AbstractDirectoryListing.java

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2015 Lachlan Dowding
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package permafrost.tundra.io;

import java.io.File;
import java.util.ArrayList;
import java.util.List;

/**
 * Implements the convenience methods in DirectoryListing interface.
 */
public abstract class AbstractDirectoryListing implements DirectoryListing {
    /**
     * Returns all the files and directories in this listing.
     *
     * @return All the files and directories in this listing.
     */
    abstract public List<File> listAll();

    /**
     * Returns all the files and directories in this listing as a String[].
     *
     * @return All the files and directories in this listing as a String[].
     */
    public String[] listAllAsStringArray() {
        return (convertListToStringArray(listAll()));
    }

    /**
     * Returns all the directories in this listing.
     *
     * @return All the directories in this listing.
     */
    abstract public List<File> listDirectories();

    /**
     * Returns all the directories in this listing as a String[].
     *
     * @return All the directories in this listing as a String[].
     */
    public String[] listDirectoriesAsStringArray() {
        return (convertListToStringArray(listDirectories()));
    }

    /**
     * Returns all the files in this listing.
     *
     * @return All the files in this listing.
     */
    abstract public List<File> listFiles();

    /**
     * Returns all the files in this listing as a String[].
     *
     * @return All the files in this listing as a String[].
     */
    public String[] listFilesAsStringArray() {
        return (convertListToStringArray(listFiles()));
    }

    /**
     * Returns the directory which produced this listing.
     *
     * @return The directory which produced this listing.
     */
    abstract public File getDirectory();

    /**
     * Returns the directory which produced this listing as a String.
     *
     * @return The directory which produced this listing as a String.
     */
    public String getDirectoryAsString() {
        return FileHelper.normalize(getDirectory());
    }

    /**
     * Converts a List to a String[].
     *
     * @param list  The List to be converted.
     * @return      The String[] representation of the given list.
     */
    private String[] convertListToStringArray(List<File> list) {
        if (list == null) return null;

        List<String> output = new ArrayList<String>(list.size());

        for (File file : list) {
            output.add(FileHelper.normalize(file));
        }

        return output.toArray(new String[output.size()]);
    }
}