public long calcDataOffset() throws IOException {
    long offset = getHeaderOffset();
    myFile.myArchive.seek(offset + JBZipFile.LFH_OFFSET_FOR_FILENAME_LENGTH);
    byte[] b = new byte[JBZipFile.WORD];
    myFile.myArchive.readFully(b);
    int fileNameLen = ZipShort.getValue(b, 0);
    int extraFieldLen = ZipShort.getValue(b, JBZipFile.SHORT);
    return offset + JBZipFile.LFH_OFFSET_FOR_FILENAME_LENGTH + JBZipFile.WORD + fileNameLen + extraFieldLen;
  }
public long calcDataOffset()