I'm a little bit confused by this scenario:
I have a class that implements InvocationHandler interface mentioned in title, class that looks like :
class SimpleProxy implements InvocationHandler{
private Object proxied;
public SimpleProxy(Object proxied) {
this.proxied = proxied;
}
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
System.out.println(proxy);
return method.invoke(proxied, args);
}
}
and lets say in my "main" method I have:
public static void main(String[] args) {
consumer(new RealObject());
MyInterface proxy = (MyInterface)Proxy.newProxyInstance(MainClass.class.getClassLoader(), new Class[]{MyInterface.class}, new SimpleProxy(new MyInterfaceImpl()));
proxy.methodFromMyInterface();
}
Now the problem is that the "invoke" throws an error like:
...
at rtti.SimpleProxy.invoke(MainClass.java:81)
at rtti.$Proxy0.toString(Unknown Source)
at java.lang.String.valueOf(String.java:2826)
at java.io.PrintStream.println(PrintStream.java:771)
at rtti.SimpleProxy.invoke(MainClass.java:81)
at rtti.$Proxy0.toString(Unknown Source)
at java.lang.String.valueOf(String.java:2826)
at java.io.PrintStream.println(PrintStream.java:771)
...
because of this line :
System.out.println(proxy);
If I comment this line everithing works fine.
Can anybody explain me what's the problem?
N.B. In the Java docs it says about invoke method from InvocationHandler:
Processes a method invocation on a proxy instance and returns the result. This method will be invoked on an invocation handler when a method is invoked on a proxy instance that it is associated with.
Parameters: proxy - the proxy instance that the method was invoked on
... so I can't understand why it is going wrong ...
System.out.println(proxy); will implicitly call toString() on the proxy, i.e. call a proxied method.