f5c\u3002<\/p>\n
\u518d\u770b\u4e0b java.lang.Object<\/code> \u7684\u65b9\u6cd5\uff1a<\/p>\n
public class Object {\n    public final native Class<?> getClass()\n    public String toString()\n    public boolean equals(Object obj)\n}<\/code><\/pre>\n
\u8fd9\u4e9b\u65b9\u6cd5\u5206\u522b\u5f15\u7528\u4e86 java.lang.Class<\/code> \u4e0e java.lang.String<\/code>\uff0c\u56e0\u6b64\u5b83\u4eec\u4e5f\u9700\u8981\u5148\u884c\u52a0\u8f7d\u3002JVM \u91c7\u7528\u201c\u6309\u9700\u52a0\u8f7d\u201d\u7684\u7b56\u7565\uff0c\u4ec5\u5728\u7c7b\u88ab\u5b9e\u9645\u5f15\u7528\u65f6\u624d\u52a0\u8f7d\u3002\u4e0d\u8fc7\uff0c\u4e0a\u8ff0\u8fd9\u4e9b\u5bf9 JVM \u81f3\u5173\u91cd\u8981\u7684\u7c7b\u4f1a\u88ab\u201c\u62a2\u5148\u52a0\u8f7d\u201d\u3002\u5728\u4e00\u4e2a\u7b80\u5355\u7684 HelloWorld \u7a0b\u5e8f\u91cc\uff0c\u7531 JNI_CreateJavaVM()<\/code> \u521d\u59cb\u5316\u7684\u5f15\u5bfc\u7c7b\u52a0\u8f7d\u5668\u8d1f\u8d23\u6240\u6709\u7684\u7c7b\u52a0\u8f7d\u5de5\u4f5c\u3002<\/p>\n
3.5. \u7c7b\u94fe\u63a5<\/h3>\n
\u7c7b\u94fe\u63a5\u53ef\u4ee5\u62c6\u5206\u4e3a\u9a8c\u8bc1\uff08Verification\uff09\u3001\u51c6\u5907\uff08Preparation\uff09\u4e0e\u89e3\u6790\uff08Resolution\uff09\uff0c\u5176\u53d1\u751f\u987a\u5e8f\u5e76\u4e0d\u56fa\u5b9a\uff1a\u89e3\u6790\u53ef\u80fd\u53d1\u751f\u5728\u9a8c\u8bc1\u4e4b\u524d\uff0c\u4e5f\u53ef\u80fd\u5728\u7c7b\u521d\u59cb\u5316\u4e4b\u540e\u3002\u9a8c\u8bc1\u786e\u4fdd\u7c7b\u7ed3\u6784\u6b63\u786e\uff1a<\/p>\n
[class,init] Start class verification for: HelloWorld\n[verification] Verifying class HelloWorld with new format\n[verification] Verifying method HelloWorld.<init>()V<\/code><\/pre>\n
\u4f4d\u4e8e CDS \u4e2d\u7684\u7c7b\u5df2\u7ecf\u8fc7\u9a8c\u8bc1\uff0c\u56e0\u6b64\u4f1a\u8df3\u8fc7\u8be5\u6b65\u9aa4\uff0c\u4ece\u800c\u63d0\u5347\u542f\u52a8\u6027\u80fd\u3002\u8fd9\u662f CDS \u7684\u91cd\u8981\u6536\u76ca\u4e4b\u4e00\u3002\u5728\u201c\u51c6\u5907\u201d\u9636\u6bb5\uff0cJVM \u4f1a\u7528\u9ed8\u8ba4\u503c\u521d\u59cb\u5316\u9759\u6001\u5b57\u6bb5\uff0c\u6ca1\u6709\u663e\u5f0f\u521d\u59cb\u5316\u5668\u7684\u9759\u6001\u53d8\u91cf\u4f1a\u81ea\u52a8\u83b7\u5f97\u9ed8\u8ba4\u503c\u3002<\/p>\n
\u5728\u201c\u89e3\u6790\u201d\u9636\u6bb5\uff0cJVM \u4f1a\u89e3\u6790\u5e38\u91cf\u6c60\uff08Constant Pool\uff09\u4e2d\u7684\u7b26\u53f7\u5f15\u7528\u3002\u5e38\u91cf\u6c60\u4fdd\u5b58\u4e86\u7c7b\u7684\u6240\u6709\u7b26\u53f7\u5f15\u7528\uff0cJVM \u5fc5\u987b\u5148\u5c06\u5176\u89e3\u6790\u4e3a\u771f\u5b9e\u7684\u5185\u5b58\u5f15\u7528\uff0c\u624d\u80fd\u6267\u884c\u76f8\u5173\u6307\u4ee4\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 javap<\/code> \u6765\u89c2\u5bdf\uff1a<\/p>\n
