http://aopalliance.sourceforge.net: AOP Alliance
  • Public Domain 

package org.aopalliance.intercept;

import org.aopalliance.aop.Advice;


This interface represents a generic interceptor.

A generic interceptor can intercept runtime events that occur
within a base program. Those events are materialized by (reified
in) joinpoints. Runtime joinpoints can be invocations, field
access, exceptions... 

This interface is not used directly. Use the the sub-interfaces
to intercept specific events. For instance, the following class
implements some specific interceptors in order to implement a
debugger:

class DebuggingInterceptor implements MethodInterceptor, 
    ConstructorInterceptor, FieldInterceptor {
  Object invoke(MethodInvocation i) throws Throwable {
    debug(i.getMethod(), i.getThis(), i.getArgs());
    return i.proceed();
  }
  Object construct(ConstructorInvocation i) throws Throwable {
    debug(i.getConstructor(), i.getThis(), i.getArgs());
    return i.proceed();
  }
  Object get(FieldAccess fa) throws Throwable {
    debug(fa.getField(), fa.getThis(), null);
    return fa.proceed();
  }
  Object set(FieldAccess fa) throws Throwable {
    debug(fa.getField(), fa.getThis(), fa.getValueToSet());
    return fa.proceed();
  }
  void debug(AccessibleObject ao, Object this, Object value) {
    ...
  }
}



See Also:
  • Joinpoint
/**
 * This interface represents a generic interceptor.
 *
 * <p>A generic interceptor can intercept runtime events that occur
 * within a base program. Those events are materialized by (reified
 * in) joinpoints. Runtime joinpoints can be invocations, field
 * access, exceptions... 
 *
 * <p>This interface is not used directly. Use the the sub-interfaces
 * to intercept specific events. For instance, the following class
 * implements some specific interceptors in order to implement a
 * debugger:
 *
 * <pre class=code>
 * class DebuggingInterceptor implements MethodInterceptor, 
 *     ConstructorInterceptor, FieldInterceptor {
 *
 *   Object invoke(MethodInvocation i) throws Throwable {
 *     debug(i.getMethod(), i.getThis(), i.getArgs());
 *     return i.proceed();
 *   }
 *
 *   Object construct(ConstructorInvocation i) throws Throwable {
 *     debug(i.getConstructor(), i.getThis(), i.getArgs());
 *     return i.proceed();
 *   }
 * 
 *   Object get(FieldAccess fa) throws Throwable {
 *     debug(fa.getField(), fa.getThis(), null);
 *     return fa.proceed();
 *   }
 *
 *   Object set(FieldAccess fa) throws Throwable {
 *     debug(fa.getField(), fa.getThis(), fa.getValueToSet());
 *     return fa.proceed();
 *   }
 *
 *   void debug(AccessibleObject ao, Object this, Object value) {
 *     ...
 *   }
 * }
 * </pre>
 *
 * @see Joinpoint */

public interface Interceptor extends Advice {
}