IN PROGRESS - BATCH-826: Create callback for header and footer reading in xml and flat files

added header callback to FFIR

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

@@ -90,10 +90,19 @@ public class FlatFileItemReader<T> extends AbstractItemReaderItemStream<T> imple
 
 	private BufferedReader reader;
 
+	private LineCallbackHandler headerCallback;
+
 	public FlatFileItemReader() {
 		setName(ClassUtils.getShortName(FlatFileItemReader.class));
 	}
 
+	/**
+	 * headerCallback will be passed the header line before any items are read.
+	 */
+	public void setHeaderCallback(LineCallbackHandler headerCallback) {
+		this.headerCallback = headerCallback;
+	}
+
 	/**
 	 * Setter for resource property. The location of an input stream that can be
 	 * read.
@@ -227,6 +236,9 @@ public class FlatFileItemReader<T> extends AbstractItemReaderItemStream<T> imple
 				String[] names = tokenizer.tokenize(firstLine).getValues();
 				((AbstractLineTokenizer) tokenizer).setNames(names);
 			}
+			if (headerCallback != null) {
+				headerCallback.handleLine(firstLine);
+			}
 		}
 
 	}

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

@@ -0,0 +1,12 @@
+package org.springframework.batch.item.file;
+
+/**
+ * Callback interface for handling a line from file. Useful e.g. for header
+ * processing.
+ * 
+ * @author Robert Kasanicky
+ */
+public interface LineCallbackHandler {
+
+	void handleLine(String line);
+}

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

@@ -20,6 +20,7 @@ import java.io.IOException;
 import java.io.InputStream;
 
 import junit.framework.TestCase;
+import static org.easymock.EasyMock.*;
 
 import org.springframework.batch.item.ExecutionContext;
 import org.springframework.batch.item.ItemStreamException;
@@ -228,15 +229,21 @@ public class FlatFileItemReaderBasicTests extends TestCase {
 
 	/**
 	 * Header line is skipped and used to setup fieldSet column names.
+	 * It is also passed to header callback.
 	 */
 	public void testColumnNamesInHeader() throws Exception {
 		final String INPUT = "name1|name2\nvalue1|value2\nvalue3|value4";
+		
+		LineCallbackHandler headerCallback = createStrictMock(LineCallbackHandler.class);
+		headerCallback.handleLine("name1|name2");
+		replay(headerCallback);
 
 		itemReader = new FlatFileItemReader<FieldSet>();
 		itemReader.setResource(getInputResource(INPUT));
 		itemReader.setLineTokenizer(new DelimitedLineTokenizer('|'));
 		itemReader.setFieldSetMapper(fieldSetMapper);
 		itemReader.setFirstLineIsHeader(true);
+		itemReader.setHeaderCallback(headerCallback);
 		itemReader.afterPropertiesSet();
 		itemReader.open(executionContext);
 
@@ -247,6 +254,8 @@ public class FlatFileItemReaderBasicTests extends TestCase {
 		fs = itemReader.read();
 		assertEquals("value3", fs.readString("name1"));
 		assertEquals("value4", fs.readString("name2"));
+		
+		verify(headerCallback);
 	}
 
 	/**