ReadableByteChannelImpl(InputStream in) 
{
          
            this.in = in;
}

 protected  void implCloseChannel() throws IOException 
{
            in.close();
            open = false;
}

 public int read(ByteBuffer dst) throws IOException 
{
            int len = dst.remaining();
            int totalRead = 0;
            int bytesRead = 0;
            synchronized (readLock) {
                while (totalRead <  len) {
                    int bytesToRead = Math.min((len - totalRead),
                                               TRANSFER_SIZE);
                    if (buf.length <  bytesToRead)
                        buf = new byte[bytesToRead];
                    if ((totalRead  > 0) && !(in.available()  > 0))
                        break; // block at most once
                    try {
                        begin();
                        bytesRead = in.read(buf, 0, bytesToRead);
                    } finally {
                        end(bytesRead  > 0);
                    }
                    if (bytesRead <  0)
                        break;
                    else
                        totalRead += bytesRead;
                    dst.put(buf, 0, bytesRead);
                }
                if ((bytesRead <  0) && (totalRead == 0))
                    return -1;
                return totalRead;
            }
}