\u8fd9\u662f\u4e00\u4e2a\u65b0\u7684\u5de5\u7a0b\u3002\u6211\u4eec\u6709\u4e00\u4e2a\u63a5\u53e3\u53eb `MyInterface`\uff0c\u91cc\u9762\u5b9a\u4e49\u4e86\u4e09\u4e2a\u65b9\u6cd5\uff1a`func1()`\u3001`func2()` \u548c `func3()`\u3002<\/p>\n\n\n\n
\u73b0\u5728\u6211\u4eec\u6709\u4e00\u4e2a\u9700\u6c42\uff1a\u6bcf\u4e2a\u65b9\u6cd5\u88ab\u8c03\u7528\u65f6\uff0c\u90fd\u8981\u6253\u5370\u51fa\u81ea\u5df1\u7684\u65b9\u6cd5\u540d\u3002\u6700\u7b80\u5355\u7684\u505a\u6cd5\u662f\u5199\u4e00\u4e2a\u5b9e\u73b0\u7c7b `NameImpl`\uff1a<\/p>\n\n\n\n
```java
public class NameImpl implements MyInterface {
@Override
public void func1() {
System.out.println(\"func1\");
}<\/p>\n\n\n\n
@Override
public void func2() {
System.out.println(\"func2\");
}<\/p>\n\n\n\n
@Override
public void func3() {
System.out.println(\"func3\");
}
}
```<\/p>\n\n\n\n
\u4f46\u5f88\u5feb\u9700\u6c42\u53d8\u4e86\uff1a\u4e0d\u4ec5\u8981\u6253\u5370\u65b9\u6cd5\u540d\uff0c\u8fd8\u8981\u6253\u5370\u65b9\u6cd5\u540d\u7684\u957f\u5ea6\u3002\u4e8e\u662f\u6211\u4eec\u518d\u5199\u4e00\u4e2a\u65b0\u7c7b `NameAndLengthImpl`\uff0c\u540c\u6837\u5b9e\u73b0 `MyInterface`\uff0c\u4f46\u5185\u90e8\u903b\u8f91\u53d8\u6210\u4e86\uff1a<\/p>\n\n\n\n
public class NameAndLengthImpl implements MyInterface {\n\n @Override\n public void func1() {\n String methodName = \"func1\";\n System.out.println(methodName);\n System.out.println(methodName.length());\n }\n\n @Override\n public void func2() {\n String methodName = \"func2\";\n System.out.println(methodName);\n System.out.println(methodName.length());\n }\n\n @Override\n public void func3() {\n String methodName = \"func3\";\n System.out.println(methodName);\n System.out.println(methodName.length());\n }\n}<\/code><\/pre>\n\n\n\n\u95ee\u9898\u6765\u4e86\uff1a\u5982\u679c\u6211\u4eec\u9700\u8981\u4e3a\u4e0d\u540c\u7684\u884c\u4e3a\uff08\u6bd4\u5982\u6253\u5370\u65f6\u95f4\u3001\u52a0\u65e5\u5fd7\u3001\u8ba1\u6570\u7b49\uff09\u521b\u5efa\u591a\u4e2a\u5b9e\u73b0\u7c7b\uff0c\u4ee3\u7801\u4f1a\u5927\u91cf\u91cd\u590d\uff0c\u4e14\u65e0\u6cd5\u52a8\u6001\u6269\u5c55\u3002\u6211\u4eec\u80fd\u5426**\u5728\u8fd0\u884c\u65f6\u52a8\u6001\u751f\u6210\u7c7b**\uff1f<\/p>\n\n\n\n
\u7b54\u6848\u662f\u53ef\u4ee5\u7684\u3002Java \u5141\u8bb8\u6211\u4eec\u5728\u7a0b\u5e8f\u8fd0\u884c\u671f\u95f4\u751f\u6210 Java \u6e90\u7801\u6587\u4ef6\uff0c\u7f16\u8bd1\u6210 `.class` \u6587\u4ef6\uff0c\u5e76\u52a0\u8f7d\u5230 JVM \u4e2d\u4f7f\u7528\u3002<\/p>\n\n\n\n
\u4e3a\u6b64\uff0c\u6211\u4eec\u521b\u5efa\u4e00\u4e2a\u5de5\u5382\u7c7b `MyInterfaceFactory`\uff0c\u7528\u6765\u4e13\u95e8\u751f\u6210\u5b9e\u73b0\u4e86 `MyInterface` \u7684\u4ee3\u7406\u7c7b\u3002<\/p>\n\n\n\n
