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         public void unCompress(String gzFileName, String toFile) throws IOException {
  24                 try (   FileInputStream gzInput = new FileInputStream(gzFileName);
  25                         GZIPInputStream gzIn = new GZIPInputStream(gzInput)){
  26                         File tofile = new File(toFile);
  27                         enable(tofile);
  28                         try(FileOutputStream fileOutput = new FileOutputStream(tofile, false)){
  29                                 moveBytes(gzIn, fileOutput, -1, -1, 1024);
  30                         }
  31                 }catch(IOException e){
  32                         throw new IOException ("Gunzip", e);
  33                 }
  34
  35         }
  36
  37         private void enable(File tofile) throws IOException {
  38                 if (!tofile.exists()) {
  39                         String parentPath = tofile.getParent();
  40                         if (parentPath != null)
  41                                 new File(parentPath).mkdirs();
  42                         tofile.createNewFile();
  43                 }
  44         }
  45
  46         public long moveBytes(InputStream input, OutputStream output, long off, long len, int bufsize) throws IOException {
  47                 /*      long skipped=0;
  48                         if (off > 0)
  49                         skipped = input.skip(off); // check if skipped is same as off
  50                 */
  51                 long totalNum = 0;
  52                 byte[] buf = new byte[bufsize];
  53
  54                 while (true) {
  55                         if (len > 0 && (len - totalNum) <= 0)
  56                                 break;
  57
  58                         else if (len > 0 && bufsize > (len - totalNum))
  59                                 bufsize = (int) (len - totalNum);
  60
  61                         int readNum = input.read(buf, 0, bufsize);
  62                         if (readNum <= 0)
  63                                 break;
  64
  65                         output.write(buf, 0, readNum);
  66                         totalNum += readNum;
  67                 }
  68                 return totalNum;
  69         }
  70
  71 }