用gzip解压缩数据流

//package com.nowjava;

import java.io.BufferedInputStream;

import java.io.BufferedOutputStream;
/** 
来 自 
NowJava.com
**/

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;


import java.util.zip.GZIPInputStream;


public class Main {
/* 
 来自 
*时代Java公众号 - nowjava.com*/

    private static final int BYTE_BUFFER = 1024;

    private static final String GZIP_FILE_SUFFIX = ".gz";


    /**

     * uncompress data stream

     * @author Crow

     * @date 2015?6?19?

     * @version v0.1

     * @param is   input stream of bytes

     * @param os   output stream of bytes

     * @throws IOException

     */

    public static void ungzip(InputStream is, OutputStream os)

            throws IOException {

        GZIPInputStream gis = new GZIPInputStream(is);


        byte[] data = new byte[BYTE_BUFFER];

        int length = -1;

        while ((length = gis.read(data)) != -1) {

            os.write(data, 0, length);

        }


        gis.close();

    }


    /**

     * uncompress bytes

     * @author Crow

     * @date 2015?6?19?

     * @version v0.1

     * @param content   the bytes to be uncompressed

     * @return

     * @throws IOException

     */

    public static byte[] ungzip(byte[] content) throws IOException {

        ByteArrayInputStream bis = new ByteArrayInputStream(content);

        ByteArrayOutputStream bos = new ByteArrayOutputStream();


        ungzip(bis, bos);


        bos.flush();

        byte[] result = bos.toByteArray();

        bos.close();

        bis.close();


        return result;

    }


    public static boolean ungzip(File gzipFile) {

        return ungzip(gzipFile, true);

    }


    public static boolean ungzip(File gzipFile, boolean deleteSourceFile) {

        String fileName = gzipFile.getName();

        if (fileName.endsWith(GZIP_FILE_SUFFIX)) {

            fileName = fileName.substring(0,

                    fileName.lastIndexOf(GZIP_FILE_SUFFIX));

        } else {

            fileName = "ungz-" + fileName;

        }

        File targetFile = new File(gzipFile.getParent(), fileName);

        return ungzip(gzipFile, targetFile, deleteSourceFile);

    }


    public static boolean ungzip(File gzipFile, File targetFile,

            boolean deleteSourceFile) {

        BufferedInputStream bis = null;

        try {

            bis = new BufferedInputStream(new FileInputStream(gzipFile));

        } catch (FileNotFoundException e) {

            System.out.println("??????gz????????????????");

            e.printStackTrace();

            return false;

        }


        BufferedOutputStream bos = null;

        try {

            bos = new BufferedOutputStream(new FileOutputStream(targetFile));

        } catch (FileNotFoundException e) {

            e.printStackTrace();

            try {

                if (bis != null)

                    bis.close();

            } catch (IOException e1) {

                e1.printStackTrace();

            }

            return false;

        }


        GZIPInputStream gis = null;

        try {

            gis = new GZIPInputStream(bis);

            byte[] data = new byte[BYTE_BUFFER];

            int length = -1;

            while ((length = gis.re