org.apache.james.util.retry

Class ExceptionRetryHandler

java.lang.Object

org.apache.james.util.retry.ExceptionRetryHandler

All Implemented Interfaces:

RetryHandler

Direct Known Subclasses:

NamingExceptionRetryHandler

public abstract class ExceptionRetryHandler
extends Object
implements RetryHandler

Abstract class ExceptionRetryHandler retries the behaviour defined in abstract method operation() implemented in a concrete subclass when nominated subclasses of Exception are thrown. The intervals between retries are defined by a RetrySchedule.

Concrete subclasses are proxies that forward work via the operation() to a delegate instance for which retry behaviour is required. Both the proxy and the delegate implement the same interfaces.

The method stubs required to perform the proxy call via operation() may be generated by many means, including explicit code, a DynamicProxy and compile time aspect injection.

See Also:

RetryingContext

Constructor Summary

Constructors

Constructor and Description
ExceptionRetryHandler(Class<?>[] exceptionClasses, ExceptionRetryingProxy proxy, RetrySchedule schedule, int maxRetries) Creates a new instance of ExceptionRetryHandler.

Method Summary

Methods

Modifier and Type	Method and Description
long	getRetryInterval(int retryCount)
abstract Object	operation() Encapsulates desired behaviour
Object	perform()
void	postFailure(Exception ex, int retryCount) A hook invoked each time an operation fails if a retry is scheduled

Methods inherited from class java.lang.Object

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

Constructor Detail

ExceptionRetryHandler

public ExceptionRetryHandler(Class<?>[] exceptionClasses,
                     ExceptionRetryingProxy proxy,
                     RetrySchedule schedule,
                     int maxRetries)

Creates a new instance of ExceptionRetryHandler.

Parameters:

exceptionClasses -

proxy -

maxRetries -

Method Detail

perform

public Object perform()
               throws Exception

Specified by:

perform in interface RetryHandler

Returns:

the result of invoking an operation

Throws:

Exception

See Also:

org.apache.james.user.ldap.api.RetryHandler#perform()

postFailure

public void postFailure(Exception ex,
               int retryCount)

Description copied from interface: RetryHandler

A hook invoked each time an operation fails if a retry is scheduled

Specified by:

postFailure in interface RetryHandler

Parameters:

ex - The Exception thrown when the operation was invoked

retryCount - The number of times

See Also:

org.apache.james.user.ldap.api.RetryHandler#postFailure(javax.naming.NamingException, int)

operation

public abstract Object operation()
                          throws Exception

Description copied from interface: RetryHandler

Encapsulates desired behaviour

Specified by:

operation in interface RetryHandler

Returns:

The result of performing the behaviour

Throws:

Exception

See Also:

org.apache.james.user.ldap.api.RetryHandler#operation()

getRetryInterval

public long getRetryInterval(int retryCount)

Returns:

the retryInterval