IN PROGRESS - issue BATCH-7: Remove transaction synchronization and state management from input/output sources (formerly buffering)

http://jira.springframework.org/browse/BATCH-7

Added ItemStream as base interface for ItemReader/Writer.

spring-batch-execution/src/main/java/org/springframework/batch/execution/tasklet/RestartableItemOrientedTasklet.java

@@ -47,15 +47,15 @@ public class RestartableItemOrientedTasklet extends ItemOrientedTasklet implemen
 		StreamContext itemProviderRestartData = null;
 		StreamContext itemProcessorRestartData = null;
 
-		if (itemProvider instanceof ItemStream) {
-			itemProviderRestartData = ((ItemStream) itemProvider).getRestartData();
+		if (itemProvider != null) {
+			itemProviderRestartData = itemProvider.getRestartData();
+		}
+		if (itemWriter != null) {
+			itemProcessorRestartData = itemWriter.getRestartData();
 		}
 
-		if (itemWriter instanceof ItemStream) {
-			itemProcessorRestartData = ((ItemStream) itemWriter).getRestartData();
-		}
-
-		RestartableItemOrientedTaskletRestartData restartData = new RestartableItemOrientedTaskletRestartData(itemProviderRestartData, itemProcessorRestartData);
+		RestartableItemOrientedTaskletRestartData restartData = new RestartableItemOrientedTaskletRestartData(
+				itemProviderRestartData, itemProcessorRestartData);
 
 		return restartData;
 	}
@@ -76,11 +76,11 @@ public class RestartableItemOrientedTasklet extends ItemOrientedTasklet implemen
 			moduleRestartData = new RestartableItemOrientedTaskletRestartData(data.getProperties());
 		}
 
-		if (itemProvider instanceof ItemStream) {
-			((ItemStream) itemProvider).restoreFrom(moduleRestartData.readerData);
+		if (itemProvider != null) {
+			itemProvider.restoreFrom(moduleRestartData.readerData);
 		}
-		if (itemWriter instanceof ItemStream) {
-			((ItemStream) itemWriter).restoreFrom(moduleRestartData.writerData);
+		if (itemWriter != null) {
+			itemWriter.restoreFrom(moduleRestartData.writerData);
 		}
 	}
 
@@ -100,10 +100,8 @@ public class RestartableItemOrientedTasklet extends ItemOrientedTasklet implemen
 		}
 
 		public RestartableItemOrientedTaskletRestartData(Properties data) {
-			readerData = new GenericStreamContext(PropertiesConverter
-					.stringToProperties(data.getProperty(READER_KEY)));
-			writerData = new GenericStreamContext(PropertiesConverter.stringToProperties(data
-					.getProperty(WRITER_KEY)));
+			readerData = new GenericStreamContext(PropertiesConverter.stringToProperties(data.getProperty(READER_KEY)));
+			writerData = new GenericStreamContext(PropertiesConverter.stringToProperties(data.getProperty(WRITER_KEY)));
 		}
 
 		public Properties getProperties() {
@@ -117,4 +115,20 @@ public class RestartableItemOrientedTasklet extends ItemOrientedTasklet implemen
 			return props;
 		}
 	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.batch.item.ItemStream#close()
+	 */
+	public void close() throws Exception {
+		// no-op
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.batch.item.ItemStream#open()
+	 */
+	public void open() throws Exception {
+		// no-op
+	}
 }

spring-batch-execution/src/test/java/org/springframework/batch/execution/launch/EmptyItemWriter.java

@@ -21,11 +21,11 @@ import java.util.List;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.support.transaction.TransactionAwareProxyFactory;
 import org.springframework.beans.factory.InitializingBean;
 
-public class EmptyItemWriter implements ItemWriter, InitializingBean {
+public class EmptyItemWriter extends AbstractItemWriter implements InitializingBean {
 
 	private boolean failed = false;
 

spring-batch-execution/src/test/java/org/springframework/batch/execution/step/simple/SimpleStepExecutorTests.java

@@ -25,10 +25,10 @@ import java.util.Properties;
 
 import junit.framework.TestCase;
 
-import org.springframework.batch.core.domain.JobSupport;
 import org.springframework.batch.core.domain.JobExecution;
 import org.springframework.batch.core.domain.JobInstance;
 import org.springframework.batch.core.domain.JobParameters;
+import org.springframework.batch.core.domain.JobSupport;
 import org.springframework.batch.core.domain.StepContribution;
 import org.springframework.batch.core.domain.StepExecution;
 import org.springframework.batch.core.domain.StepInstance;
@@ -40,10 +40,10 @@ import org.springframework.batch.execution.scope.StepScope;
 import org.springframework.batch.execution.scope.StepSynchronizationManager;
 import org.springframework.batch.execution.tasklet.ItemOrientedTasklet;
 import org.springframework.batch.item.ItemReader;
-import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.ItemWriter;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.reader.ListItemReader;
+import org.springframework.batch.item.stream.ItemStreamAdapter;
 import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.repeat.ExitStatus;
 import org.springframework.batch.repeat.RepeatContext;
@@ -455,7 +455,7 @@ public class SimpleStepExecutorTests extends TestCase {
 		assertEquals(0, map.size());
 	}
 
-	private class MockRestartableTasklet implements Tasklet, ItemStream {
+	private class MockRestartableTasklet extends ItemStreamAdapter implements Tasklet {
 
 		private boolean getRestartDataCalled = false;
 

spring-batch-execution/src/test/java/org/springframework/batch/execution/tasklet/ItemOrientedTaskletTests.java

@@ -273,7 +273,7 @@ public class ItemOrientedTaskletTests extends TestCase {
 		}
 	}
 
