org.springframework.batch.integration.chunk.ChunkProcessorChunkHandler.java Source code

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Here is the source code for org.springframework.batch.integration.chunk.ChunkProcessorChunkHandler.java

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/*
 * Copyright 2006-2013 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.integration.chunk;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.batch.core.JobInterruptedException;
import org.springframework.batch.core.StepContribution;
import org.springframework.batch.core.step.item.Chunk;
import org.springframework.batch.core.step.item.ChunkProcessor;
import org.springframework.batch.core.step.item.FaultTolerantChunkProcessor;
import org.springframework.batch.core.step.skip.NonSkippableReadException;
import org.springframework.batch.core.step.skip.SkipLimitExceededException;
import org.springframework.batch.core.step.skip.SkipListenerFailedException;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.integration.annotation.MessageEndpoint;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.retry.RetryException;
import org.springframework.util.Assert;

/**
 * A {@link ChunkHandler} based on a {@link ChunkProcessor}. Knows how to distinguish between a processor that is fault
 * tolerant, and one that is not. If the processor is fault tolerant then exceptions can be propagated on the assumption
 * that there will be a roll back and the request will be re-delivered.
 *
 * @author Dave Syer
 * @author Michael Minella
 *
 * @param <S> the type of the items in the chunk to be handled
 */
@MessageEndpoint
public class ChunkProcessorChunkHandler<S> implements ChunkHandler<S>, InitializingBean {

    private static final Log logger = LogFactory.getLog(ChunkProcessorChunkHandler.class);

    private ChunkProcessor<S> chunkProcessor;

    /*
     * (non-Javadoc)
     *
     * @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet()
     */
    public void afterPropertiesSet() throws Exception {
        Assert.notNull(chunkProcessor, "A ChunkProcessor must be provided");
    }

    /**
     * Public setter for the {@link ChunkProcessor}.
     *
     * @param chunkProcessor the chunkProcessor to set
     */
    public void setChunkProcessor(ChunkProcessor<S> chunkProcessor) {
        this.chunkProcessor = chunkProcessor;
    }

    /**
     *
     * @see ChunkHandler#handleChunk(ChunkRequest)
     */
    @ServiceActivator
    public ChunkResponse handleChunk(ChunkRequest<S> chunkRequest) throws Exception {

        if (logger.isDebugEnabled()) {
            logger.debug("Handling chunk: " + chunkRequest);
        }

        StepContribution stepContribution = chunkRequest.getStepContribution();

        Throwable failure = process(chunkRequest, stepContribution);
        if (failure != null) {
            logger.debug("Failed chunk", failure);
            return new ChunkResponse(false, chunkRequest.getSequence(), chunkRequest.getJobId(), stepContribution,
                    failure.getClass().getName() + ": " + failure.getMessage());
        }

        if (logger.isDebugEnabled()) {
            logger.debug("Completed chunk handling with " + stepContribution);
        }
        return new ChunkResponse(true, chunkRequest.getSequence(), chunkRequest.getJobId(), stepContribution);

    }

    /**
     * @param chunkRequest the current request
     * @param stepContribution the step contribution to update
     * @throws Exception if there is a fatal exception
     */
    private Throwable process(ChunkRequest<S> chunkRequest, StepContribution stepContribution) throws Exception {

        Chunk<S> chunk = new Chunk<S>(chunkRequest.getItems());
        Throwable failure = null;
        try {
            chunkProcessor.process(stepContribution, chunk);
        } catch (SkipLimitExceededException e) {
            failure = e;
        } catch (NonSkippableReadException e) {
            failure = e;
        } catch (SkipListenerFailedException e) {
            failure = e;
        } catch (RetryException e) {
            failure = e;
        } catch (JobInterruptedException e) {
            failure = e;
        } catch (Exception e) {
            if (chunkProcessor instanceof FaultTolerantChunkProcessor<?, ?>) {
                // try again...
                throw e;
            } else {
                failure = e;
            }
        }

        return failure;

    }

}