/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */
package org.apache.tools.ant.types;

import java.util.Iterator;

/**
 * Interface describing a collection of Resources.
 * @since Ant 1.7
 */
public interface ResourceCollection extends Iterable<Resource> {

    /**
     * Gets the contents of this collection.
     * @return all resources in the collection
     */
    Iterator<Resource> iterator();

    /**
     * Learn the number of contained Resources.
     * @return number of elements as int.
     */
    int size();

    /**
     * Indicate whether this ResourceCollection is composed entirely of
     * Resources accessible via local filesystem conventions. If true,
     * all resources returned from this collection should
     * respond with a {@link org.apache.tools.ant.types.resources.FileProvider}
     * when asked via {@link Resource#as}.
     * @return whether this is a filesystem-only resource collection.
     */
    boolean isFilesystemOnly();

}