\u7b2c\u4e00\u6b65\uff1a\u751f\u6210 Java \u6e90\u6587\u4ef6<\/p>\n\n\n\n
\u6211\u4eec\u5199\u4e00\u4e2a\u65b9\u6cd5 `createJavaFile()`\uff0c\u5b83\u5c06\u62fc\u63a5\u51fa\u4e00\u4e2a\u5b8c\u6574\u7684 Java \u7c7b\u6e90\u7801\u5b57\u7b26\u4e32\uff0c\u5e76\u5199\u5165\u6587\u4ef6\uff1a<\/p>\n\n\n\n
public class MyInterfaceFactory {\n\n public static File createJavaFile() throws IOException {\n String context = \"package tech.insight.proxy;\\n\" +\n \"\\n\" +\n \"public class NameImpl implements MyInterface {\\n\" +\n \" @Override\\n\" +\n \" public void func1() {\\n\" +\n \" System.out.println(\\\"func1\\\");\\n\" +\n \" }\\n\" +\n \"\\n\" +\n \" @Override\\n\" +\n \" public void func2() {\\n\" +\n \" System.out.println(\\\"func2\\\");\\n\" +\n \" }\\n\" +\n \"\\n\" +\n \" @Override\\n\" +\n \" public void func3() {\\n\" +\n \" System.out.println(\\\"func3\\\");\\n\" +\n \" }\\n\" +\n \"}\\n\";\n\n File javaFile = new File(\"NameImpl.java\");\n Files.write(javaFile.toPath(), context);\n return javaFile;\n }\n\n public static void main(String[] args) throw Exception {\n createJavaFile();\n }\n}<\/code><\/pre>\n\n\n\n\u6267\u884c\u540e\uff0c\u786e\u5b9e\u53e6\u5916\u751f\u6210\u4e86\u4e00\u4e2a `NameImpl.java\u7684\u6587\u4ef6\u3002java\u865a\u62df\u673a\u4e0d\u80fd\u76f4\u63a5\u5bf9\u5b8c\u6210<\/p>\n\n\n\n
\u7b2c\u4e8c\u6b65\uff1a\u7f16\u8bd1 Java \u6587\u4ef6<\/p>\n\n\n\n
Java \u63d0\u4f9b\u4e86 `JavaCompiler` \u5de5\u5177\uff0c\u53ef\u4ee5\u5728\u8fd0\u884c\u65f6\u52a8\u6001\u7f16\u8bd1 Java \u6587\u4ef6\uff1a\u4f60\u53ef\u4ee5\u770b\u770bCompiler\u6587\u4ef6<\/p>\n\n\n\n
```java
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
int result = compiler.run(null, null, null, javaFile.getPath());
```<\/p>\n\n\n\n
\u6211\u4eec\u5c06\u7f16\u8bd1\u540e\u7684 `.class` \u6587\u4ef6\u653e\u5728\u9879\u76ee\u7684 `target\/classes` \u76ee\u5f55\u4e0b\uff0c\u786e\u4fdd\u7c7b\u8def\u5f84\u53ef\u8bbf\u95ee\u3002<\/p>\n\n\n\n
Compiler.compile(javaFile);
\u5f97\u5230\u4e86.class\u6587\u4ef6<\/strong><\/p>\n\n\n\n\u63a5\u7740\u4f5c\u8005\u901a\u8fc7\u81ea\u8bbegetClassName\uff08\uff09{<\/p>\n\n\n\n
return \"MyInterface$proxy\" + count.incrementAndGet();<\/p>\n\n\n\n
}<\/p>\n\n\n\n
\u8fd9\u6837\u83b7\u5f97\u67d0\u4e9b\u5185\u5bb9\uff0c\u5982\u4f55\u8fdb\u4e00\u6b65\u52a8\u6001\u5462\uff1f<\/p>\n\n\n\n
functionBody(Stirng methodName){<\/p>\n\n\n\n
return \"System.out .println\" +methodName +\"\\\");\";<\/p>\n\n\n\n
}<\/p>\n\n\n\n
\u8fd9\u6837\u6211\u4eec\u53ef\u4ee5\u8fdb\u4e00\u6b65<\/p>\n\n\n\n
