CGlib动态代理实现

liuxun · liuxun · commit e8bb5596b412 · 2017-12-04T15:58:10.000+08:00
diff --git a/pom.xml b/pom.xml
@@ -14,5 +14,11 @@
             <groupId>com.alibaba</groupId>
             <version>1.2.9</version>
         </dependency>
+        <!-- https://mvnrepository.com/artifact/cglib/cglib -->
+        <dependency>
+            <groupId>cglib</groupId>
+            <artifactId>cglib</artifactId>
+            <version>2.2.2</version>
+        </dependency>
     </dependencies>
 </project>
diff --git a/src/main/java/com/algorithm/study/demo/jvm/StackSOF.java b/src/main/java/com/algorithm/study/demo/jvm/StackSOF.java
@@ -12,7 +12,7 @@ public void stackLeak(){
         stackLength++;
         stackLeak();
     }
-    public static void main(String[] args) {
+    public static void main(String[] args) throws Exception {
         StackSOF sof=new StackSOF();
         try {
             sof.stackLeak();
diff --git a/src/main/java/com/algorithm/study/demo/reflect/CGlibProxyFactory.java b/src/main/java/com/algorithm/study/demo/reflect/CGlibProxyFactory.java
@@ -0,0 +1,46 @@
+package com.algorithm.study.demo.reflect;
+
+import net.sf.cglib.proxy.Enhancer;
+import net.sf.cglib.proxy.MethodInterceptor;
+import net.sf.cglib.proxy.MethodProxy;
+
+import java.lang.reflect.Method;
+
+/**
+ * @author liuxun
+ * @version V1.0
+ * @Description: Cglib动态代理；cglib是针对类来实现代理的，他的原理是对指定的目标类生成一个子类，并覆盖其中方法实现增强，但因为采用的是继承，所以不能对final修饰的类进行代理。
+ * @date 2017/12/1
+ */
+public class CGlibProxyFactory implements MethodInterceptor{
+    private Object target;
+    /**
+     * 回调方法
+     * @param proxy
+     * @param method
+     * @param args
+     * @param methodProxy
+     * @return
+     * @throws Throwable
+     */
+    @Override
+    public Object intercept(Object proxy, Method method, Object[] args, MethodProxy methodProxy) throws Throwable {
+        PerformanceMonitor.begin();
+        method.invoke(target,args);
+        PerformanceMonitor.end();
+        return null;
+    }
+
+    public Object getInstance(Object target){
+        this.target=target;
+        //通过enhancer生成代理对象
+        Enhancer enhancer=new Enhancer();
+        //设置目标类的子类，该子类会覆盖所有父类中的非final方法
+        enhancer.setSuperclass(this.target.getClass());
+        //设置回调方法
+        enhancer.setCallback(this);
+        return enhancer.create();
+    }
+
+
+}
diff --git a/src/main/java/com/algorithm/study/demo/reflect/CGlibServiceImpl.java b/src/main/java/com/algorithm/study/demo/reflect/CGlibServiceImpl.java
@@ -0,0 +1,13 @@
+package com.algorithm.study.demo.reflect;
+
+/**
+ * @author liuxun
+ * @version V1.0
+ * @Description: 没有实现接口的类
+ * @date 2017/12/4
+ */
+public class CGlibServiceImpl {
+    public void excute(){
+        System.out.println("开始执行没有实现接口的类的方法...");
+    }
+}
diff --git a/src/main/java/com/algorithm/study/demo/reflect/Test.java b/src/main/java/com/algorithm/study/demo/reflect/Test.java
@@ -14,10 +14,15 @@
  */
 public class Test {
     public static void main(String[] args) {
+        //基于JDK的动态代理
         Service service=new ServiceImpl();
         ServiceHandler serviceHandler=new ServiceHandler(service);
         Service proxy = (Service)serviceHandler.createProxyIntance();
-//        Service proxy = (Service) Proxy.newProxyInstance(service.getClass().getClassLoader(),service.getClass().getInterfaces(),serviceHandler);
         proxy.service("hello reflect");
+
+        //基于CGlib动态代理实现
+        CGlibProxyFactory cglib=new CGlibProxyFactory();
+        CGlibServiceImpl object = (CGlibServiceImpl)cglib.getInstance(new CGlibServiceImpl());
+        object.excute();
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -12,7 +12,7 @@ public void stackLeak(){`
`12`	`12`	`stackLength++;`
`13`	`13`	`stackLeak();`
`14`	`14`	`}`
`15`		`- public static void main(String[] args) {`
	`15`	`+ public static void main(String[] args) throws Exception {`
`16`	`16`	`StackSOF sof=new StackSOF();`
`17`	`17`	`try {`
`18`	`18`	`sof.stackLeak();`