ch.elca.el4j.services.exceptionhandler.handler
Class AbstractSwappableTargetExceptionHandler

java.lang.Object
  ch.elca.el4j.services.exceptionhandler.handler.AbstractExceptionHandler
      ch.elca.el4j.services.exceptionhandler.handler.AbstractRetryExceptionHandler
          ch.elca.el4j.services.exceptionhandler.handler.AbstractSwappableTargetExceptionHandler

All Implemented Interfaces:

ExceptionHandler

Direct Known Subclasses:

RoundRobinSwappableTargetExceptionHandler

public abstract class AbstractSwappableTargetExceptionHandler
extends AbstractRetryExceptionHandler

This class simplifies the implementation of exception handlers that use another implementation with the same interface to fulfil the callers invocation.

Author:

Andreas Bur (ABU)

See Also:

AbstractReconfigureExceptionHandler

File-location:

AbstractSwappableTargetExceptionHandler

Last check-in date:

2009-08-04 13:59:45 +0200 (Di, 04. Aug 2009) by swismer for revision 3873

Constructor Summary

AbstractSwappableTargetExceptionHandler()

Method Summary

protected abstract Object	getNewTarget(Object current, Throwable t, org.aopalliance.intercept.MethodInvocation invocation, org.slf4j.Logger logger) Determines a new target to be used by the proxy.
protected Object	retry(Throwable t, AbstractExceptionHandlerInterceptor exceptionInvoker, org.aopalliance.intercept.MethodInvocation invocation, org.slf4j.Logger logger) Creates a new retry exception.
void	setSwapper(HotSwappableTargetSource swapper) Sets the TargetSource that is used in the proxy, where the target has to be swapped.

Methods inherited from class ch.elca.el4j.services.exceptionhandler.handler.AbstractRetryExceptionHandler

getRetries, handleException, setRetries

Methods inherited from class ch.elca.el4j.services.exceptionhandler.handler.AbstractExceptionHandler

getInvocationDescription, handleException, setUseDynamicLogger

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractSwappableTargetExceptionHandler

public AbstractSwappableTargetExceptionHandler()

Method Detail

setSwapper

public void setSwapper(HotSwappableTargetSource swapper)

Sets the TargetSource that is used in the proxy, where the target has to be swapped.

Parameters:

swapper - The TargetSource to set.

retry

protected Object retry(Throwable t,
                       AbstractExceptionHandlerInterceptor exceptionInvoker,
                       org.aopalliance.intercept.MethodInvocation invocation,
                       org.slf4j.Logger logger)
                throws InappropriateHandlerException,
                       RetryException

Creates a new retry exception. Subclasses may also do some other tasks (e.g. waiting). This method is called only if the number of retires is not already exceeded.

Specified by:

retry in class AbstractRetryExceptionHandler

Parameters:

t - The exception thrown in the method invocation.

exceptionInvoker - The exception invoker that called this exception handler.

invocation - The original method invocation.

logger - The logger to be used by subclasses.

Returns:

Returns an object that is treated as the original invocation's return value.

Throws:

InappropriateHandlerException

RetryException

getNewTarget

protected abstract Object getNewTarget(Object current,
                                       Throwable t,
                                       org.aopalliance.intercept.MethodInvocation invocation,
                                       org.slf4j.Logger logger)
                                throws RetryException,
                                       Throwable

Determines a new target to be used by the proxy.

Parameters:

current - The current target which the proxy is working on.

t - The exception that caused this strategy. Subclasses may distinguish between different exception types.

invocation - The original invocation that failed.

logger - The logger.

Returns:

Returns an alternative bean that implements the same interface as the original one.

Throws:

RetryException - Signals that the complete invocation has to be rerun.

Throwable - Whenever something goes wrong.