com.hs.mail.util.FileUtils.java Source code

Introduction

Here is the source code for com.hs.mail.util.FileUtils.java

Source

/*
 * Copyright 2010 the original author or authors.
 * 
 *  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.
 */
package com.hs.mail.util;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.builder.EqualsBuilder;

/**
 * 
 * @author Won Chul Doh
 * @since Sep 27, 2010
 *
 */
public class FileUtils {

    public final static byte[] GZIP_MAGIC_BYTES = new byte[] { (byte) 0x1F, (byte) 0x8B };

    public final static String GZIP_EXTENSION = "zip";

    public static boolean startsWith(File file, byte[] magic) {
        InputStream input = null;
        try {
            int magicLen = magic.length;
            byte[] bytes = new byte[magicLen];
            input = new FileInputStream(file);
            input.read(bytes, 0, magicLen);
            return new EqualsBuilder().append(magic, bytes).isEquals();
        } catch (IOException e) {
            return false;
        } finally {
            IOUtils.closeQuietly(input);
        }
    }

    public static boolean isCompressed(File file, boolean checkMagic) {
        return (checkMagic) ? startsWith(file, GZIP_MAGIC_BYTES)
                : GZIP_EXTENSION.equalsIgnoreCase(FilenameUtils.getExtension(file.getName()));
    }

    public static boolean createNewFile(File file) {
        try {
            return file.createNewFile();
        } catch (IOException e) {
            return false;
        }
    }

    public static void compress(File srcFile, File destFile) throws IOException {
        InputStream input = null;
        OutputStream output = null;
        try {
            input = new BufferedInputStream(new FileInputStream(srcFile));
            output = new GZIPOutputStream(new FileOutputStream(destFile));
            IOUtils.copyLarge(input, output);
        } finally {
            IOUtils.closeQuietly(output);
            IOUtils.closeQuietly(input);
        }
    }

    public static void uncompress(File srcFile, File destFile) throws IOException {
        InputStream input = null;
        OutputStream output = null;
        try {
            input = new GZIPInputStream(new FileInputStream(srcFile));
            output = new BufferedOutputStream(new FileOutputStream(destFile));
            IOUtils.copyLarge(input, output);
        } finally {
            IOUtils.closeQuietly(output);
            IOUtils.closeQuietly(input);
        }
    }

    public static void main(String[] args) throws Exception {
        if (args.length != 3) {
            System.exit(0);
        } else if ("-d".equals(args[0])) {
            uncompress(new File(args[1]), new File(args[2]));
        } else if ("-c".equals(args[0])) {
            compress(new File(args[1]), new File(args[2]));
        } else {
            System.exit(0);
        }
    }

}