本篇文章不讲cglib如何应用,只从eclipse调试的角度看看从最外层的动态代理类调用到最内层的被代理类,经过了哪些中间步骤。
废话不多说,直接上代码
被代理类:
public class MySubject { public void doSomeThing() { System.err.println("Do some thing!"); } }
拦截器:
public class CgLibMethodInterceptor implements MethodInterceptor { @Override public Object intercept(Object target, Method method, Object[] args, MethodProxy proxy) throws Throwable { System.err.println("before "); Object result = proxy.invokeSuper(target, args); System.err.println("after " + result); return result; } }
测试cglib动态代理:
public class CglibProxyWriter { public static void main(String[] args) { System.setProperty(DebuggingClassWriter.DEBUG_LOCATION_PROPERTY, "D:\cglib-class\"); MySubject subject= (MySubject) Enhancer.create(MySubject.class,new CgLibMethodInterceptor()); subject.doSomeThing(); } }
从调用栈可以清晰的看到最外层到最内层的调用逻辑。
MySubject$$EnhancerByCGLIB$$24226c3c(MySubject).doSomeThing() line: 6
MySubject$$EnhancerByCGLIB$$24226c3c.CGLIB$doSomeThing$0() line: not available
MySubject$$EnhancerByCGLIB$$24226c3c$$FastClassByCGLIB$$a7941ac2.invoke(int, Object, Object[]) line: not available
MethodProxy.invokeSuper(Object, Object[]) line: 244
CgLibMethodInterceptor.intercept(Object, Method, Object[], MethodProxy) line: 14
MySubject$$EnhancerByCGLIB$$24226c3c.doSomeThing() line: not available
CglibProxyWriter.main(String[]) line: 16
MySubject$$EnhancerByCGLIB$$24226c3c(MySubject).doSomeThing() line: 6
MySubject$$EnhancerByCGLIB$$24226c3c.CGLIB$doSomeThing$0() line: not available
MySubject$$EnhancerByCGLIB$$24226c3c$$FastClassByCGLIB$$a7941ac2.invoke(int, Object, Object[]) line: not available
MethodProxy.invokeSuper(Object, Object[]) line: 244
CgLibMethodInterceptor.intercept(Object, Method, Object[], MethodProxy) line: 14
MySubject$$EnhancerByCGLIB$$24226c3c.doSomeThing() line: not available
CglibProxyWriter.main(String[]) line: 16
eclipse调试的时候不能加上断点,cglib动态生成的代理类需要反编译工具查看,截图已经提供了反编译后的代码。