de.uzk.hki.da.utils.FolderUtils.java Source code

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Here is the source code for de.uzk.hki.da.utils.FolderUtils.java

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/*
 DA-NRW Software Suite | ContentBroker
 Copyright (C) 2013 Historisch-Kulturwissenschaftliche Informationsverarbeitung
 Universitt zu Kln
    
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.
    
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
    
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package de.uzk.hki.da.utils;

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

import org.apache.commons.io.FileUtils;

/**
 * List folder contents.
 *
 * @param folder
 *            the folder
 * @return the list
 * @author Thomas Kleinke
 */

public class FolderUtils {
    public static final long TIME_TO_END_FILE_OPERATION = 5000;

    public static List<String> listFolderContents(File folder) {
        String[] fileNames = folder.list();

        List<String> fileList = new ArrayList<String>();

        for (String fileName : fileNames) {
            if (new File(folder.getAbsolutePath() + "/" + fileName).isDirectory()) {
                List<String> folderFileNames = listFolderContents(
                        new File(folder.getAbsoluteFile() + "/" + fileName));
                for (String folderFileName : folderFileNames)
                    fileList.add(fileName + "/" + folderFileName);
            } else
                fileList.add(fileName);
        }

        return fileList;
    }

    /**
     * Compares two folders for equality. Compares the folderstructure and the
     * compares the bitwise equality of the included files.
     *
     * @param lhs
     *            relative path to the first folder
     * @param rhs
     *            relative path to the second folder
     * @return true if lhs equals rhs
     * @throws IOException
     *             Signals that an I/O exception has occurred.
     */
    public static boolean compareFolders(File lhs, File rhs) throws IOException {

        String rhsParentPath = rhs.getAbsolutePath();
        String lhsParentPath = lhs.getAbsolutePath();

        String lhsChildren[] = lhs.list();
        String rhsChildren[] = rhs.list();

        // Sometimes the order of the listings are not equal even though the
        // files contained are
        Arrays.sort(lhsChildren);
        Arrays.sort(rhsChildren);

        boolean filesAreEqual = true;
        for (int i = 0; i < lhsChildren.length; i++) {

            File lhsf = new File(lhsParentPath + "/" + lhsChildren[i]);
            File rhsf = new File(rhsParentPath + "/" + rhsChildren[i]);

            if (lhsf.isFile()) {

                if (!FileUtils.contentEquals(lhsf, rhsf))
                    filesAreEqual = false;
            }

            if (lhsf.isDirectory()) {
                if (!compareFolders(lhsf, rhsf))
                    filesAreEqual = false;
            }
        }
        return filesAreEqual;
    }

    /**
     * Method for execute NFS-aware Directory deletion.
     * 
     * @param directory
     * @throws IOException
     */
    public static void deleteDirectorySafe(File directory) throws IOException {
        boolean successful = false;
        for (int i = 1; i < 15 & !successful; i++) {
            successful = true;
            try {
                FileUtils.deleteDirectory(directory);
            } catch (IOException e) {
                successful = false;
                System.out.println("FolderUtils::deleteDirectorySafe(): delete " + directory + " fails: " + i
                        + " x " + TIME_TO_END_FILE_OPERATION);
                waitToCompleteNFSAwareFileOperation();
                // Zweiter versuch nach einer Pause
                // FileUtils.deleteDirectory(directory);
                if (i == 14) {
                    throw e;
                }
            }
        }

    }

    public static boolean deleteQuietlySafe(File file) {
        boolean result = FileUtils.deleteQuietly(file);
        if (!result) {
            waitToCompleteNFSAwareFileOperation();
            result = FileUtils.deleteQuietly(file);
        }
        return result;
    }

    public static void waitToCompleteNFSAwareFileOperation() {
        try {
            Thread.sleep(TIME_TO_END_FILE_OPERATION);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}