Dust off JMX demo

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

@@ -71,6 +71,13 @@ public class DefaultFieldSet implements FieldSet {
 		}
 		return (String[]) names.toArray();
 	}
+	
+	/* (non-Javadoc)
+	 * @see org.springframework.batch.item.file.mapping.FieldSet#hasNames()
+	 */
+	public boolean hasNames() {
+		return names!=null;
+	}
 
 	/*
 	 * (non-Javadoc)

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

@@ -40,6 +40,13 @@ public interface FieldSet {
 	 */
 	String[] getNames();
 
+	/**
+	 * Check if there are names defined for the fields.
+	 * 
+	 * @return true if there are names for the fields
+	 */
+	boolean hasNames();
+
 	/**
 	 * @return fields wrapped by this '<code>FieldSet</code>' instance as
 	 * String values.

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

@@ -45,11 +45,13 @@ public class FieldSetTests extends TestCase {
 	}
 
 	public void testNames() throws Exception {
+		assertTrue(fieldSet.hasNames());
 		assertEquals(fieldSet.getFieldCount(), fieldSet.getNames().length);
 	}
 
 	public void testNamesNotKnown() throws Exception {
 		fieldSet = new DefaultFieldSet(new String[] { "foo" });
+		assertFalse(fieldSet.hasNames());
 		try {
 			fieldSet.getNames();
 			fail("Expected IllegalStateException");