public void processBytes(byte[] in,int inOff,int len){
  if (len == 0) {
    return;
  }
  if (len < 0) {
    throw new IllegalArgumentException("Can't have a negative input length!");
  }
  if (bufOff + len > buf.length) {
    throw new DataLengthException("attempt to process message too long for cipher");
  }
  System.arraycopy(in,inOff,buf,bufOff,len);
  bufOff+=len;
}

public void processBytes ( byte [ ] in , int inOff , int len ) { if ( len == 0 ) { return ; } if ( len < 0 ) { throw new IllegalArgumentException ( "Can't have a negative input length!" ) ; } if ( bufOff + len > buf . length ) { throw new DataLengthException ( "attempt to process message too long for cipher" ) ; } System . arraycopy ( in , inOff , buf , bufOff , len ) ; bufOff += len ; }
add len bytes to the buffer for processing .