String func1Body = functionBody(\"func1\");\nString func2Body = functionBody(\"func2\");\nString func3Body = functionBody(\"func3\");\nString context = \"package tech.insight.proxy;\\n\" +\n \"\\n\" +\n \"public class \" + className + \" implements MyInterface {\\n\" +\n \" @Override\\n\" +\n \" public void func1() {\\n\" +\n \" \" + func1Body + \"\\n\" +\n \" }\\n\" +\n \"\\n\" +\n \" @Override\\n\" +\n \" public void func2() {\\n\" +\n \" \" + func2Body + \"\\n\" +\n \" }\\n\" +\n \"\\n\" +\n \" @Override\\n\" +\n \" public void func3() {\\n\" +\n \" \" + func3Body + \"\\n\" +\n \" }\\n\" +\n \"}\";<\/code><\/pre>\n\n\n\n\u7b2c\u4e09\u6b65\uff1a\u52a0\u8f7d\u5e76\u5b9e\u4f8b\u5316\u7c7b<\/p>\n\n\n\n
private static MyInterface newInstance(String className) throws Exception {\n Class<?> aClass = MyInterfaceFactory.class.getClassLoader().loadClass(className);\n Constructor<?> constructor = aClass.getConstructor();\n MyInterface proxy = (MyInterface) constructor.newInstance();\n return proxy;\n}\n\npublic static MyInterface createProxyObject() throws Exception {\n String className = getClassName();\n File javaFile = createJavaFile(className);\n Compiler.compile(javaFile);\n return newInstance(\"tech.insight.proxy.\" + className);\n}<\/code><\/pre>\n\n\n\n\u521b\u5efa\u4e00\u4e2amain\u65b9\u6cd5\uff0c\u628a\u4e0a\u9762\u7684\u6240\u6709\u6682\u65f6\u7edf\u7edf\u79c1\u6709\uff0c\u521b\u5efa\u4e86\u672c\u6765\u5728\u865a\u62df\u673a\u4e2d\u7684\u6ca1\u6709\u7684\u7c7b\uff1b<\/p>\n\n\n\n
public class Main {<\/p>\n\n\n\n
public static void main(String[] args) throws Exception {
MyInterface proxyObject = MyInterfaceFactory.createProxyObject();
proxyObject.func1();
proxyObject.func2();
proxyObject.func3();
}
}\u4f7f\u7528\u7c7b\u52a0\u8f7d\u5668\u5c06\u7f16\u8bd1\u597d\u7684\u5b57\u8282\u7801\u52a0\u8f7d\u8fdb\u865a\u62df\u673a\uff1a<\/p>\n\n\n\n
```java
URLClassLoader classLoader = URLClassLoader.newInstance(new URL[]{new File(\"target\/classes\").toURI().toURL()});
Class<?> clazz = classLoader.loadClass(\"MyInterface$Proxy1\");
Constructor<?> constructor = clazz.getConstructor();
Object instance = constructor.newInstance();
MyInterface proxy = (MyInterface) instance;
```<\/p>\n\n\n\n
\u8fd9\u6837\u6211\u4eec\u5c31\u5f97\u5230\u4e86\u4e00\u4e2a\u5728\u8fd0\u884c\u65f6\u52a8\u6001\u521b\u5efa\u7684\u5bf9\u8c61\u3002<\/p>\n\n\n\n
\u7b2c\u56db\u6b65\uff1a\u8ba9\u7c7b\u540d\u548c\u65b9\u6cd5\u4f53\u52a8\u6001\u5316<\/p>\n\n\n\n
\u76ee\u524d\u7c7b\u540d\u548c\u65b9\u6cd5\u4f53\u90fd\u662f\u786c\u7f16\u7801\u7684\u3002\u6211\u4eec\u53ef\u4ee5\u4f18\u5316\uff1a<\/p>\n\n\n\n