-	private class SkippableItemReader implements KeyedItemReader,
+	private class SkippableItemReader extends AbstractItemReader implements KeyedItemReader,
 			Skippable, StatisticsProvider {
 		public Object read() throws Exception {
 			return itemProvider.read();
@@ -287,11 +287,9 @@ public class ItemOrientedTaskletTests extends TestCase {
 		public Properties getStatistics() {
 			return PropertiesConverter.stringToProperties("foo=bar");
 		}
-		public void close() throws Exception {			
-		}
 	}
 
-	private class SkippableItemWriter implements ItemWriter, Skippable,
+	private class SkippableItemWriter extends AbstractItemWriter implements ItemWriter, Skippable,
 			StatisticsProvider {
 		String props = "foo=bar";
 

spring-batch-execution/src/test/java/org/springframework/batch/execution/tasklet/RestartableItemOrientedTaskletTests.java

@@ -21,10 +21,11 @@ import java.util.Properties;
 import junit.framework.TestCase;
 
 import org.springframework.batch.item.ItemReader;
-import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.ItemWriter;
 import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.reader.AbstractItemReader;
 import org.springframework.batch.item.stream.GenericStreamContext;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.support.PropertiesConverter;
 
 /**
@@ -32,16 +33,16 @@ import org.springframework.batch.support.PropertiesConverter;
  */
 public class RestartableItemOrientedTaskletTests extends TestCase {
 
-	private static class MockProvider implements ItemReader, ItemStream {
+	private static class MockProvider extends AbstractItemReader {
 
 		StreamContext data = new StreamContext() {
 
 			public Properties getProperties() {
 				return PropertiesConverter.stringToProperties("a=b");
 			}
-			
+
 		};
-		
+
 		public Object read() {
 			return null;
 		}
@@ -55,16 +56,9 @@ public class RestartableItemOrientedTaskletTests extends TestCase {
 			assertEquals(this.data.getProperties(), data.getProperties());
 		}
 
-		public boolean recover(Object data, Throwable cause) {
-			return false;
-		}
-
-		public void close() throws Exception {			
-		}
-
 	}
 
-	private static class MockWriter implements ItemWriter, ItemStream {
+	private static class MockWriter extends AbstractItemWriter {
 
 		StreamContext data = new StreamContext() {
 			public Properties getProperties() {
@@ -131,7 +125,7 @@ public class RestartableItemOrientedTaskletTests extends TestCase {
 		// restore from restart data (see asserts in mock classes)
 		module.restoreFrom(data);
 	}
-	
+
 	public void testRestartFromNotRestartable() {
 
 		// create and set up module
@@ -144,7 +138,7 @@ public class RestartableItemOrientedTaskletTests extends TestCase {
 		assertNotNull(data);
 		// restore from restart data (see asserts in mock classes)
 		module.restoreFrom(data);
-		//System.err.println(data.getProperties());
+		// System.err.println(data.getProperties());
 	}
-	
+
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/cursor/HibernateCursorItemReader.java

@@ -26,7 +26,6 @@ import org.hibernate.StatelessSession;
 import org.springframework.batch.io.Skippable;
 import org.springframework.batch.item.ItemReader;
 import org.springframework.batch.item.ItemStream;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.reader.AbstractItemReader;
 import org.springframework.batch.item.stream.GenericStreamContext;
@@ -58,7 +57,7 @@ import org.springframework.util.StringUtils;
  * @author Dave Syer
  */
 public class HibernateCursorItemReader extends AbstractItemReader implements ItemReader, ItemStream,
-		Skippable, InitializingBean, DisposableBean, ResourceLifecycle {
+		Skippable, InitializingBean, DisposableBean {
 
 	private static final String RESTART_DATA_ROW_NUMBER_KEY = ClassUtils
 			.getShortName(HibernateCursorItemReader.class)

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/cursor/JdbcCursorItemReader.java

@@ -33,7 +33,6 @@ import org.springframework.batch.io.Skippable;
 import org.springframework.batch.io.support.AbstractTransactionalIoSource;
 import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.KeyedItemReader;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.statistics.StatisticsProvider;
@@ -117,7 +116,7 @@ import org.springframework.util.StringUtils;
  * @author Peter Zozom
  */
 public class JdbcCursorItemReader extends AbstractTransactionalIoSource
-		implements KeyedItemReader, ResourceLifecycle, DisposableBean,
+		implements KeyedItemReader, DisposableBean,
 		InitializingBean, ItemStream, StatisticsProvider, Skippable {
 
 	private static Log log = LogFactory.getLog(JdbcCursorItemReader.class);

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/driving/DrivingQueryItemReader.java

@@ -21,7 +21,6 @@ import java.util.List;
 import org.springframework.batch.io.support.AbstractTransactionalIoSource;
 import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.KeyedItemReader;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.repeat.synch.BatchTransactionSynchronizationManager;
 import org.springframework.beans.factory.DisposableBean;
@@ -51,7 +50,7 @@ import org.springframework.util.Assert;
  * @since 1.0
  */
 public class DrivingQueryItemReader extends AbstractTransactionalIoSource
-		implements KeyedItemReader, ResourceLifecycle, InitializingBean,
+		implements KeyedItemReader, InitializingBean,
 		DisposableBean, ItemStream {
 
 	private boolean initialized = false;

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/file/FlatFileItemWriter.java

