Make a SimpleJobIdentifierFactory for SimpleJobIdentifiers

OPEN - issue BATCH-58: Make JobStream and JobRun optional properties of Job (e.g. through join to optional table) 
http://opensource.atlassian.com/projects/spring/browse/BATCH-58

core/src/main/java/org/springframework/batch/core/runtime/JobIdentifier.java

@@ -16,9 +16,25 @@
 
 package org.springframework.batch.core.runtime;
 
+import org.springframework.batch.core.domain.JobInstance;
 
+/**
+ * Identifier strategy for {@link JobInstance}. Different batch projects can
+ * have different approaches and requirements regarding the identity of a job.
+ * The minimum requirement is to provide a unique name to identify a job. Other
+ * applications or projects might add other properties like a schedule date, or
+ * an additional label (code).
+ * 
+ * @author Dave Syer
+ * 
+ */
 public interface JobIdentifier {
-	
+
+	/**
+	 * A name property for jobs provided by the {@link JobIdentifier} strategy.
+	 * 
+	 * @return the name of the job
+	 */
 	public String getName();
 
 }

core/src/main/java/org/springframework/batch/core/runtime/SimpleJobIdentifierFactory.java

@@ -0,0 +1,24 @@
+package org.springframework.batch.core.runtime;
+
+
+/**
+ * Factory for {@link SimpleJobIdentifier} instances.
+ * 
+ * @author Dave Syer
+ *
+ */
+public class SimpleJobIdentifierFactory implements JobIdentifierFactory {
+
+	/**
+	 * Create a {@link JobIdentifier} with the given name.
+	 * 
+	 * @param name the name for the {@link JobIdentifier}
+	 * @return a {@link JobIdentifier} with the given name.
+	 * 
+	 * @see org.springframework.batch.core.runtime.JobIdentifierFactory#getJobIdentifier(java.lang.String)
+	 */
+	public JobIdentifier getJobIdentifier(String name) {
+		return new SimpleJobIdentifier(name);
+	}
+
+}

core/src/test/java/org/springframework/batch/core/runtime/SimpleJobIdentifierFactoryTests.java

@@ -0,0 +1,12 @@
+package org.springframework.batch.core.runtime;
+
+import junit.framework.TestCase;
+
+public class SimpleJobIdentifierFactoryTests extends TestCase {
+
+	public void testGetJobIdentifier() {
+		JobIdentifier jobIdentifier = new SimpleJobIdentifierFactory().getJobIdentifier("foo");
+		assertEquals("foo", jobIdentifier.getName());
+	}
+
+}