/*
* Copyright 2006-2007 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.batch.repeat.policy;
import org.springframework.batch.repeat.RepeatStatus;
import org.springframework.batch.repeat.RepeatContext;
import org.springframework.batch.repeat.context.RepeatContextSupport;
import org.springframework.batch.repeat.support.RepeatTemplate;
import org.springframework.util.ClassUtils;
/**
* Policy for terminating a batch after a fixed number of operations. Internal
* state is maintained and a counter incremented, so successful use of this
* policy requires that isComplete() is only called once per batch item. Using
* the standard {@link RepeatTemplate} should ensure this contract is kept, but it needs
* to be carefully monitored.
*
* @author Dave Syer
*
*/
public class SimpleCompletionPolicy extends DefaultResultCompletionPolicy {
public static final int DEFAULT_CHUNK_SIZE = 5;
int chunkSize = 0;
public SimpleCompletionPolicy() {
this(DEFAULT_CHUNK_SIZE);
}
public SimpleCompletionPolicy(int chunkSize) {
super();
this.chunkSize = chunkSize;
}
public void setChunkSize(int chunkSize) {
this.chunkSize = chunkSize;
}
/**
* Reset the counter.
*
* @see org.springframework.batch.repeat.CompletionPolicy#start(RepeatContext)
*/
@Override
public RepeatContext start(RepeatContext context) {
return new SimpleTerminationContext(context);
}
/**
* Terminate if the chunk size has been reached, or the result is null.
*
* @see org.springframework.batch.repeat.CompletionPolicy#isComplete(RepeatContext,
* RepeatStatus)
* @throws RuntimeException (normally terminating the batch) if the result is
* itself an exception.
*/
@Override
public boolean isComplete(RepeatContext context, RepeatStatus result) {
return super.isComplete(context, result) || ((SimpleTerminationContext) context).isComplete();
}
/**
* Terminate if the chunk size has been reached.
*
* @see org.springframework.batch.repeat.CompletionPolicy#isComplete(RepeatContext)
*/
@Override
public boolean isComplete(RepeatContext context) {
return ((SimpleTerminationContext) context).isComplete();
}
/**
* Increment the counter in the context.
*
* @see org.springframework.batch.repeat.CompletionPolicy#update(RepeatContext)
*/
@Override
public void update(RepeatContext context) {
((SimpleTerminationContext) context).update();
}
protected class SimpleTerminationContext extends RepeatContextSupport {
public SimpleTerminationContext(RepeatContext context) {
super(context);
}
public void update() {
increment();
}
public boolean isComplete() {
return getStartedCount() >= chunkSize;
}
}
/* (non-Javadoc)
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
return ClassUtils.getShortName(SimpleCompletionPolicy.class)+": chunkSize="+chunkSize;
}
}