@@ -33,7 +33,6 @@ import org.springframework.batch.io.exception.BatchEnvironmentException;
 import org.springframework.batch.io.support.AbstractTransactionalIoSource;
 import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.ItemWriter;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.item.writer.ItemTransformer;
@@ -61,7 +60,7 @@ import org.springframework.util.Assert;
  * @author Dave Syer
  */
 public class FlatFileItemWriter extends AbstractTransactionalIoSource implements 
-	ItemWriter, ResourceLifecycle, ItemStream, StatisticsProvider, InitializingBean,
+	ItemWriter, ItemStream, StatisticsProvider, InitializingBean,
 	DisposableBean {
 
 	private static final String LINE_SEPARATOR = System.getProperty("line.separator");

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/file/SimpleFlatFileItemReader.java

@@ -31,7 +31,6 @@ import org.springframework.batch.io.file.transform.AbstractLineTokenizer;
 import org.springframework.batch.io.file.transform.DelimitedLineTokenizer;
 import org.springframework.batch.io.file.transform.LineTokenizer;
 import org.springframework.batch.item.ItemReader;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.reader.AbstractItemReader;
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.InitializingBean;
@@ -171,11 +170,10 @@ public class SimpleFlatFileItemReader extends AbstractItemReader implements Item
 	}
 
 	/**
-	 * Close and null out the reader.
-	 * 
-	 * @see ResourceLifecycle
+	 * Close and null out the delegate line reader.
+	 * @throws Exception 
 	 */
-	public void close() {
+	public void close() throws Exception {
 		try {
 			if (reader != null) {
 				log.debug("Closing flat file for reading: "+resource);

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/file/separator/LineReader.java

@@ -16,13 +16,12 @@
 package org.springframework.batch.io.file.separator;
 
 import org.springframework.batch.item.ItemReader;
-import org.springframework.batch.item.ResourceLifecycle;
 
 /**
  * @author Dave Syer
  *
  */
-public interface LineReader extends ResourceLifecycle, ItemReader {
+public interface LineReader extends ItemReader {
 
 	/**
 	 * @return

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/file/separator/ResourceLineReader.java

@@ -27,7 +27,6 @@ import java.util.Iterator;
 
 import org.springframework.batch.io.exception.BatchEnvironmentException;
 import org.springframework.batch.item.ItemReader;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.reader.AbstractItemReader;
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.core.io.Resource;
@@ -56,7 +55,7 @@ import org.springframework.util.Assert;
  * @author Dave Syer
  * @author Rob Harrop
  */
-public class ResourceLineReader extends AbstractItemReader implements LineReader, ResourceLifecycle, ItemReader,
+public class ResourceLineReader extends AbstractItemReader implements LineReader, ItemReader,
 		DisposableBean {
 
 	private static final Collection DEFAULT_COMMENTS = Collections.singleton("#");

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/support/HibernateAwareItemWriter.java

@@ -20,6 +20,7 @@ import java.util.Set;
 
 import org.hibernate.SessionFactory;
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.stream.ItemStreamAdapter;
 import org.springframework.batch.repeat.ExitStatus;
 import org.springframework.batch.repeat.RepeatContext;
 import org.springframework.batch.repeat.RepeatInterceptor;
@@ -44,7 +45,7 @@ import org.springframework.util.Assert;
  * @author Dave Syer
  * 
  */
-public class HibernateAwareItemWriter implements ItemWriter, RepeatInterceptor,
+public class HibernateAwareItemWriter extends ItemStreamAdapter implements ItemWriter, RepeatInterceptor,
 		InitializingBean {
 
 	/**

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/xml/StaxEventItemReader.java

@@ -19,7 +19,6 @@ import org.springframework.batch.io.xml.stax.FragmentEventReader;
 import org.springframework.batch.io.xml.stax.TransactionalEventReader;
 import org.springframework.batch.item.ItemReader;
 import org.springframework.batch.item.ItemStream;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.reader.AbstractItemReader;
 import org.springframework.batch.item.stream.GenericStreamContext;
@@ -43,7 +42,7 @@ import org.springframework.util.Assert;
  * 
  * @author Robert Kasanicky
  */
-public class StaxEventItemReader extends AbstractItemReader implements ItemReader, ResourceLifecycle,
+public class StaxEventItemReader extends AbstractItemReader implements ItemReader,
 		Skippable, ItemStream, StatisticsProvider, InitializingBean, DisposableBean {
 
 	public static final String READ_COUNT_STATISTICS_NAME = "StaxEventReaderItemReader.readCount";

spring-batch-infrastructure/src/main/java/org/springframework/batch/io/xml/StaxEventItemWriter.java

@@ -18,7 +18,6 @@ import org.springframework.batch.io.support.FileUtils;
 import org.springframework.batch.io.xml.stax.NoStartEndDocumentStreamWriter;
 import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.ItemWriter;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.repeat.synch.BatchTransactionSynchronizationManager;
@@ -42,7 +41,7 @@ import org.springframework.util.CollectionUtils;
  * @author Peter Zozom
  *
  */
-public class StaxEventItemWriter implements ItemWriter, ResourceLifecycle, ItemStream,
+public class StaxEventItemWriter implements ItemWriter, ItemStream,
 		StatisticsProvider, InitializingBean, DisposableBean {
 
 	// default encoding

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/ItemReader.java

@@ -38,7 +38,7 @@ import org.springframework.batch.item.reader.AbstractItemReader;
  * @author Lucas Ward
  * @since 1.0
  */
-public interface ItemReader {
+public interface ItemReader extends ItemStream {
 
 	/**
 	 * Reads a piece of input data and advance to the next one. Implementations
@@ -51,9 +51,4 @@ public interface ItemReader {
 	 */
 	Object read() throws Exception;
 
-	/**
-	 * Close the reader, freeing any resources that may have been allocated
-	 * since the first call to read().
-	 */
-	void close() throws Exception;
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/ItemStream.java

@@ -35,6 +35,16 @@ package org.springframework.batch.item;
  * 
  */
 public interface ItemStream {
+	
+	void open() throws Exception;
+	
+	/**
+	 * Close the reader, freeing any resources that may have been allocated
+	 * since the first call to read().
+	 * 
+	 * @throws Exception if an underlying resource is unavailable
+	 */
+	void close() throws Exception;
 
 	/**
 	 * Get {@link StreamContext} representing this object's current state.