- \u7c7b\u540d\u901a\u8fc7\u539f\u5b50\u8ba1\u6570\u5668\u81ea\u589e\uff0c\u907f\u514d\u51b2\u7a81\uff0c\u5982 `MyInterface$Proxy1`\u3001`MyInterface$Proxy2`\u3002
- \u65b9\u6cd5\u4f53\u4e0d\u518d\u56fa\u5b9a\uff0c\u800c\u662f\u7531\u5916\u90e8\u4f20\u5165\u4e00\u4e2a\u201c\u5904\u7406\u5668\u201d\u6765\u51b3\u5b9a\u751f\u6210\u4ec0\u4e48\u4ee3\u7801\u3002<\/p>\n\n\n\n
\u6211\u4eec\u5b9a\u4e49\u4e00\u4e2a\u63a5\u53e3 `MyHandler`\uff1a<\/p>\n\n\n\n
```java
public interface MyHandler {
String getMethodBody(String methodName);
}
```<\/p>\n\n\n\n
\u8fd9\u4e2a\u63a5\u53e3\u7684\u4f5c\u7528\u662f\uff1a\u7ed9\u5b9a\u65b9\u6cd5\u540d\uff0c\u8fd4\u56de\u8be5\u65b9\u6cd5\u4f53\u5185\u8981\u6267\u884c\u7684 Java \u4ee3\u7801\u5b57\u7b26\u4e32\u3002<\/p>\n\n\n\n
\u4f46\u662f\u5982\u4f55\u8fdb\u4e00\u6b65\u7684\u52a8\u6001\u5462\uff1f\u5c31\u662f\u628agetClassName\u6216\u8005 functionBody \u51fd\u6570\u4e5f\u52a8\u6001\uff0c\u6211\u4eec\u65b0\u5efa\u4e00\u4e2aMyHandler\u7684\u6587\u4ef6\uff0c\u83b7\u5f97\u4e00\u4e2a\u65b9\u6cd5\u540d\uff0c\u8fd4\u56de\u4e00\u4e2a\u51fd\u6570\u4f53\uff1a\u52a8\u6001\u4ee3\u7406\u7684\u4e09\u4e2a\u53c2\u6570\uff0c\u52a0\u8f7d\u5668\uff0c\u7c7b\uff0chandler\u90fd\u9f50\u4e86<\/p>\n\n\n\n
\u8fd9\u6837\u6211\u4eec\u4e3a\u539f\u5148\u7684\u4e24\u4e2a\u51fd\u6570\u914d\u7f6e\u4f20\u9012\u65b9\u6cd5\u4f53\uff1a<\/p>\n\n\n\n
public class MyInterfaceFactory {\n\n private static final AtomicInteger count = new AtomicInteger();\n\n private static File createJavaFile(String className, MyHandler handler) throws IOException {\n String func1Body = handler.functionBody(\"func1\");\n String func2Body = handler.functionBody(\"func2\");\n String func3Body = handler.functionBody(\"func3\");\n String context = \"package tech.insight.proxy;\\n\" +\n \"\\n\" +\n \"public class \" + className + \" implements MyInterface {\\n\" +\n \" @Override\\n\" +\n \" public void func1() {\\n\" +\n\n\n\n...............................................<\/code><\/pre>\n\n\n\n\u9009\u62e9\u5220\u6389\u6211\u4eec\u7684pxory\u4e86<\/p>\n\n\n\n
private static MyInterface newInstance(String className) throws Exception {\n Class<?> aClass = MyInterfaceFactory.class.getClassLoader().loadClass(className);\n Constructor<?> constructor = aClass.getConstructor();\n MyInterface proxy = (MyInterface) constructor.newInstance();\n return proxy;\n}\n\npublic static MyInterface createProxyObject(MyHandler myHandler) throws Exception {\n String className = getClassName();\n File javaFile = createJavaFile(className, myHandler);\n Compiler.compile(javaFile);\n return newInstance(\"tech.insight.proxy.\" + className);\n}<\/code><\/pre>\n\n\n\n\u7136\u540e\u5728\u751f\u6210\u7c7b\u65f6\uff0c\u628a `MyHandler` \u4f20\u8fdb\u53bb\uff0c\u7528\u5b83\u6765\u751f\u6210\u6bcf\u79cd\u65b9\u6cd5\u7684\u51fd\u6570\u4f53\uff1a<\/p>\n\n\n\n
