public interface Interceptor extends Advice
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 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) { ... } }
Joinpoint