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/ItemWriter.java

@@ -25,7 +25,7 @@ package org.springframework.batch.item;
  * @author Dave Syer
  * @author Lucas Ward
  */
-public interface ItemWriter {
+public interface ItemWriter extends ItemStream {
 
 	/**
 	 * Process the supplied data element. Will be called multiple times during a
@@ -38,10 +38,4 @@ public interface ItemWriter {
 	 */
 	public void write(Object item) throws Exception;
 	
-	/**
-	 * Close the writer, allowing all allocated resources to be cleaned up.
-	 * 
-	 * @throws Exception
-	 */
-	void close() throws Exception;
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/ResourceLifecycle.java

@@ -1,37 +0,0 @@
-/*
- * 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.item;
-
-/**
- * Common interface for classes that require initialisation before they can be
- * used and need to free resources after they are no longer used.
- */
-public interface ResourceLifecycle {
-	/**
-	 * This method should be invoked by clients at the start of processing to
-	 * allow initialisation of resources.
-	 * 
-	 */
-	public void open();
-
-	/**
-	 * This method should be invoked by clients after the completion of each
-	 * step and the implementing class should close all managed resources.
-	 * 
-	 */
-	public void close();
-}

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/reader/AbstractItemReader.java

@@ -17,19 +17,13 @@
 package org.springframework.batch.item.reader;
 
 import org.springframework.batch.item.ItemReader;
+import org.springframework.batch.item.stream.ItemStreamAdapter;
 
 /**
  * Base class for {@link ItemReader} implementations.
  * @author Dave Syer
  *
  */
-public abstract class AbstractItemReader implements ItemReader {
-	
-	/**
-	 * Do nothing.
-	 * @see org.springframework.batch.item.ItemReader#close()
-	 */
-	public void close() throws Exception {		
-	}
+public abstract class AbstractItemReader extends ItemStreamAdapter implements ItemReader {
 
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/reader/ItemReaderAdapter.java

@@ -16,7 +16,11 @@
 
 package org.springframework.batch.item.reader;
 
+import java.util.Properties;
+
 import org.springframework.batch.item.ItemReader;
+import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.support.AbstractMethodInvokingDelegator;
 
 /**
@@ -35,10 +39,33 @@ public class ItemReaderAdapter extends AbstractMethodInvokingDelegator implement
 
 	/**
 	 * Do nothing.
-	 * 
-	 * @see org.springframework.batch.item.ItemReader#close()
+	 * @see org.springframework.batch.item.ItemStream#open()
+	 */
+	public void open() throws Exception {
+		// no-op
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#close()
 	 */
 	public void close() throws Exception {
+		// no-op
+	}
+
+	/**
+	 * Return empty {@link StreamContext}.
+	 * @see org.springframework.batch.item.ItemStream#getRestartData()
+	 */
+	public StreamContext getRestartData() {
+		return new GenericStreamContext(new Properties());
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#restoreFrom(org.springframework.batch.item.StreamContext)
+	 */
+	public void restoreFrom(StreamContext data) {
 		
 	}
 

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/writer/AbstractItemWriter.java

@@ -1,31 +0,0 @@
-/*
- * Copyright 2006-2008 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.item.writer;
-
-import org.springframework.batch.item.ItemWriter;
-
-/**
- * Abstract {@link ItemWriter} that allows for base classes to only
- * implement the close method if they need it.
- * 
- * @author Lucas Ward
- *
- */
-public abstract class AbstractItemWriter implements ItemWriter{
-
-	public void close() throws Exception {
-	}
-}

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/writer/CompositeItemWriter.java

@@ -11,13 +11,14 @@ import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.ItemWriter;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.stream.GenericStreamContext;
+import org.springframework.batch.item.stream.ItemStreamAdapter;
 
 /**
  * Runs a collection of ItemProcessors in fixed-order sequence.
  * 
  * @author Robert Kasanicky
  */
-public class CompositeItemWriter implements ItemWriter, ItemStream {
+public class CompositeItemWriter extends ItemStreamAdapter implements ItemWriter, ItemStream {
 
 	private static final String SEPARATOR = "#";
 
@@ -38,13 +39,8 @@ public class CompositeItemWriter implements ItemWriter, ItemStream {
 	 */
 	public StreamContext getRestartData() {
 		Properties props = createCompoundProperties(new PropertiesExtractor() {
-			public Properties extractProperties(Object o) {
-				if (o instanceof ItemStream) {
-					return ((ItemStream) o).getRestartData().getProperties();
-				}
-				else {
-					return null;
-				}
+			public Properties extractProperties(ItemStream o) {
+					return o.getRestartData().getProperties();
 			}
 		});
 		return new GenericStreamContext(props);
@@ -105,7 +101,7 @@ public class CompositeItemWriter implements ItemWriter, ItemStream {
 		Properties stats = new Properties();
 		int index = 0;
 		for (Iterator iterator = delegates.listIterator(); iterator.hasNext();) {
-			Properties writerStats = extractor.extractProperties(iterator.next());
+			Properties writerStats = extractor.extractProperties((ItemStream) iterator.next());
 			if (writerStats != null) {
 				for (Iterator iterator2 = writerStats.entrySet().iterator(); iterator2.hasNext();) {
 					Map.Entry entry = (Map.Entry) iterator2.next();
@@ -123,7 +119,7 @@ public class CompositeItemWriter implements ItemWriter, ItemStream {
 	 * null.
 	 */
 	private interface PropertiesExtractor {
-		Properties extractProperties(Object o);
+		Properties extractProperties(ItemStream o);
 	}
 	
 	public void close() throws Exception {

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/writer/DelegatingItemWriter.java

