Netty Bytetomessagedecoder Analysis

Bytetomessagedecoder1trigger on socket removal, last read data processing @Override Public Final voidHandlerremoved (Channelhandlercontext ctx)throwsException {bytebuf buf=Internalbuffer (); if(Buf.isreadable ()) {bytebuf bytes=buf.readbytes (Buf.readablebytes ());                Buf.release ();            Ctx.firechannelread (bytes); } cumulation=NULL;            Ctx.firechannelreadcomplete ();        HandlerRemoved0 (CTX); }                2read the data bytebuf Release,discardsomereadbytes method after the study Public voidChannelread (Channelhandlercontext ctx, Object msg)throwsException {recyclablearraylist out= Recyclablearraylist.newinstance ();//creating an array that has been wrapped            Try {                if(msginstanceofbytebuf) {BYTEBUF Data=(BYTEBUF) msg; if(cumulation = =NULL) {//whether to continue reading datacumulation =data; Try{Calldecode (CTX, cumulation, out); } finally {                            if(cumulation! =NULL&&!cumulation.isreadable ())                                {cumulation.release (); Cumulation=NULL; }                        }                    } Else{//continue read processing                        Try {                            //Create a new space if there is not enough space left to open                            if(Cumulation.writerindex () > Cumulation.maxcapacity ()-data.readablebytes ()) {Bytebuf oldcumulation=cumulation; Cumulation= Ctx.alloc (). Buffer (Oldcumulation.readablebytes () +data.readablebytes ());                                Cumulation.writebytes (oldcumulation);                            Oldcumulation.release ();                            } cumulation.writebytes (data);                        Calldecode (CTX, cumulation, out); } finally {                            if(cumulation! =NULL) {                                if(!cumulation.isreadable ())                                    {cumulation.release (); Cumulation=NULL; } Else{cumulation.discardsomereadbytes ();                        }} data.release (); }                    }                } Else{out.add (msg); }            } Catch(decoderexception e) {Throwe; } Catch(Throwable t) {Throw Newdecoderexception (t); } finally {                intSize =out.size (); if(Size = = 0) {Decodewasnull=true; } Else {                     for(inti = 0; i < size; i + +) {Ctx.firechannelread (Out.get (i));            }} out.recycle (); }        }                //In fact, as long as the core code decode call business processing         protected voidCalldecode (Channelhandlercontext ctx, bytebuf in, list<object>Out ) {            Try {                //Looping through data                 while(In.isreadable ()) {intoutsize =out.size (); intOldinputlength =in.readablebytes (); Decode (CTX, in, out);//Business Expansion Processing//Check If this handler is removed before continuing the loop. //If It was removed, it's not safe for continue to operate on the buffer. //                    // Seehttps://github.com/netty/netty/issues/1664                    //If handler is deleted, then the data is not read                    if(ctx.isremoved ()) { Break; }                    //The following is not clearly written .....                                         if(Outsize = =out.size ()) {                        if(Oldinputlength = =in.readablebytes ()) {                             Break; } Else {                            Continue; }                    }                    if(Oldinputlength = =in.readablebytes ()) {                        Throw Newdecoderexception (Stringutil.simpleclassname (GetClass ())+ ". Decode () did not read anything but decoded a message."); }                    if(Issingledecode ()) { Break; }                }            } Catch(decoderexception e) {Throwe; } Catch(Throwable cause) {Throw Newdecoderexception (cause); }        }

Netty Bytetomessagedecoder Analysis