```java
for (Method method : MyInterface.class.getDeclaredMethods()) {
String body = handler.getMethodBody(method.getName());
content.append(\" public void \").append(method.getName())
.append(\"() { \").append(body).append(\" }\\n\");
}
```<\/p>\n\n\n\n
\u4f8b\u5982\uff0c\u6211\u4eec\u53ef\u4ee5\u5b9e\u73b0\u4e00\u4e2a\u53ea\u6253\u5370\u65b9\u6cd5\u540d\u7684\u5904\u7406\u5668\uff1a<\/p>\n\n\n\n
```java
public class PrintMethodNameHandler implements MyHandler {
@Override
public String getMethodBody(String methodName) {
return \"System.out.println(\\\"\" + methodName + \"\\\");\";
}
}<\/p>\n\n\n\n
\u4e5f\u53ef\u4ee5\u5b9e\u73b0\u4e00\u4e2a\u5148\u6253\u5370 `\"1\"` \u518d\u6253\u5370\u65b9\u6cd5\u540d\u7684\u5904\u7406\u5668\uff1a<\/p>\n\n\n\n
public class PrintOneThenNameHandler implements MyHandler {
@Override
public String getMethodBody(String methodName) {
StringBuilder sb = new StringBuilder();
sb.append(\"System.out.println(\\\"1\\\");\");
sb.append(\"System.out.println(\\\"\").append(methodName).append(\"\\\");\");
return sb.toString();
}
}<\/p>\n\n\n\n
static class PrintFunctionName1 implements MyHandler {\n\n @Override\n public String functionBody(String methodName) {\n StringBuilder stringBuilder = new StringBuilder();\n stringBuilder.append(\"System.out.println();\")\n .append(\" System.out.println(\\\"\" + methodName + \"\\\");\");\n return stringBuilder.toString();\n }\n}<\/code><\/pre>\n\n\n\n\u6240\u6709\u7684\u5bf9\u8c61\u90fd\u662f\u4ee3\u7406\u62ff\u5230\u7684<\/p>\n\n\n\n
P \u529f\u80fd\uff08\u524d\u7f6e\/\u540e\u7f6e\u589e\u5f3a\uff09<\/p>\n\n\n\n
\u6211\u4eec\u73b0\u5728\u60f3\u5b9e\u73b0\u7c7b\u4f3c Spring AOP \u7684\u529f\u80fd\uff1a\u5728\u65b9\u6cd5\u6267\u884c\u524d\u540e\u81ea\u52a8\u6dfb\u52a0\u65e5\u5fd7\u3002<\/p>\n\n\n\n
\u6211\u4eec\u9700\u8981\u751f\u6210\u8fd9\u6837\u7684\u4ee3\u7801\uff1a<\/p>\n\n\n\n
```java
public void func1() {
System.out.println(\"before\");
myInterface.func1();
System.out.println(\"after\");
}
```<\/p>\n\n\n\n
\u4f46\u8fd9\u91cc\u6709\u4e2a\u95ee\u9898\uff1a\u751f\u6210\u7684\u7c7b\u9700\u8981\u6301\u6709\u4e00\u4e2a\u771f\u5b9e\u7684 `MyInterface` \u5b9e\u4f8b\uff0c\u5e76\u8c03\u7528\u5b83\u7684\u65b9\u6cd5\u3002<\/p>\n\n\n\n
\u56e0\u6b64\uff0c`MyHandler` \u9700\u8981\u80fd\u8bbe\u7f6e\u76ee\u6807\u5bf9\u8c61\u3002\u6211\u4eec\u6269\u5c55\u63a5\u53e3\uff1a\u907f\u514d\u7a7a\u6307\u9488\uff0c\u8fd9\u6837<\/p>\n\n\n\n