@@ -7,6 +7,7 @@ import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.ItemWriter;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.stream.GenericStreamContext;
+import org.springframework.batch.item.stream.ItemStreamAdapter;
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.util.Assert;
 
@@ -17,7 +18,7 @@ import org.springframework.util.Assert;
  * @author Dave Syer
  * @author Robert Kasanicky
  */
-public class DelegatingItemWriter implements ItemWriter, ItemStream, Skippable, InitializingBean {
+public class DelegatingItemWriter extends ItemStreamAdapter implements ItemWriter, Skippable, InitializingBean {
 
 	private ItemWriter writer;
 

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/writer/ItemWriterAdapter.java

@@ -16,7 +16,11 @@
 
 package org.springframework.batch.item.writer;
 
+import java.util.Properties;
+
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.support.AbstractMethodInvokingDelegator;
 
 
@@ -34,13 +38,35 @@ public class ItemWriterAdapter extends AbstractMethodInvokingDelegator implement
     	invokeDelegateMethodWithArgument(item);
     }
 
-    /*
-     * No-op, can't call more than one method.
-     * 
-     * (non-Javadoc)
-     * @see org.springframework.batch.item.ItemWriter#close()
-     */
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#open()
+	 */
+	public void open() throws Exception {
+		// no-op
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#close()
+	 */
 	public void close() throws Exception {
+		// no-op
+	}
+
+	/**
+	 * Return empty {@link StreamContext}.
+	 * @see org.springframework.batch.item.ItemStream#getRestartData()
+	 */
+	public StreamContext getRestartData() {
+		return new GenericStreamContext(new Properties());
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#restoreFrom(org.springframework.batch.item.StreamContext)
+	 */
+	public void restoreFrom(StreamContext data) {
 		
 	}
 	

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/writer/PropertyExtractingDelegatingItemWriter.java

@@ -16,7 +16,11 @@
 
 package org.springframework.batch.item.writer;
 
+import java.util.Properties;
+
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.support.AbstractMethodInvokingDelegator;
 import org.springframework.beans.BeanWrapper;
 import org.springframework.beans.BeanWrapperImpl;
@@ -66,7 +70,35 @@ public class PropertyExtractingDelegatingItemWriter extends AbstractMethodInvoki
 		this.fieldsUsedAsTargetMethodArguments = fieldsUsedAsMethodArguments;
 	}
 
-
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#open()
+	 */
+	public void open() throws Exception {
+		// no-op
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#close()
+	 */
 	public void close() throws Exception {
+		// no-op
+	}
+
+	/**
+	 * Return empty {@link StreamContext}.
+	 * @see org.springframework.batch.item.ItemStream#getRestartData()
+	 */
+	public StreamContext getRestartData() {
+		return new GenericStreamContext(new Properties());
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#restoreFrom(org.springframework.batch.item.StreamContext)
+	 */
+	public void restoreFrom(StreamContext data) {
+		
 	}
 }

spring-batch-infrastructure/src/test/java/org/springframework/batch/io/support/HibernateAwareItemWriterTests.java

@@ -22,7 +22,7 @@ import java.util.Map;
 
 import junit.framework.TestCase;
 
-import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.repeat.ExitStatus;
 import org.springframework.batch.repeat.RepeatContext;
 import org.springframework.batch.repeat.RepeatInterceptor;
@@ -41,12 +41,13 @@ public class HibernateAwareItemWriterTests extends TestCase {
 		public void flush() throws DataAccessException {
 			list.add("flush");
 		}
+
 		public void clear() {
-			list.add("clear");				
+			list.add("clear");
 		};
 	}
 
-	private class StubItemWriter implements ItemWriter, RepeatInterceptor {
+	private class StubItemWriter extends AbstractItemWriter implements RepeatInterceptor {
 		public void write(Object item) {
 			list.add(item);
 		}
@@ -70,13 +71,10 @@ public class HibernateAwareItemWriterTests extends TestCase {
 		public void open(RepeatContext context) {
 			list.add(context);
 		}
-
-		public void close() throws Exception {
-		}
 	}
 
 	HibernateAwareItemWriter writer = new HibernateAwareItemWriter();
-	
+
 	final List list = new ArrayList();
 
 	private RepeatContextSupport context;
@@ -93,15 +91,16 @@ public class HibernateAwareItemWriterTests extends TestCase {
 		writer.setHibernateTemplate(new HibernateTemplateWrapper());
 		list.clear();
 	}
-	
-	/* (non-Javadoc)
+
+	/*
+	 * (non-Javadoc)
 	 * @see junit.framework.TestCase#tearDown()
 	 */
 	protected void tearDown() throws Exception {
 		Map map = TransactionSynchronizationManager.getResourceMap();
 		for (Iterator iterator = map.keySet().iterator(); iterator.hasNext();) {
 			String key = (String) iterator.next();
-			TransactionSynchronizationManager.unbindResource(key);			
+			TransactionSynchronizationManager.unbindResource(key);
 		}
 	}
 
@@ -116,10 +115,10 @@ public class HibernateAwareItemWriterTests extends TestCase {
 		try {
 			writer.afterPropertiesSet();
 			fail("Expected IllegalArgumentException");
-		} catch (IllegalArgumentException e) {
+		}
+		catch (IllegalArgumentException e) {
 			// expected
-			assertTrue("Wrong message for exception: " + e.getMessage(), e
-					.getMessage().indexOf("delegate") >= 0);
+			assertTrue("Wrong message for exception: " + e.getMessage(), e.getMessage().indexOf("delegate") >= 0);
 		}
 	}
 
