package org.aopalliance.intercept;

Intercepts calls on an interface on its way to the target. These
are nested "on top" of the target.
The user should implement the invoke(MethodInvocation) method to modify the original behavior. E.g. the following class implements a tracing interceptor (traces all the calls on the intercepted method(s)): 
class TracingInterceptor implements MethodInterceptor {
  Object invoke(MethodInvocation i) throws Throwable {
    System.out.println("method "+i.getMethod()+" is called on "+
                       i.getThis()+" with args "+i.getArguments());
    Object ret=i.proceed();
    System.out.println("method "+i.getMethod()+" returns "+ret);
    return ret;
  }
}
 /**
 * Intercepts calls on an interface on its way to the target. These
 * are nested "on top" of the target.
 *
 * <p>The user should implement the {@link #invoke(MethodInvocation)}
 * method to modify the original behavior. E.g. the following class
 * implements a tracing interceptor (traces all the calls on the
 * intercepted method(s)):
 *
 * <pre class=code>
 * class TracingInterceptor implements MethodInterceptor {
 *   Object invoke(MethodInvocation i) throws Throwable {
 *     System.out.println("method "+i.getMethod()+" is called on "+
 *                        i.getThis()+" with args "+i.getArguments());
 *     Object ret=i.proceed();
 *     System.out.println("method "+i.getMethod()+" returns "+ret);
 *     return ret;
 *   }
 * }
 * </pre> */

public interface MethodInterceptor extends Interceptor {
	
    
Implement this method to perform extra treatments before and after the invocation. Polite implementations would certainly like to invoke Joinpoint.proceed(). 
Params:
invocation – the method invocation joinpoint
Throws:
Throwable – if the interceptors or the
target-object throws an exception.
Returns:
the result of the call to Joinpoint.proceed(), might be intercepted by the interceptor./**
     * Implement this method to perform extra treatments before and
     * after the invocation. Polite implementations would certainly
     * like to invoke {@link Joinpoint#proceed()}.
     *
     * @param invocation the method invocation joinpoint
     * @return the result of the call to {@link
     * Joinpoint#proceed()}, might be intercepted by the
     * interceptor.
     *
     * @throws Throwable if the interceptors or the
     * target-object throws an exception.  */
    Object invoke(MethodInvocation invocation) throws Throwable;
}