org.springframework.batch.repeat.exception

Class RethrowOnThresholdExceptionHandler

java.lang.Object

org.springframework.batch.repeat.exception.RethrowOnThresholdExceptionHandler

All Implemented Interfaces:

ExceptionHandler

public class RethrowOnThresholdExceptionHandler
extends java.lang.Object
implements ExceptionHandler

Implementation of ExceptionHandler that rethrows when exceptions of a given type reach a threshold. Requires an Classifier that maps exception types to unique keys, and also a map from those keys to threshold values (Integer type).

Author:

Dave Syer

Field Summary

Fields

Modifier and Type	Field and Description
protected org.apache.commons.logging.Log	logger
protected static org.springframework.batch.repeat.exception.RethrowOnThresholdExceptionHandler.IntegerHolder	ZERO

Constructor Summary

Constructors

Constructor and Description
RethrowOnThresholdExceptionHandler() Set up the exception handler.

Method Summary

Modifier and Type	Method and Description
void	handleException(RepeatContext context, java.lang.Throwable throwable) Classify the throwables and decide whether to re-throw based on the result.
void	setThresholds(java.util.Map<java.lang.Class<? extends java.lang.Throwable>,java.lang.Integer> thresholds) A map from exception classes to a threshold value of type Integer.
void	setUseParent(boolean useParent) Flag to indicate the the exception counters should be shared between sibling contexts in a nested batch.

Methods inherited from class java.lang.Object

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

Field Detail

ZERO

protected static final org.springframework.batch.repeat.exception.RethrowOnThresholdExceptionHandler.IntegerHolder ZERO

logger

protected final org.apache.commons.logging.Log logger

Constructor Detail

RethrowOnThresholdExceptionHandler

public RethrowOnThresholdExceptionHandler()

Set up the exception handler. Creates a default exception handler and threshold that maps all exceptions to a threshold of 0 - all exceptions are rethrown by default.

Method Detail

setUseParent

public void setUseParent(boolean useParent)

Flag to indicate the the exception counters should be shared between sibling contexts in a nested batch. Default is false.

Parameters:

useParent - true if the parent context should be used to store the counters.

setThresholds

public void setThresholds(java.util.Map<java.lang.Class<? extends java.lang.Throwable>,java.lang.Integer> thresholds)

A map from exception classes to a threshold value of type Integer.

Parameters:

thresholds - the threshold value map.

handleException

public void handleException(RepeatContext context,
                            java.lang.Throwable throwable)
                     throws java.lang.Throwable

Classify the throwables and decide whether to re-throw based on the result. The context is used to accumulate the number of exceptions of the same type according to the classifier.

Specified by:

handleException in interface ExceptionHandler

Parameters:

context - the current RepeatContext. Can be used to store state (via attributes), for example to count the number of occurrences of a particular exception type and implement a threshold policy.

throwable - an exception.

Throws:

java.lang.Throwable - is thrown if number of exceptions exceeds threshold.

See Also:

ExceptionHandler.handleException(RepeatContext, Throwable)