@@ -136,7 +135,7 @@ public class HibernateAwareItemWriterTests extends TestCase {
 	/**
 	 * Test method for
 	 * {@link org.springframework.batch.io.support.HibernateAwareItemWriter#write(java.lang.Object)}.
-	 * @throws Exception 
+	 * @throws Exception
 	 */
 	public void testWrite() throws Exception {
 		writer.write("foo");
@@ -158,7 +157,8 @@ public class HibernateAwareItemWriterTests extends TestCase {
 		try {
 			writer.close(context);
 			fail("Expected RuntimeException");
-		} catch (RuntimeException e) {
+		}
+		catch (RuntimeException e) {
 			assertEquals("bar", e.getMessage());
 		}
 		assertEquals(2, list.size());
@@ -169,7 +169,7 @@ public class HibernateAwareItemWriterTests extends TestCase {
 	/**
 	 * Test method for
 	 * {@link org.springframework.batch.io.support.HibernateAwareItemWriter#write(java.lang.Object)}.
-	 * @throws Exception 
+	 * @throws Exception
 	 */
 	public void testWriteAndCloseWithFailure() throws Exception {
 		final RuntimeException ex = new RuntimeException("bar");
@@ -182,7 +182,8 @@ public class HibernateAwareItemWriterTests extends TestCase {
 		try {
 			writer.close(context);
 			fail("Expected RuntimeException");
-		} catch (RuntimeException e) {
+		}
+		catch (RuntimeException e) {
 			assertEquals("bar", e.getMessage());
 		}
 		assertEquals(3, list.size());

spring-batch-infrastructure/src/test/java/org/springframework/batch/item/writer/CompositeItemWriterTests.java

@@ -8,11 +8,10 @@ import java.util.Properties;
 import junit.framework.TestCase;
 
 import org.easymock.MockControl;
-import org.springframework.batch.item.ItemStream;
 import org.springframework.batch.item.ItemWriter;
 import org.springframework.batch.item.StreamContext;
 import org.springframework.batch.item.stream.GenericStreamContext;
-import org.springframework.batch.item.writer.CompositeItemWriter;
+import org.springframework.batch.item.stream.ItemStreamAdapter;
 import org.springframework.batch.statistics.StatisticsProvider;
 
 /**
@@ -62,14 +61,9 @@ public class CompositeItemWriterTests extends TestCase {
 	 * All Restartable processors should be restarted, not-Restartable processors should be ignored.
 	 */
 	public void testRestart() {
-		//this mock with undefined behavior makes sure not-Restartable processor is ignored
-		MockControl p1c = MockControl.createStrictControl(ItemWriter.class);
-		final ItemWriter p1 = (ItemWriter) p1c.getMock();
-		
 		final ItemWriter p2 = new ItemWriterStub();
 		final ItemWriter p3 = new ItemWriterStub();
 		List itemProcessors = new ArrayList(){{
-			add(p1);
 			add(p2);
 			add(p3);
 		}};
@@ -120,7 +114,7 @@ public class CompositeItemWriterTests extends TestCase {
 	 * Stub for testing restart. Checks the restart data received is the same that was returned by
 	 * <code>getRestartData()</code>
 	 */
-	private static class ItemWriterStub implements ItemWriter, ItemStream, StatisticsProvider {
+	private static class ItemWriterStub extends ItemStreamAdapter implements ItemWriter, StatisticsProvider {
 		
 		private static final String RESTART_KEY = "restartData";
 		private static final String STATS_KEY = "stats";

spring-batch-infrastructure/src/test/java/org/springframework/batch/repeat/support/AsynchronousRepeatTests.java

@@ -19,9 +19,9 @@ package org.springframework.batch.repeat.support;
 import java.util.HashSet;
 import java.util.Set;
 
+import org.springframework.batch.repeat.ExitStatus;
 import org.springframework.batch.repeat.RepeatCallback;
 import org.springframework.batch.repeat.RepeatContext;
-import org.springframework.batch.repeat.ExitStatus;
 import org.springframework.batch.repeat.callback.ItemReaderRepeatCallback;
 import org.springframework.core.task.SimpleAsyncTaskExecutor;
 

spring-batch-samples/src/main/java/org/springframework/batch/sample/dao/FlatFileCustomerCreditWriter.java

@@ -17,7 +17,6 @@
 package org.springframework.batch.sample.dao;
 
 import org.springframework.batch.item.ItemWriter;
-import org.springframework.batch.item.ResourceLifecycle;
 import org.springframework.batch.sample.domain.CustomerCredit;
 import org.springframework.beans.factory.DisposableBean;
 
@@ -56,17 +55,13 @@ public class FlatFileCustomerCreditWriter implements CustomerCreditDao,
 		this.outputSource = outputSource;
 	}
 
-	public void open() {
-		if (outputSource instanceof ResourceLifecycle) {
-			((ResourceLifecycle) outputSource).open();
-		}
+	public void open() throws Exception {
+		outputSource.open();
 		opened = true;
 	}
 
-	public void close() {
-		if (outputSource instanceof ResourceLifecycle) {
-			((ResourceLifecycle) outputSource).close();
-		}
+	public void close() throws Exception {
+		outputSource.close();
 	}
 
 	/*

spring-batch-samples/src/main/java/org/springframework/batch/sample/dao/JdbcGameDao.java

@@ -1,6 +1,10 @@
 package org.springframework.batch.sample.dao;
 