javap -verbose HelloWorldCopy<\/code><\/pre>\n
\u8fd9\u5c06\u663e\u793a\u5e38\u91cf\u6c60\u7684\u5185\u5bb9\uff1a<\/p>\n
Constant pool:\n   #1 = Methodref          #2.#3          \/\/ java\/lang\/Object."<init>":()V\n   #2 = Class              #4             \/\/ java\/lang\/Object\n   #3 = NameAndType        #5:#6          \/\/ "<init>":()V\n   #7 = Fieldref           #8.#9          \/\/ java\/lang\/System.out:Ljava\/io\/PrintStream;\n  #13 = String             #14            \/\/ Hello World<\/code><\/pre>\n
\u6784\u9020\u5668\u7684\u5b57\u8282\u7801\u5e76\u4e0d\u76f4\u63a5\u5305\u542b\u5730\u5740\u3002\u5b83\u5f15\u7528\u5e38\u91cf\u6c60\u4e2d\u7684\u7b26\u53f7\u9879\uff08\u4f8b\u5982 #1<\/code>\uff09\uff0c\u8fd9\u4e9b\u6761\u76ee\u63cf\u8ff0\u4e86\u65b9\u6cd5\u6216\u5b57\u6bb5\u3002\u89e3\u6790\u9636\u6bb5\u4f1a\u5c06\u8fd9\u4e9b\u7b26\u53f7\u9879\u8f6c\u4e3a\u53ef\u6267\u884c\u7684\u771f\u5b9e\u5185\u5b58\u5f15\u7528\uff1a<\/p>\n
public HelloWorld();\n  descriptor: ()V\n  flags: (0x0001) ACC_PUBLIC\n  Code:\n    stack=1, locals=1, args_size=1\n       0: aload_0\n       1: invokespecial #1                  \/\/ Method java\/lang\/Object."<init>":()V\n       4: return\n  LineNumberTable:\n    line 2: 0\n    line 4: 4<\/code><\/pre>\n
\u7b2c 1 \u884c\u7684 invokespecial<\/code> \u6307\u4ee4\u5f15\u7528\u4e86\u5e38\u91cf\u6c60\u6761\u76ee #1<\/code>\uff0c\u5176\u4e2d\u5305\u542b\u94fe\u63a5\u5230 java.lang.Object<\/code> \u6784\u9020\u5668\u6240\u9700\u7684\u4fe1\u606f\u3002<init><\/code> \u8868\u793a\u8fd9\u662f\u7531 javac<\/code> \u4e3a\u6bcf\u4e2a\u6784\u9020\u5668\u81ea\u52a8\u751f\u6210\u7684\u7279\u6b8a\u65b9\u6cd5\u3002JVM \u91c7\u7528\u201c\u5ef6\u8fdf\u89e3\u6790\u201d\uff0c\u53ea\u6709\u5728\u5c1d\u8bd5\u6267\u884c\u7c7b\u4e2d\u7684\u67d0\u6761\u6307\u4ee4\u65f6\u624d\u89e6\u53d1\u89e3\u6790\uff1b\u5e76\u975e\u6240\u6709\u5df2\u52a0\u8f7d\u7684\u7c7b\u90fd\u4f1a\u5b9e\u9645\u6267\u884c\u5176\u6307\u4ee4\u3002<\/p>\n
3.6. \u7c7b\u521d\u59cb\u5316<\/h3>\n
\u7c7b\u521d\u59cb\u5316\u4f1a\u4e3a\u9759\u6001\u5b57\u6bb5\u8d4b\u503c\u5e76\u6267\u884c\u9759\u6001\u521d\u59cb\u5316\u5668\uff0c\u8fd9\u4e0e\u6211\u4eec\u8c03\u7528\u6784\u9020\u5668\u7684\u5b9e\u4f8b\u521d\u59cb\u5316\u4e0d\u540c\u3002\u8be5\u8fc7\u7a0b\u7531 javac<\/code> \u81ea\u52a8\u751f\u6210\u7684\u7279\u6b8a\u65b9\u6cd5 clinit<\/code> \u8d1f\u8d23\u3002<\/p>\n
