question: public byte [ ] readRawBytes ( final int size ) throws IOException { if ( size < 0 ) { throw InvalidProtocolBufferNanoException . negativeSize ( ) ; } if ( bufferPos + size > currentLimit ) { skipRawBytes ( currentLimit - bufferPos ) ; throw InvalidProtocolBufferNanoException . truncatedMessage ( ) ; } if ( size <= bufferSize - bufferPos ) { final byte [ ] bytes = new byte [ size ] ; System . arraycopy ( buffer , bufferPos , bytes , 0 , size ) ; bufferPos += size ; return bytes ; } else { throw InvalidProtocolBufferNanoException . truncatedMessage ( ) ; } }
target:  Read a fixed size of bytes from the input.