Java Force Delete on Exit forceDeleteOnExit(File file)

Description

force Delete On Exit

License

Apache License

Declaration

public static void forceDeleteOnExit(File file) throws IOException 

Method Source Code

//package com.java2s;
/*/*w  w  w  .  j  av a  2  s .  c  o  m*/
 * Copyright 2015-2017 GenerallyCloud.com
 *  
 * Licensed 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.
 */

import java.io.File;

import java.io.IOException;

public class Main {
    private static final char SYSTEM_SEPARATOR = File.separatorChar;

    public static void forceDeleteOnExit(File file) throws IOException {
        if (file.isDirectory()) {
            deleteDirectoryOnExit(file);
        } else {
            file.deleteOnExit();
        }
    }

    private static void deleteDirectoryOnExit(File directory) throws IOException {
        if (!directory.exists()) {
            return;
        }
        directory.deleteOnExit();
        if (!isSymlink(directory)) {
            cleanDirectoryOnExit(directory);
        }
    }

    public static boolean isSymlink(File file) throws IOException {
        if (file == null) {
            throw new NullPointerException("File must not be null");
        }
        if (isSystemWindows()) {
            return false;
        }
        File fileInCanonicalDir = null;
        if (file.getParent() == null) {
            fileInCanonicalDir = file;
        } else {
            File canonicalDir = file.getParentFile().getCanonicalFile();
            fileInCanonicalDir = new File(canonicalDir, file.getName());
        }
        if (fileInCanonicalDir.getCanonicalFile().equals(fileInCanonicalDir.getAbsoluteFile())) {
            return false;
        }
        return true;
    }

    private static void cleanDirectoryOnExit(File directory) throws IOException {
        if (!directory.exists()) {
            String message = directory + " does not exist";
            throw new IllegalArgumentException(message);
        }
        if (!directory.isDirectory()) {
            String message = directory + " is not a directory";
            throw new IllegalArgumentException(message);
        }
        File[] files = directory.listFiles();
        if (files == null) {
            throw new IOException("Failed to list contents of " + directory);
        }
        IOException exception = null;
        for (File file : files) {
            try {
                forceDeleteOnExit(file);
            } catch (IOException ioe) {
                exception = ioe;
            }
        }
        if (null != exception) {
            throw exception;
        }
    }

    private static boolean isSystemWindows() {
        return SYSTEM_SEPARATOR == '\\';
    }
}

Related

1. forceDeleteOnExit(File file)
2. forceDeleteOnExit(File file)