4. \u4f18\u5316 JVM \u542f\u52a8\u6027\u80fd<\/h2>\n
\u5c3d\u7ba1 JVM \u7684\u542f\u52a8\u5df2\u7ecf\u5f88\u9ad8\u6548\uff0c\u4f46\u4ecd\u6709\u63d0\u5347\u7a7a\u95f4\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u65b9\u5411\u3002<\/p>\n
4.1. \u7c7b\u52a0\u8f7d\u7684\u5f71\u54cd<\/h3>\n
\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u7cfb\u7edf\u7684 time<\/code> \u5de5\u5177\u6765\u5ea6\u91cf JVM \u542f\u52a8\u3001\u52a0\u8f7d\u7c7b\u3001\u94fe\u63a5\u5e76\u6267\u884c\u8fd9\u4e2a\u7b80\u5355\u7a0b\u5e8f\u7684\u603b\u8017\u65f6\uff1a<\/p>\n
time java HelloWorldCopy<\/code><\/pre>\n
\u8be5\u5de5\u5177\u4f1a\u6d4b\u91cf\u4ece JVM \u8fdb\u7a0b\u542f\u52a8\u5230\u9000\u51fa\u7684\u6302\u949f\u65f6\u95f4\uff0c\u5305\u542b\u7c7b\u52a0\u8f7d\u3001\u94fe\u63a5\u3001JIT \u9884\u70ed\u4e0e\u7a0b\u5e8f\u6267\u884c\u2014\u2014\u4e0d\u4ec5\u4ec5\u662f\u7528\u6237\u4ee3\u7801\u3002\u5bf9\u4e8e HelloWorld\uff0cJVM \u5728\u542f\u52a8\u671f\u95f4\u901a\u5e38\u4f1a\u52a0\u8f7d\u7ea6 400\uff5e450 \u4e2a\u7c7b\u3002\u5728\u73b0\u4ee3\u786c\u4ef6\u4e0a\uff0c\u5373\u4fbf\u5f00\u542f\u5197\u957f\u65e5\u5fd7\uff0c\u6574\u4e2a\u8fc7\u7a0b\u4e5f\u5927\u7ea6\u5728 60 \u6beb\u79d2\u5de6\u53f3\u5b8c\u6210\u3002<\/p>\n
4.2. Project Leyden<\/h3>\n
Project Leyden \u7684\u76ee\u6807\u662f\u51cf\u5c11\u542f\u52a8\u65f6\u95f4\u3001\u8fbe\u5230\u5cf0\u503c\u6027\u80fd\u7684\u65f6\u95f4\u4ee5\u53ca\u5185\u5b58\u5360\u7528\u3002JDK 24 \u5f15\u5165\u4e86 JEP 483\uff1aAhead-of-Time Class Loading and Linking\uff08\u63d0\u524d\u7c7b\u52a0\u8f7d\u4e0e\u94fe\u63a5\uff09\uff0c\u5c06\u8fd9\u4e9b\u64cd\u4f5c\u4ece\u542f\u52a8\u65f6\u524d\u79fb\u81f3 AOT \u9636\u6bb5\u3002<\/p>\n
\u8be5\u7279\u6027\u4f1a\u5728\u201c\u8bad\u7ec3\u8fd0\u884c\u201d\u4e2d\u8bb0\u5f55 JVM \u7684\u884c\u4e3a\uff0c\u5c06\u5176\u5b58\u5165\u7f13\u5b58\uff0c\u5e76\u5728\u540e\u7eed\u542f\u52a8\u65f6\u4ece\u7f13\u5b58\u52a0\u8f7d\u3002\u8fd9\u5c06\u53d6\u4ee3\u539f\u5148\u7684 CDS \u6982\u5ff5\uff0c\u5e76\u6700\u7ec8\u4ee5 AOT \u7684\u66f4\u5e7f\u6cdb\u80fd\u529b\u6765\u7edf\u4e00\u8868\u8fbe\u3002<\/p>\n
4.3. JVM \u53c2\u6570\u4e0e\u8c03\u4f18<\/h3>\n
