Commons IO example source code file (DirectoryFileFilter.java)

This example Commons IO source code file (DirectoryFileFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons IO tags/keywords

abstractfilefilter, abstractfilefilter, directory, directory, directoryfilefilter, directoryfilefilter, instance, io, iofilefilter, iofilefilter, override, serializable

The Commons IO DirectoryFileFilter.java source code

/*
 * 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.commons.io.filefilter;

import java.io.File;
import java.io.Serializable;

/**
 * This filter accepts <code>Files that are directories.
 * <p>
 * For example, here is how to print out a list of the 
 * current directory's subdirectories:
 *
 * <pre>
 * File dir = new File(".");
 * String[] files = dir.list( DirectoryFileFilter.INSTANCE );
 * for ( int i = 0; i < files.length; i++ ) {
 *     System.out.println(files[i]);
 * }
 * </pre>
 *
 * @since Commons IO 1.0
 * @version $Revision: 1005099 $ $Date: 2010-10-06 17:13:01 +0100 (Wed, 06 Oct 2010) $
 *
 * @author Stephen Colebourne
 * @author Peter Donald
 * @see FileFilterUtils#directoryFileFilter()
 */
public class DirectoryFileFilter extends AbstractFileFilter implements Serializable {

    /**
     * Singleton instance of directory filter.
     * @since Commons IO 1.3
     */
    public static final IOFileFilter DIRECTORY = new DirectoryFileFilter();
    /**
     * Singleton instance of directory filter.
     * Please use the identical DirectoryFileFilter.DIRECTORY constant.
     * The new name is more JDK 1.5 friendly as it doesn't clash with other
     * values when using static imports.
     */
    public static final IOFileFilter INSTANCE = DIRECTORY;

    /**
     * Restrictive consructor.
     */
    protected DirectoryFileFilter() {
    }

    /**
     * Checks to see if the file is a directory.
     *
     * @param file  the File to check
     * @return true if the file is a directory
     */
    @Override
    public boolean accept(File file) {
        return file.isDirectory();
    }

}