压缩与解压缩类二

    /**
     * 取压缩目录内文件逐一进行压缩
     * @param baseDir 需压缩目录根路径
     * @param currentZipDir 需压缩目录中的目录
     * @param zos 写入压缩文件的输出流
     */
    private static void writeZip(String baseDir, String currentZipDir,
            ZipOutputStream zos)
    {
        File curFile = new File(currentZipDir);
        File[] fileList = curFile.listFiles();
        try
        {
            for (int i = 0; i < fileList.length; i++)
            {
                File zipfile = fileList[i];
               
                // 取得相对路径
                String relativePath = getRelativePath(baseDir, zipfile);
                ZipEntry zentry = new ZipEntry(relativePath);
                zentry.setSize(zipfile.length());
                zentry.setTime(zipfile.lastModified());
                // System.out.print("ziping: " + relativePath);
                // 将ZipEntry加到zos中，再写入实际的文件内容
                zos.putNextEntry(zentry);
               
                if (zipfile.isDirectory())
                {
                    // 如果是目录，则继续递归压缩
                    writeZip(baseDir, zipfile.getCanonicalPath(), zos);
                }
                else
                {
                    // 如果是文件，则写入其内容
                    InputStream is = new BufferedInputStream(
                            new FileInputStream(zipfile));
                    writeFile(is, zos);
                    is.close();
                }
            }
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
    }
   
    /**
     * 从输入流读入的内容写入输出流
     * @param in 输入流
     * @param out 输出流
     * @throws IOException IO异常
     */
    public static void writeFile(final InputStream in, final OutputStream out)
            throws IOException
    {
        final int diskCacheSize = 1024 * 4;
        // 4K容量的数据缓冲区，因为硬盘存取是以4K一簇为单位的
        final byte[] buffer = new byte[diskCacheSize];
       
        // 开始复制数据
        int readLen = 0;
        while ((readLen = in.read(buffer)) > 0)
        {
            out.write(buffer, 0, readLen);
        }
    }