```java
public interface MyHandler {
String getMethodBody(String methodName);
default void setProxy(Object proxy) {}
}
```<\/p>\n\n\n\n
public interface MyHandler {\n String functionBody(String methodName);\n\n default void setProxy(MyInterface proxy) {\n }\n}<\/code><\/pre>\n\n\n\n\u9ed8\u8ba4\u65b9\u6cd5\u8868\u793a\u5927\u591a\u6570\u5904\u7406\u5668\u4e0d\u9700\u8981\u8bbe\u7f6e\u4ee3\u7406\u5bf9\u8c61\u3002<\/p>\n\n\n\n
\u53ea\u6709\u50cf `LogHandler` \u8fd9\u6837\u7684\u5904\u7406\u5668\u624d\u9700\u8981\uff1a<\/p>\n\n\n\n
```java
public class LogHandler implements MyHandler {
private final MyInterface target;<\/p>\n\n\n\n
public LogHandler(MyInterface target) {
this.target = target;
}<\/p>\n\n\n\n
@Override
public String getMethodBody(String methodName) {
return \"System.out.println(\\\"before\\\");\" +
\"myInterface.\" + methodName + \"();\" +
\"System.out.println(\\\"after\\\");\";
}<\/p>\n\n\n\n
@Override
public void setProxy(Object proxy) {
try {
Field field = proxy.getClass().getDeclaredField(\"myInterface\");
field.setAccessible(true);
field.set(proxy, target);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
```<\/p>\n\n\n\n
static class LogHandler implements MyHandler {\n\n MyInterface myInterface;\n\n public LogHandler(MyInterface myInterface) {\n this.myInterface = myInterface;\n }\n\n @Override\n public void setProxy(MyInterface proxy) {\n Class<?> extends MyInterface aClass = proxy.getClass();\n Field field = null;\n try {\n field = aClass.getDeclaredField(\"myInterface\");\n field.setAccessible(true);\n field.set(proxy, myInterface);\n } catch (Exception e) {\n throw new RuntimeException(e);\n }\n }<\/code><\/pre>\n\n\n\n\u6211\u4eec\u5728\u751f\u6210\u7684\u7c7b\u4e2d\u6dfb\u52a0\u5b57\u6bb5\uff1a<\/p>\n\n\n\n
```java
content.append(\" private MyInterface myInterface;\\n\");
```<\/p>\n\n\n\n
private static MyInterface newInstance(String className, MyHandler handler) throws Exception {\n Class<?> aClass = MyInterfaceFactory.class.getClassLoader().loadClass(className);\n Constructor<?> constructor = aClass.getConstructor();\n MyInterface proxy = (MyInterface) constructor.newInstance();\n handler.setProxy(proxy);\n return proxy;\n}\n\npublic static MyInterface createProxyObject(MyHandler myHandler) throws Exception {\n String className = getClassName();\n File javaFile = createJavaFile(className, myHandler);\n Compiler.compile(javaFile);\n return newInstance(\"tech.insight.proxy.\" + className, myHandler);\n}<\/code><\/pre>\n\n\n\n\u5e76\u5728 `newInstance()` \u65f6\u8c03\u7528 `handler.setProxy(proxy)` \u5b8c\u6210\u8d4b\u503c\u3002<\/p>\n\n\n\n
