Java ZipFile Read copyFileFromZip(File zipResource, String jarFileNAme, File destFile)

Description

Copies jar file from zip

License

Apache License

Exception

Parameter	Description
IOException	an exception

Declaration

public static boolean copyFileFromZip(File zipResource, String jarFileNAme, File destFile) throws IOException 

Method Source Code

//package com.java2s;
/**/*from w  w  w. j a  v  a 2 s  .com*/
 * Copyright 2013 Microsoft Open Technologies Inc.
 *
 * 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.BufferedOutputStream;
import java.io.File;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

public class Main {
    private static final int BUFF_SIZE = 1024;

    /**
     * Copies jar file from zip 
     * @throws IOException 
     */
    public static boolean copyFileFromZip(File zipResource, String jarFileNAme, File destFile) throws IOException {

        boolean jarCopied = false;

        ZipFile zipFile = new ZipFile(zipResource);
        Enumeration<? extends ZipEntry> entries = zipFile.entries();

        while (entries.hasMoreElements()) {
            ZipEntry zipEntry = (ZipEntry) entries.nextElement();
            if (zipEntry.getName().equals(jarFileNAme)) {
                writeFile(zipFile.getInputStream(zipEntry),
                        new BufferedOutputStream(new FileOutputStream(destFile)));
                jarCopied = true;
            }
        }
        zipFile.close();

        return jarCopied;

    }

    /**
     * Method writes contents of file.
     * @param inStream
     * @param outStream
     * @throws IOException
     */
    public static void writeFile(InputStream inStream, OutputStream outStream) throws IOException {

        try {
            byte[] buf = new byte[BUFF_SIZE];
            int len = inStream.read(buf);
            while (len > 0) {
                outStream.write(buf, 0, len);
                len = inStream.read(buf);
            }
        } finally {
            if (inStream != null) {
                inStream.close();
            }
            if (outStream != null) {
                outStream.close();
            }
        }
    }
}