package org.springframework.batch.integration.partition;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.batch.item.ExecutionContext;
import org.springframework.batch.item.ItemReader;
import org.springframework.batch.item.ItemStream;
import org.springframework.batch.item.ItemStreamException;
/**
* {@link ItemReader} with hard-coded input data.
*/
public class ExampleItemReader implements ItemReader<String>, ItemStream {
private Log logger = LogFactory.getLog(getClass());
private String[] input = { "Hello", "world!", "Go", "on", "punk", "make", "my", "day!" };
private int index = 0;
public static volatile boolean fail = false;
/**
* Reads next record from input
*/
public String read() throws Exception {
if (index >= input.length) {
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++];
}
public void close() throws ItemStreamException {
}
public void open(ExecutionContext executionContext) throws ItemStreamException {
index = (int) executionContext.getLong("POSITION", 0);
}
public void update(ExecutionContext executionContext) throws ItemStreamException {
executionContext.putLong("POSITION", index);
}
}