+import java.util.Properties;
+
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.sample.domain.Game;
 import org.springframework.jdbc.core.support.JdbcDaoSupport;
 import org.springframework.util.Assert;
@@ -34,7 +38,36 @@ public class JdbcGameDao extends JdbcDaoSupport implements ItemWriter {
 		this.getJdbcTemplate().update(INSERT_GAME, args);
 	}
 
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#open()
+	 */
+	public void open() throws Exception {
+		// no-op
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#close()
+	 */
 	public void close() throws Exception {
+		// no-op
+	}
+
+	/**
+	 * Return empty {@link StreamContext}.
+	 * @see org.springframework.batch.item.ItemStream#getRestartData()
+	 */
+	public StreamContext getRestartData() {
+		return new GenericStreamContext(new Properties());
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#restoreFrom(org.springframework.batch.item.StreamContext)
+	 */
+	public void restoreFrom(StreamContext data) {
+		
 	}
 
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/dao/JdbcPlayerSummaryDao.java

@@ -1,6 +1,10 @@
 package org.springframework.batch.sample.dao;
 
+import java.util.Properties;
+
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.sample.domain.PlayerSummary;
 import org.springframework.jdbc.core.support.JdbcDaoSupport;
 import org.springframework.util.Assert;
@@ -28,7 +32,36 @@ public class JdbcPlayerSummaryDao extends JdbcDaoSupport implements ItemWriter {
 		getJdbcTemplate().update(INSERT_SUMMARY, args);
 	}
 
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#open()
+	 */
+	public void open() throws Exception {
+		// no-op
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#close()
+	 */
 	public void close() throws Exception {
+		// no-op
+	}
+
+	/**
+	 * Return empty {@link StreamContext}.
+	 * @see org.springframework.batch.item.ItemStream#getRestartData()
+	 */
+	public StreamContext getRestartData() {
+		return new GenericStreamContext(new Properties());
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#restoreFrom(org.springframework.batch.item.StreamContext)
+	 */
+	public void restoreFrom(StreamContext data) {
+		
 	}
 
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/reader/StagingItemReader.java

@@ -5,6 +5,7 @@ import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Properties;
 
 import org.apache.commons.lang.SerializationUtils;
 import org.apache.commons.logging.Log;
@@ -12,7 +13,8 @@ import org.apache.commons.logging.LogFactory;
 import org.springframework.batch.execution.scope.StepContext;
 import org.springframework.batch.execution.scope.StepContextAware;
 import org.springframework.batch.item.KeyedItemReader;
-import org.springframework.batch.item.ResourceLifecycle;
+import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.batch.repeat.synch.BatchTransactionSynchronizationManager;
 import org.springframework.batch.sample.item.writer.StagingItemWriter;
 import org.springframework.beans.factory.DisposableBean;
@@ -26,7 +28,7 @@ import org.springframework.transaction.support.TransactionSynchronizationAdapter
 import org.springframework.transaction.support.TransactionSynchronizationManager;
 import org.springframework.util.Assert;
 
-public class StagingItemReader extends JdbcDaoSupport implements KeyedItemReader, ResourceLifecycle, DisposableBean,
+public class StagingItemReader extends JdbcDaoSupport implements KeyedItemReader, DisposableBean,
 		StepContextAware {
 
 	// Key for buffer in transaction synchronization manager
@@ -250,5 +252,21 @@ public class StagingItemReader extends JdbcDaoSupport implements KeyedItemReader
 			return "list=" + list + "; iter.hasNext()=" + iter.hasNext();
 		}
 	}
+	
+	/**
+	 * Return empty {@link StreamContext}.
+	 * @see org.springframework.batch.item.ItemStream#getRestartData()
+	 */
+	public StreamContext getRestartData() {
+		return new GenericStreamContext(new Properties());
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#restoreFrom(org.springframework.batch.item.StreamContext)
+	 */
+	public void restoreFrom(StreamContext data) {
+		
+	}
 
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/CustomerCreditIncreaseWriter.java

@@ -3,6 +3,7 @@ package org.springframework.batch.sample.item.writer;
 import java.math.BigDecimal;
 
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.sample.dao.CustomerCreditDao;
 import org.springframework.batch.sample.domain.CustomerCredit;
 
@@ -11,7 +12,7 @@ import org.springframework.batch.sample.domain.CustomerCredit;
  * 
  * @author Robert Kasanicky
  */
-public class CustomerCreditIncreaseWriter implements ItemWriter {
+public class CustomerCreditIncreaseWriter extends AbstractItemWriter implements ItemWriter {
 
 	public static final BigDecimal FIXED_AMOUNT = new BigDecimal(1000);
 	
@@ -34,6 +35,9 @@ public class CustomerCreditIncreaseWriter implements ItemWriter {
 		customerCreditDao.writeCredit(customerCredit);
 	}
 
+	public void open() throws Exception {
+	}
+
 	public void close() throws Exception {
 	}
 

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/CustomerCreditUpdateWriter.java

@@ -17,12 +17,13 @@
 package org.springframework.batch.sample.item.writer;
 
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.sample.dao.CustomerCreditDao;
 import org.springframework.batch.sample.domain.CustomerCredit;
 
 
 
-public class CustomerCreditUpdateWriter implements ItemWriter {
+public class CustomerCreditUpdateWriter extends AbstractItemWriter implements ItemWriter {
     private double creditFilter = 800;
     private CustomerCreditDao dao;
 

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/CustomerUpdateWriter.java

@@ -17,6 +17,7 @@
 package org.springframework.batch.sample.item.writer;
 