\u867d\u7136\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u9759\u6001\u5b57\u6bb5\u4e0e\u521d\u59cb\u5316\u5668\u5728\u67d0\u4e9b\u573a\u666f\u4e2d\u4f18\u5316\u542f\u52a8\u6027\u80fd\uff0c\u4f46\u5e94\u8c28\u614e\u5bf9\u5f85\u3002\u4e3a\u4e86\u5c06\u884c\u4e3a\u632a\u5230\u7c7b\u52a0\u8f7d\u9636\u6bb5\u800c\u8fdb\u884c\u91cd\u6784\uff0c\u5f80\u5f80\u5f88\u96be\u83b7\u5f97\u53ef\u6d4b\u91cf\u7684\u6536\u76ca\u2014\u2014\u7279\u522b\u662f\u8003\u8651\u5230\u8fd0\u884c\u65f6\u7684\u5927\u90e8\u5206\u4ee3\u7801\u6765\u81ea\u4f9d\u8d56\u5e93\u800c\u975e\u6211\u4eec\u81ea\u5df1\u7684\u5e94\u7528\u3002<\/p>\n
5. \u7ed3\u8bba<\/h2>\n
\u672c\u6587\u4ece\u6821\u9a8c\u7528\u6237\u8f93\u5165\u3001\u68c0\u6d4b\u7cfb\u7edf\u8d44\u6e90\uff0c\u5230\u7c7b\u7684\u52a0\u8f7d\u3001\u94fe\u63a5\u4e0e\u521d\u59cb\u5316\uff0c\u7cfb\u7edf\u5730\u68b3\u7406\u4e86 JVM \u5728\u542f\u52a8\u9636\u6bb5\u7ecf\u5386\u7684\u590d\u6742\u6d41\u7a0b\u3002\u5373\u4fbf\u662f\u4e00\u4e2a\u7b80\u5355\u7684 HelloWorld\uff0cJVM \u4e5f\u4f1a\u5728\u6267\u884c\u4ee3\u7801\u4e4b\u524d\u6784\u5efa\u8d77\u5b8c\u6574\u7684\u8fd0\u884c\u73af\u5883\uff0c\u52a0\u8f7d\u6570\u767e\u4e2a\u7c7b\u3002<\/p>\n
\u968f\u7740 Project Leyden \u7b49\u6539\u8fdb\uff08\u4f8b\u5982 AOT\uff09\u7684\u5230\u6765\uff0cJVM \u7684\u542f\u52a8\u6027\u80fd\u8fd8\u5c06\u8fdb\u4e00\u6b65\u63d0\u5347\u3002<\/p>\n
\u66f4\u591a\u76f8\u5173\u6280\u672f\u5e72\u8d27\u5206\u4eab\u53ef\u4ee5\u5173\u6ce8\u8fd9\u4e2aJava\u4e13\u9898<\/a><\/p><\/blockquote>\n
https:\/\/segmentfault.com\/a\/1190000047403401<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
\u4f60\u53ef\u66fe\u60f3\u8fc7\uff1a\u5f53\u4f60\u5728\u7ec8\u7aef\u91cc\u6572\u4e0b java\uff0c\u5728 main \u65b9\u6cd5\u771f\u6b63\u8fd0\u884c\u4e4b\u524d\uff0cJVM \u4e3a\u4e86\u201c\u521b\u9020\u4e00\u4e2a\u53ef\u8fd0\u884c\u4f60\u7684\u7a0b\u5e8f\u7684 […]<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[4],"tags":[],"class_list":["post-10021080","post","type-post","status-publish","format-standard","hentry","category-share"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts\/10021080","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=10021080"}],"version-history":[{"count":0,"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts\/10021080\/revisions"}],"wp:attachment":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10021080"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10021080"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10021080"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}