/*
* Copyright 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.jsr.item;
import java.io.Serializable;
import javax.batch.api.chunk.ItemReader;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
/**
* Adapter that wraps an {@link ItemReader} for use by Spring Batch. All calls are delegated as appropriate
* to the corresponding method on the delegate.
*
* @author Michael Minella
* @since 3.0
*/
public class ItemReaderAdapter<T> extends CheckpointSupport implements org.springframework.batch.item.ItemReader<T> {
private static final String CHECKPOINT_KEY = "reader.checkpoint";
private ItemReader delegate;
/**
* @param reader the {@link ItemReader} implementation to delegate to
*/
public ItemReaderAdapter(ItemReader reader) {
super(CHECKPOINT_KEY);
Assert.notNull(reader, "An ItemReader implementation is required");
this.delegate = reader;
setExecutionContextName(ClassUtils.getShortName(delegate.getClass()));
}
/* (non-Javadoc)
* @see org.springframework.batch.item.ItemReader#read()
*/
@SuppressWarnings("unchecked")
@Override
public T read() throws Exception {
return (T) delegate.readItem();
}
/* (non-Javadoc)
* @see org.springframework.batch.jsr.item.CheckpointSupport#doClose()
*/
@Override
protected void doClose() throws Exception{
delegate.close();
}
/* (non-Javadoc)
* @see org.springframework.batch.jsr.item.CheckpointSupport#doCheckpoint()
*/
@Override
protected Serializable doCheckpoint() throws Exception {
return delegate.checkpointInfo();
}
/* (non-Javadoc)
* @see org.springframework.batch.jsr.item.CheckpointSupport#doOpen(java.io.Serializable)
*/
@Override
protected void doOpen(Serializable checkpoint) throws Exception {
delegate.open(checkpoint);
}
}