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.sample.dao.JdbcCustomerDebitWriter;
 import org.springframework.batch.sample.domain.CustomerDebit;
 import org.springframework.batch.sample.domain.Trade;
@@ -27,7 +28,7 @@ import org.springframework.batch.sample.domain.Trade;
  * 
  * @author Robert Kasanicky
  */
-public class CustomerUpdateWriter implements ItemWriter {
+public class CustomerUpdateWriter extends AbstractItemWriter implements ItemWriter {
     private JdbcCustomerDebitWriter dao;
 
     public void write(Object data) {
@@ -42,9 +43,6 @@ public class CustomerUpdateWriter implements ItemWriter {
         this.dao = outputSource;
     }
 
-	public void close() {
-	}
-
 	public void init() {
 	}
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/DummyItemWriter.java

@@ -15,19 +15,16 @@
  */
 package org.springframework.batch.sample.item.writer;
 
-import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 
 /**
  * @author Dave Syer
  *
  */
-public class DummyItemWriter implements ItemWriter {
+public class DummyItemWriter extends AbstractItemWriter  {
 
 	public void write(Object item) throws Exception {
 		// NO-OP
 	}
 
-	public void close() throws Exception {
-	}
-
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/PersonWriter.java

@@ -18,12 +18,12 @@ package org.springframework.batch.sample.item.writer;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.sample.domain.Person;
 
 
 
-public class PersonWriter implements ItemWriter {
+public class PersonWriter extends AbstractItemWriter  {
     private static Log log = LogFactory.getLog(PersonWriter.class);
  
     public void write(Object data) {
@@ -36,9 +36,6 @@ public class PersonWriter implements ItemWriter {
         log.debug("Processing: " + data);
     }
 
-	public void close() {
-	}
-
 	public void init() {
 	}
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/PlayerItemWriter.java

@@ -1,10 +1,10 @@
 package org.springframework.batch.sample.item.writer;
 
-import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.sample.dao.PlayerDao;
 import org.springframework.batch.sample.domain.Player;
 
-public class PlayerItemWriter implements ItemWriter {
+public class PlayerItemWriter extends AbstractItemWriter {
 
 	PlayerDao playerDao;
 	
@@ -16,6 +16,4 @@ public class PlayerItemWriter implements ItemWriter {
 		this.playerDao = playerDao;
 	}
 
-	public void close() throws Exception {
-	}
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/StagingItemWriter.java

@@ -2,11 +2,14 @@ package org.springframework.batch.sample.item.writer;
 
 import java.io.Serializable;
 import java.sql.Types;
+import java.util.Properties;
 
 import org.apache.commons.lang.SerializationUtils;
 import org.springframework.batch.execution.scope.StepContext;
 import org.springframework.batch.execution.scope.StepContextAware;
 import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.StreamContext;
+import org.springframework.batch.item.stream.GenericStreamContext;
 import org.springframework.jdbc.core.support.JdbcDaoSupport;
 import org.springframework.jdbc.support.incrementer.DataFieldMaxValueIncrementer;
 import org.springframework.util.Assert;
@@ -73,7 +76,37 @@ public class StagingItemWriter extends JdbcDaoSupport implements
 						new int[] { Types.BIGINT, Types.BIGINT, Types.BLOB, Types.CHAR});
 	}
 
+
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#open()
+	 */
+	public void open() throws Exception {
+		// no-op
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#close()
+	 */
 	public void close() throws Exception {
+		// no-op
+	}
+
+	/**
+	 * Return empty {@link StreamContext}.
+	 * @see org.springframework.batch.item.ItemStream#getRestartData()
+	 */
+	public StreamContext getRestartData() {
+		return new GenericStreamContext(new Properties());
+	}
+	
+	/**
+	 * Do nothing.
+	 * @see org.springframework.batch.item.ItemStream#restoreFrom(org.springframework.batch.item.StreamContext)
+	 */
+	public void restoreFrom(StreamContext data) {
+		
 	}
 
 }

spring-batch-samples/src/main/java/org/springframework/batch/sample/item/writer/TradeWriter.java

@@ -18,13 +18,13 @@ package org.springframework.batch.sample.item.writer;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.writer.AbstractItemWriter;
 import org.springframework.batch.sample.dao.TradeDao;
 import org.springframework.batch.sample.domain.Trade;
 
 
 
-public class TradeWriter implements ItemWriter {
+public class TradeWriter extends AbstractItemWriter {
     private static Log log = LogFactory.getLog(TradeWriter.class);
     private TradeDao dao;
     

spring-batch-samples/src/test/java/org/springframework/batch/sample/dao/FlatFileCustomerCreditWriterTests.java

@@ -2,12 +2,11 @@ package org.springframework.batch.sample.dao;
 
 import java.math.BigDecimal;
 
-import org.springframework.batch.item.ItemWriter;
-import org.springframework.batch.item.ResourceLifecycle;
-import org.springframework.batch.sample.domain.CustomerCredit;
+import junit.framework.TestCase;
 
 import org.easymock.MockControl;
-import junit.framework.TestCase;
+import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.sample.domain.CustomerCredit;
 
 public class FlatFileCustomerCreditWriterTests extends TestCase {
 
@@ -27,7 +26,7 @@ public class FlatFileCustomerCreditWriterTests extends TestCase {
 		writer.setOutputSource(output);
 	}
 
-	public void testOpen() {
+	public void testOpen() throws Exception {
 		
 		//set-up outputSource mock
 		output.open();
@@ -75,7 +74,7 @@ public class FlatFileCustomerCreditWriterTests extends TestCase {
 		outputControl.verify();
 	}
 	
-	private interface ResourceLifecycleItemWriter extends ItemWriter, ResourceLifecycle {
+	private interface ResourceLifecycleItemWriter extends ItemWriter {
 		
 	}
 }