Extract constant

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@272253 13f79535-47bb-0310-9956-ffa450edef68

proposal/myrmidon/src/java/org/apache/antlib/extensions/JarLibManifestTask.java

@@ -52,6 +52,11 @@ public final class JarLibManifestTask
      */
     private static final String MANIFEST_VERSION = "1.0";
 
+    /**
+     * "Created-By" string used when creating manifest.
+     */
+    private static final String CREATED_BY = "Created-By";
+
     /**
      * The library to display information about.
      */
@@ -180,7 +185,7 @@ public final class JarLibManifestTask
         final Attributes attributes = manifest.getMainAttributes();
 
         attributes.put( Attributes.Name.MANIFEST_VERSION, MANIFEST_VERSION );
-        attributes.putValue( "Created-By", Constants.BUILD_DESCRIPTION );
+        attributes.putValue( CREATED_BY, Constants.BUILD_DESCRIPTION );
 
         appendExtraAttributes( attributes );