org.jaffa.persistence.engines.jdbcengine.interceptor
Class AbstractInterceptor

java.lang.Object
  org.jaffa.persistence.engines.jdbcengine.interceptor.AbstractInterceptor

Direct Known Subclasses:

AddInterceptor, DeleteInterceptor, LockInterceptor, QueryInterceptor, UpdateInterceptor

public abstract class AbstractInterceptor

extends Object

This is the abstract class for an Interceptor. All new interceptors must inherit from this base class. A set of interceptors exists the Engine.

Constructor Summary

AbstractInterceptor()

Method Summary

AbstractInterceptor	getNextInterceptor() Returns the next Interceptor in the chain.
abstract Object	invoke(PersistentTransaction pt) Performs the actual logic associated with the interceptor.
void	setNextInterceptor(AbstractInterceptor next) Sets the next Interceptor in the chain.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AbstractInterceptor

public AbstractInterceptor()

Method Detail

setNextInterceptor

public void setNextInterceptor(AbstractInterceptor next)

Sets the next Interceptor in the chain.

Parameters:

next - the next Interceptor in the chain.

getNextInterceptor

public AbstractInterceptor getNextInterceptor()

Returns the next Interceptor in the chain. A null will be returned in case this is the end of the chain.

Returns:

the next Interceptor in the chain.

invoke

public abstract Object invoke(PersistentTransaction pt)
                       throws UOWException

Performs the actual logic associated with the interceptor. Should contain atomic logic, i.e., does not assumes input or output of other interceptors in the chain.

Parameters:

pt - The PersistentTransaction object, on which the Interceptor is to be executed.

Returns:

the output from the next Interceptor in the chain.

Throws:

UOWException - if any error occurs.