convenience additions + Resources.toString()

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@290809 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/types/resources/Resources.java

@@ -17,6 +17,7 @@
 
 package org.apache.tools.ant.types.resources;
 
+import java.io.File;
 import java.util.Stack;
 import java.util.Vector;
 import java.util.Iterator;
@@ -35,6 +36,28 @@ import org.apache.tools.ant.types.ResourceCollection;
  * @since Ant 1.7
  */
 public class Resources extends DataType implements ResourceCollection {
+    /** static empty ResourceCollection */
+    public static final ResourceCollection NONE = new ResourceCollection() {
+        public boolean isFilesystemOnly() {
+            return true;
+        }
+        public Iterator iterator() {
+            return new Iterator() {
+                public Object next() {
+                    throw new NoSuchElementException();
+                }
+                public boolean hasNext() {
+                    return false;
+                }
+                public void remove() {
+                    throw new UnsupportedOperationException();
+                }
+            };
+        }
+        public int size() {
+            return 0;
+        }
+    };
 
     private class MyCollection extends AbstractCollection {
         int size;
@@ -183,4 +206,25 @@ public class Resources extends DataType implements ResourceCollection {
         coll = (coll == null) ? new MyCollection() : coll;
     }
 
+    /**
+     * Format this BaseResourceCollectionContainer as a String.
+     * @return a descriptive <code>String</code>.
+     */
+    public synchronized String toString() {
+        if (isReference()) {
+            return getCheckedRef().toString();
+        }
+        if (coll.size() == 0) {
+            return "";
+        }
+        StringBuffer sb = new StringBuffer();
+        for (Iterator i = coll.iterator(); i.hasNext();) {
+            if (sb.length() > 0) {
+                sb.append(File.pathSeparatorChar);
+            }
+            sb.append(i.next());
+        }
+        return sb.toString();
+    }
+
 }

src/main/org/apache/tools/ant/types/resources/Union.java

@@ -22,6 +22,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 
+import org.apache.tools.ant.types.Resource;
 import org.apache.tools.ant.types.ResourceCollection;
 
 /**
@@ -30,6 +31,29 @@ import org.apache.tools.ant.types.ResourceCollection;
  */
 public class Union extends BaseResourceCollectionContainer {
 
+    /**
+     * Static convenience method to union an arbitrary set of Resources.
+     * @param rc a ResourceCollection.
+     * @return a Union.
+     */
+    public static Union getInstance(ResourceCollection rc) {
+        return rc instanceof Union ? (Union) rc : new Union(rc);
+    }
+
+    /**
+     * Default constructor.
+     */
+    public Union() {
+    }
+
+    /**
+     * Convenience constructor.
+     * @param rc the ResourceCollection to add.
+     */
+    public Union(ResourceCollection rc) {
+        add(rc);
+    }
+
     /**
      * Returns all Resources in String format. Moved up from
      * Path for convenience.
@@ -43,6 +67,18 @@ public class Union extends BaseResourceCollectionContainer {
         return (String[]) (result.toArray(new String[result.size()]));
     }
 
+    /**
+     * Convenience method.
+     * @return Resource[]
+     */
+    public Resource[] listResources() {
+        if (isReference()) {
+            return ((Union) getCheckedRef()).listResources();
+        }
+        Collection result = getCollection();
+        return (Resource[]) (result.toArray(new Resource[result.size()]));
+    }
+
     /**
      * Unify the contained Resources.
      * @return a Collection of Resources.