question: public void writeTo ( OutputStream out ) throws IOException { ByteString [ ] cachedFlushBuffers ; byte [ ] cachedBuffer ; int cachedBufferPos ; synchronized ( this ) { cachedFlushBuffers = flushedBuffers . toArray ( new ByteString [ flushedBuffers . size ( ) ] ) ; cachedBuffer = buffer ; cachedBufferPos = bufferPos ; } for ( ByteString byteString : cachedFlushBuffers ) { byteString . writeTo ( out ) ; } out . write ( copyArray ( cachedBuffer , cachedBufferPos ) ) ; }
target:  Writes the complete contents of this byte array output stream to the specified output stream argument.