raf.read(magicBuf);
boolean validRead = true;
  private void checkZipFile() throws IOException, ZipException  {    byte[] magicBuf = new byte[4];    raf.read(magicBuf);    if (readLeInt(magicBuf, 0) != LOCSIG)      {	raf.close();	throw new ZipException("Not a valid zip file");      }  }