/*
* Copyright 2008-2013 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.core.partition;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.batch.item.ExecutionContext;
import org.springframework.batch.item.ItemStreamException;
import org.springframework.batch.item.ItemStreamReader;
import org.springframework.batch.item.support.AbstractItemStreamItemReader;
import org.springframework.util.ClassUtils;
/**
* {@link ItemStreamReader} with hard-coded input data.
*/
public class ExampleItemReader extends AbstractItemStreamItemReader<String> {
private Log logger = LogFactory.getLog(getClass());
private String[] input = { "Hello", "world!", "Go", "on", "punk", "make", "my", "day!" };
private int index = 0;
private int min = 0;
private int max = Integer.MAX_VALUE;
public static volatile boolean fail = false;
public ExampleItemReader() {
this.setExecutionContextName(ClassUtils.getShortName(this.getClass()));
}
/**
* @param min the min to set
*/
public void setMin(int min) {
this.min = min;
}
/**
* @param max the max to set
*/
public void setMax(int max) {
this.max = max;
}
/**
* Reads next record from input
*/
@Override
public String read() throws Exception {
if (index >= input.length || index >= max) {
return null;
}
logger.info(String.format("Processing input index=%s, item=%s, in (%s)", index, input[index], this));
if (fail && index == 4) {
synchronized (ExampleItemReader.class) {
if (fail) {
// Only fail once per flag setting...
fail = false;
logger.info(String.format("Throwing exception index=%s, item=%s, in (%s)", index, input[index],
this));
index++;
throw new RuntimeException("Planned failure");
}
}
}
return input[index++];
}
@Override
public void open(ExecutionContext executionContext) throws ItemStreamException {
super.open(executionContext);
index = (int) executionContext.getLong(getExecutionContextKey("POSITION"), min);
}
@Override
public void update(ExecutionContext executionContext) throws ItemStreamException {
super.update(executionContext);
executionContext.putLong(getExecutionContextKey("POSITION"), index);
}
}