java.lang.reflect.Proxy.getInvocationHandler() Method Example

Description

The java.lang.reflect.Proxy.getInvocationHandler(Object proxy) method returns the invocation handler for the specified proxy instance.

Declaration

Following is the declaration for java.lang.reflect.Proxy.getInvocationHandler(Object proxy) method.

public static InvocationHandler getInvocationHandler(Object proxy)
   throws IllegalArgumentException

Parameters

proxy − the proxy instance to return the invocation handler for.

Returns

the invocation handler for the proxy instance.

Exceptions

IllegalArgumentException − if the argument is not a proxy instance.

Example

The following example shows the usage of java.lang.reflect.Proxy.getInvocationHandler(Object proxy) method.

package com.tutorialspoint;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

public class ProxyDemo {
   public static void main(String[] args) throws IllegalArgumentException {
      InvocationHandler handler = new SampleInvocationHandler() ;
      SampleInterface proxy = (SampleInterface) Proxy.newProxyInstance(
         SampleInterface.class.getClassLoader(),
         new Class[] { SampleInterface.class },
         handler);
      Class invocationHandler = Proxy.getInvocationHandler(proxy).getClass();

      System.out.println(invocationHandler.getName());
   }
}

class SampleInvocationHandler implements InvocationHandler {

   @Override
   public Object invoke(Object proxy, Method method, Object[] args)
      throws Throwable {
      System.out.println("Welcome to TutorialsPoint");   
      return null;
   }
}

interface SampleInterface {
   void showMessage();
}

class SampleClass implements SampleInterface {
   public void showMessage(){
      System.out.println("Hello World");   
   }
}

Let us compile and run the above program, this will produce the following result −

com.tutorialspoint.SampleInvocationHandler