RESOLVED - BATCH-1243: Expose the current resource of MultiResourceItemReader

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

@@ -46,7 +46,7 @@ import org.springframework.util.ClassUtils;
  * @author Robert Kasanicky
  */
 public class MultiResourceItemReader<T> implements ItemReader<T>, ItemStream {
-	
+
 	private static final Log logger = LogFactory.getLog(MultiResourceItemReader.class);
 
 	private final ExecutionContextUserSupport executionContextUserSupport = new ExecutionContextUserSupport();
@@ -58,7 +58,7 @@ public class MultiResourceItemReader<T> implements ItemReader<T>, ItemStream {
 	private MultiResourceIndex index = new MultiResourceIndex();
 
 	private boolean saveState = true;
-	
+
 	// signals there are no resources to read -> just return null on first read
 	private boolean noInput;
 
@@ -85,7 +85,7 @@ public class MultiResourceItemReader<T> implements ItemReader<T>, ItemStream {
 		if (noInput) {
 			return null;
 		}
-		
+
 		T item;
 		item = readNextItem();
 		index.incrementItemCount();
@@ -96,6 +96,7 @@ public class MultiResourceItemReader<T> implements ItemReader<T>, ItemStream {
 	/**
 	 * Use the delegate to read the next item, jump to next resource if current
 	 * one is exhausted. Items are appended to the buffer.
+	 * 
 	 * @return next item from input
 	 */
 	private T readNextItem() throws Exception {
@@ -137,7 +138,7 @@ public class MultiResourceItemReader<T> implements ItemReader<T>, ItemStream {
 	public void open(ExecutionContext executionContext) throws ItemStreamException {
 
 		Assert.notNull(resources, "Resources must be set");
-		
+
 		noInput = false;
 		if (resources.length == 0) {
 			logger.warn("No resources to read");
@@ -192,7 +193,7 @@ public class MultiResourceItemReader<T> implements ItemReader<T>, ItemStream {
 
 	/**
 	 * @param comparator used to order the injected resources, by default
-	 * compares {@link Resource#getFilename()} values.
+	 *        compares {@link Resource#getFilename()} values.
 	 */
 	public void setComparator(Comparator<Resource> comparator) {
 		this.comparator = comparator;
@@ -205,6 +206,13 @@ public class MultiResourceItemReader<T> implements ItemReader<T>, ItemStream {
 		this.resources = resources;
 	}
 
+	public Resource getCurrentResource() {
+		if (index.currentResource >= resources.length) {
+			return null;
+		}
+		return resources[index.currentResource];
+	}
+
 	/**
 	 * Facilitates keeping track of the position within multi-resource input.
 	 */

spring-batch-infrastructure/src/test/java/org/springframework/batch/item/file/MultiResourceItemReaderIntegrationTests.java

@@ -35,7 +35,7 @@ public class MultiResourceItemReaderIntegrationTests extends TestCase {
 	 * Setup the tested reader to read from the test resources.
 	 */
 	protected void setUp() throws Exception {
-		
+
 		itemReader.setLineMapper(new PassThroughLineMapper());
 
 		tested.setDelegate(itemReader);
@@ -67,6 +67,33 @@ public class MultiResourceItemReaderIntegrationTests extends TestCase {
 		tested.close();
 	}
 
+	public void testGetCurrentResource() throws Exception {
+
+		tested.open(ctx);
+
+		assertSame(r1, tested.getCurrentResource());
+		assertEquals("1", tested.read());
+		assertSame(r1, tested.getCurrentResource());
+		assertEquals("2", tested.read());
+		assertSame(r1, tested.getCurrentResource());
+		assertEquals("3", tested.read());
+		assertSame(r1, tested.getCurrentResource());
+		assertEquals("4", tested.read());
+		assertSame(r2, tested.getCurrentResource());
+		assertEquals("5", tested.read());
+		assertSame(r2, tested.getCurrentResource());
+		assertEquals("6", tested.read());
+		assertSame(r4, tested.getCurrentResource());
+		assertEquals("7", tested.read());
+		assertSame(r5, tested.getCurrentResource());
+		assertEquals("8", tested.read());
+		assertSame(r5, tested.getCurrentResource());
+		assertEquals(null, tested.read());
+		assertSame(null, tested.getCurrentResource());
+
+		tested.close();
+	}
+
 	public void testRestartWhenStateNotSaved() throws Exception {
 
 		tested.setSaveState(false);
@@ -205,7 +232,7 @@ public class MultiResourceItemReaderIntegrationTests extends TestCase {
 	public void testNoResourcesFound() throws Exception {
 		tested.setResources(new Resource[] {});
 		tested.open(ctx);
-		
+
 		assertNull(tested.read());
 	}