proxyObject= MyInterfaceFactory.createProxyObject(new LogHandler(proxyObject));<\/strong><\/p>\n\n\n\n\u6700\u7ec8\uff0c\u6211\u4eec\u6210\u529f\u5b9e\u73b0\u4e86\uff1a<\/p>\n\n\n\n
- \u52a8\u6001\u751f\u6210\u5b9e\u73b0\u4e86 `MyInterface` \u7684\u7c7b\uff1b
- \u65b9\u6cd5\u4f53\u5185\u5bb9\u7531 `MyHandler` \u63a7\u5236\uff1b
- \u652f\u6301\u5728\u65b9\u6cd5\u524d\u540e\u63d2\u5165\u903b\u8f91\uff0c\u5b9e\u73b0 AOP \u589e\u5f3a\u3002<\/p>\n\n\n\n
\u8fd9\u5c31\u662f\u6211\u4eec\u5199\u7684\u52a8\u6001\u4ee3\u7406 \u90a3\u4e48\u518d\u56de\u987e\u4e00\u4e0b \u6211\u4eec\u662f\u5982\u4f55\u5199\u6211\u4eec\u7684\u52a8\u6001\u4ee3\u7406\u7684\u5462 \u9996\u5148\u6211\u4eec\u751f\u6210\u4e86\u4e00\u4e2a\u6587\u5b57\u7248\u7684java\u7c7b \u7136\u540e\u6211\u4eec\u5728\u8fd0\u884c\u65f6\u628a\u5b83\u7f16\u8bd1 \u518d\u7528\u901a\u8fc7class loader\u53bb\u628a\u8fd9\u4e2a\u7f16\u8bd1\u51fa\u6765\u7684\u5b57\u8282\u7801 \u6587\u4ef6\u52a0\u8f7d\u5230\u865a\u62df\u673a\u4e2d \u7136\u540e\u518d\u901a\u8fc7\u53cd\u5c04\u53bb\u521b\u5efa\u8fd9\u4e2a\u7c7b \u7136\u540e\u518d\u8c03\u7528\u8fd9\u4e2a\u7c7b\u5bf9\u5e94\u7684\u65b9\u6cd5 \u8fd9\u5c31\u662f\u6211\u4eec\u5199\u7684\u52a8\u6001\u4ee3\u7406<\/p>\n\n\n\n
\u867d\u7136\u529f\u80fd\u5b8c\u6574\uff0c\u4f46\u5b83\u6709\u660e\u663e\u7f3a\u9677\uff1a<\/p>\n\n\n\n
1. \u53ea\u80fd\u4ee3\u7406 `MyInterface`\uff0c\u65e0\u6cd5\u6cdb\u5316\uff1b
2. \u4f9d\u8d56\u78c1\u76d8 IO \u548c\u7f16\u8bd1\u8fc7\u7a0b\uff0c\u6027\u80fd\u5dee\uff1b
3. \u751f\u6210\u7684\u662f Java \u6e90\u7801\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u64cd\u4f5c\u5b57\u8282\u7801\u3002<\/p>\n\n\n\n
\u800c JDK \u81ea\u5e26\u7684\u52a8\u6001\u4ee3\u7406\uff08`java.lang.reflect.Proxy`\uff09\u548c CGLIB \u5219\u66f4\u9ad8\u6548\uff0c\u5b83\u4eec\u53ef\u4ee5\u76f4\u63a5\u5728\u5185\u5b58\u4e2d\u751f\u6210\u5b57\u8282\u7801\uff0c\u65e0\u9700\u5199\u6587\u4ef6\u548c\u7f16\u8bd1\u3002<\/p>\n\n\n\n
Spring \u7684\u4e8b\u52a1\u7ba1\u7406\u5e95\u5c42\u5c31\u662f\u57fa\u4e8e\u52a8\u6001\u4ee3\u7406\u3002\u5f53\u4f60\u5728\u4e00\u4e2a\u52a0\u4e86 `@Transactional` \u7684\u65b9\u6cd5\u4e0a\u6267\u884c\u6570\u636e\u5e93\u64cd\u4f5c\u65f6\uff0cSpring \u4f1a\u751f\u6210\u4e00\u4e2a\u4ee3\u7406\u5bf9\u8c61\uff0c\u5728\u65b9\u6cd5\u6267\u884c\u524d\u540e\u81ea\u52a8\u5f00\u542f\u4e8b\u52a1\u3001\u63d0\u4ea4\u6216\u56de\u6eda\uff1a<\/p>\n\n\n\n
```java
try {
\u5f00\u542f\u4e8b\u52a1();
target.insert(); \/\/ \u771f\u5b9e\u4e1a\u52a1\u903b\u8f91
\u63d0\u4ea4\u4e8b\u52a1();
} catch (RuntimeException e) {
