code: public static void unzip(File file, File destDir) throws IOException {
          if (!destDir.exists()) {
              destDir.mkdir();
          }
          ZipInputStream zipIn = new ZipInputStream(new FileInputStream(file));
          ZipEntry entry = zipIn.getNextEntry();
          // iterates over entries in the zip file
          while (entry != null) {
              File entryFile = new File(destDir, entry.getName());
              if (!entry.isDirectory()) {
                  // if the entry is a file, extracts it
                  extractFile(zipIn, entryFile);
              } else {
                  // if the entry is a directory, make the directory
                  entryFile.mkdir();
              }
              zipIn.closeEntry();
              entry = zipIn.getNextEntry();
          }
          zipIn.close();
      }
docs: Extracts a zip file specified by the zipFilePath to a directory specified by
  destDirectory (will be created if does not exists)