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文件io Java:解压比压缩慢得多

我有一些代码,可以将一个文件通过网络发送,然后在另一端解压。我还在测试代码,源代码和目标代码是一样的。压缩文件需要一分钟的时间。解压文件需要一个小时。我觉得我的代码中一定有缺陷,才会有这么大的差异。以下是要解压缩的代码:

public String uncompressLocalZip(String filename,String strUUID,ParentEntry pe,boolean bControlFileProgress) {
        final int BUFFER = 2048;
        BufferedOutputStream out  = null;
        ZipInputStream zis = null;

        try {

            FileInputStream fis = new FileInputStream(Constants.conf.getFileDirectory() + Constants.PATH_SEPARATOR + strUUID + Constants.PATH_SEPARATOR + filename);
            zis = new  ZipInputStream(new BufferedInputStream(fis));
            ZipEntry entry;
            long totallength = 0;
            long size = 0;
            if (pe !=null)
                size = pe.getSize();


            while((entry = zis.getNextEntry()) != null) {
                System.out.println("Extracting: " +entry);
                int count;
                byte data[] = new byte[BUFFER];
                // write the files to the disk

                File fileOutput = new File(Constants.conf.getFileDirectory() + Constants.PATH_SEPARATOR + strUUID + Constants.PATH_SEPARATOR + Constants.conf.getUncompressFolderName() + Constants.PATH_SEPARATOR + entry.getName());
                new File(fileOutput.getParent()).mkdirs();


                BufferedOutputStream fos = new BufferedOutputStream(new FileOutputStream(fileOutput));

                out = new BufferedOutputStream(fos, BUFFER);
                while ((count = zis.read(data, 0, BUFFER)) != -1) {
                       out.write(data, 0, count);
                       totallength += count;

            }
            out.flush();

        }

     }
     catch(Exception e) {
        e.printStackTrace();
        return("FAILED");
     }
     finally {
        try {if ( out!= null) out.close();} catch (IOException ioe) {}
        try {if ( zis!= null) zis.close();} catch (IOException ioe) {}

     }

    return("SUCCESS");      



}

以下是邮政编码:

public void createLocalZip(String filename,ProcessEntry pe) {
    ZipOutputStream out=null;
    try {

        File fileOutput = new File (filename);
        out = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream(fileOutput)));
        long totallength=0;
        long size = pe.getParentEntry().getSize();

        String strStartDirectory;
        if (pe.getParentEntry().isDirectory())
            strStartDirectory=pe.getParentEntry().getUrl();
        else
            strStartDirectory=pe.getParentEntry().getFolder();



        for (int i=0;i<pe.getParentEntry().tableModel3.getRowCount();i++) {
            FileEntry fe = pe.getParentEntry().tableModel3.getFileEntry(i);
            File fileInput = new File (fe.getUrl());
            FileInputStream input = new FileInputStream(fileInput);
            BufferedInputStream in = new BufferedInputStream(input);

            String strRelativeDir = fe.getUrl().substring(strStartDirectory.length()+1,fe.getUrl().length());

            ZipEntry entry = new ZipEntry(strRelativeDir);

            out.putNextEntry(entry);


            byte[] bbuf = new byte[2048];
            int length=0;




             while ((in != null) && ((length = in.read(bbuf)) != -1)) {

                    out.write(bbuf,0,length);
                    totallength += length;
                    pe.setProgress((int) (totallength*100/size));

             }

             in.close();


        }






    }
    catch (Exception e) {
        System.out.println(e.getMessage());
    }
    finally {
        try {if (out!=null) out.close();} catch(IOException ioe){}
    }


}

更新:此特定测试的压缩比约为90%(1.2GB降至约100MB)。所以我想这可能是额外的磁盘写入,用于解压和压缩,尽管我预计会接近10倍于60倍


共 (0) 个答案