\u56de\u6eda\u4e8b\u52a1();
throw e;
}
```<\/p>\n\n\n\n
\u7406\u89e3\u8fd9\u4e00\u70b9\u540e\uff0c\u5c31\u80fd\u660e\u767d\u4e3a\u4ec0\u4e48\u6709\u4e9b\u60c5\u51b5\u4e0b\u4e8b\u52a1\u4f1a\u5931\u6548\uff1a<\/p>\n\n\n\n
- \u5982\u679c\u4f60\u6355\u83b7\u4e86\u5f02\u5e38\u5e76\u201c\u541e\u6389\u201d\uff0c\u4ee3\u7406\u5c42\u65e0\u6cd5\u611f\u77e5\u5f02\u5e38\uff0c\u5c31\u4e0d\u4f1a\u56de\u6eda\uff1b
- \u5982\u679c\u629b\u51fa\u7684\u662f checked exception\uff08\u975e `RuntimeException`\uff09\uff0c\u9ed8\u8ba4\u4e0d\u4f1a\u89e6\u53d1\u56de\u6eda\uff0c\u9664\u975e\u663e\u5f0f\u914d\u7f6e\uff1b
- \u5982\u679c\u81ea\u8c03\u7528\uff08this.method()\uff09\uff0c\u7ed5\u8fc7\u4e86\u4ee3\u7406\u5bf9\u8c61\uff0cAOP \u4e0d\u751f\u6548\u3002<\/p>\n\n\n\n
\u601d\u8003\u9898\uff1a
\u4f60\u80fd\u57fa\u4e8e\u4ee5\u4e0a\u601d\u8def\uff0c\u81ea\u5df1\u5b9e\u73b0\u4e00\u4e2a\u652f\u6301 `before`\u3001`after`\u3001`around` \u7684\u901a\u7528\u589e\u5f3a\u5904\u7406\u5668\u5417\uff1f \u200b<\/p>\n","protected":false},"excerpt":{"rendered":"
\u8fd9\u662f\u4e00\u4e2a\u65b0\u7684\u5de5\u7a0b\u3002\u6211\u4eec\u6709\u4e00\u4e2a\u63a5\u53e3\u53eb `MyInterface`\uff0c\u91cc\u9762\u5b9a\u4e49\u4e86\u4e09\u4e2a\u65b9\u6cd5\uff1a`func1()`\u3001`func2()` \u548c ` …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"emotion":"","emotion_color":"","title_style":"","license":"","footnotes":""},"categories":[3,2],"tags":[33,34],"class_list":["post-1244","post","type-post","status-publish","format-standard","hentry","category-3","category-2","tag-jdk","tag-34"],"_links":{"self":[{"href":"https:\/\/eve2333.top\/index.php?rest_route=\/wp\/v2\/posts\/1244","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/eve2333.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/eve2333.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/eve2333.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/eve2333.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1244"}],"version-history":[{"count":1,"href":"https:\/\/eve2333.top\/index.php?rest_route=\/wp\/v2\/posts\/1244\/revisions"}],"predecessor-version":[{"id":1245,"href":"https:\/\/eve2333.top\/index.php?rest_route=\/wp\/v2\/posts\/1244\/revisions\/1245"}],"wp:attachment":[{"href":"https:\/\/eve2333.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1244"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/eve2333.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1244"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/eve2333.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1244"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}