ems/boco/src/main/java/org/onap/vfc/nfvo/emsdriver/commons/utils/Gunzip.java

   1 /**
   2  * Copyright 2017 CMCC Technologies Co., Ltd
   3  * <p>
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  * <p>
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  * <p>
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.onap.vfc.nfvo.emsdriver.commons.utils;
  17
  18 import java.io.*;
  19 import java.util.zip.GZIPInputStream;
  20
  21 public class Gunzip {
  22
  23         /**
  24          *
  25          */
  26         public void unCompress(String gzFileName, String toFile) throws IOException {
  27                 try (   FileInputStream gzInput = new FileInputStream(gzFileName);
  28                         GZIPInputStream gzIn = new GZIPInputStream(gzInput)){
  29                         File tofile = new File(toFile);
  30                         enable(tofile);
  31                         try(FileOutputStream fileOutput = new FileOutputStream(tofile, false)){
  32                                 moveBytes(gzIn, fileOutput, -1, -1, 1024);
  33                         }
  34                 }catch(IOException e){
  35                 throw e;
  36                 }
  37
  38         }
  39
  40         private void enable(File tofile) throws IOException {
  41                 if (!tofile.exists()) {
  42                         String parentPath = tofile.getParent();
  43                         if (parentPath != null)
  44                                 new File(parentPath).mkdirs();
  45                         tofile.createNewFile();
  46                 }
  47         }
  48
  49         public long moveBytes(InputStream input, OutputStream output, long off, long len, int bufsize) throws IOException {
  50                 long skipped=0;
  51                 if (off > 0)
  52                         skipped = input.skip(off); // check if skipped is same as off
  53
  54                 long totalNum = 0;
  55                 byte[] buf = new byte[bufsize];
  56
  57                 while (true) {
  58                         if (len > 0 && (len - totalNum) <= 0)
  59                                 break;
  60
  61                         else if (len > 0 && bufsize > (len - totalNum))
  62                                 bufsize = (int) (len - totalNum);
  63
  64                         int readNum = input.read(buf, 0, bufsize);
  65                         if (readNum <= 0)
  66                                 break;
  67
  68                         output.write(buf, 0, readNum);
  69                         totalNum += readNum;
  70                 }
  71                 buf = null;
  72                 return totalNum;
  73         }
  74
  75 }