Class MqttDecoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.ByteToMessageDecoder

io.netty.handler.codec.ReplayingDecoder<io.netty.handler.codec.mqtt.MqttDecoder.DecoderState>

io.netty.handler.codec.mqtt.MqttDecoder

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler

public final class MqttDecoder
extends ReplayingDecoder<io.netty.handler.codec.mqtt.MqttDecoder.DecoderState>

Decodes Mqtt messages from bytes, following the MQTT protocol specification v3.1 or v5.0, depending on the version specified in the CONNECT message that first goes through the channel.

Nested Class Summary

Nested classes/interfaces inherited from class ByteToMessageDecoder

ByteToMessageDecoder.Cumulator

Nested classes/interfaces inherited from interface ChannelHandler

ChannelHandler.Sharable

Field Summary

Fields inherited from class ByteToMessageDecoder

COMPOSITE_CUMULATOR, MERGE_CUMULATOR

Constructor Summary

Constructors

Constructor	Description
MqttDecoder()
MqttDecoder(int maxBytesInMessage)
MqttDecoder(int maxBytesInMessage, int maxClientIdLength)
MqttDecoder(int maxBytesInMessage, int maxClientIdLength, boolean strictUtf8Validation)	Creates a new MqttDecoder.

Method Summary

Modifier and Type	Method	Description
protected void	decode(ChannelHandlerContext ctx, ByteBuf buffer, List<Object> out)	Decode the from one ByteBuf to an other.

Methods inherited from class ReplayingDecoder

callDecode, checkpoint, checkpoint, state, state

Methods inherited from class ByteToMessageDecoder

actualReadableBytes, channelInactive, channelRead, channelReadComplete, decodeLast, discardSomeReadBytes, handlerRemoved, handlerRemoved0, internalBuffer, isSingleDecode, setCumulator, setDiscardAfterReads, setSingleDecode, userEventTriggered

Methods inherited from class ChannelInboundHandlerAdapter

channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

Methods inherited from class ChannelHandlerAdapter

ensureNotSharable, handlerAdded, isSharable

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface ChannelHandler

handlerAdded

Constructor Details

MqttDecoder

public MqttDecoder()

MqttDecoder

public MqttDecoder(int maxBytesInMessage)

MqttDecoder

public MqttDecoder(int maxBytesInMessage,
 int maxClientIdLength)

MqttDecoder

public MqttDecoder(int maxBytesInMessage,
 int maxClientIdLength,
 boolean strictUtf8Validation)

Creates a new MqttDecoder.

Parameters:

maxBytesInMessage - the maximum number of bytes a decoded message may consume.

maxClientIdLength - the maximum length of the Client Identifier (CONNECT payload).

strictUtf8Validation - if true (default), every UTF-8 Encoded String is validated according to MQTT 3.1.1 and MQTT 5.0 malformed UTF-8 sequences (including surrogates and overlong forms) and an embedded U+0000 are rejected as a Malformed Packet. If false, the legacy behaviour is preserved, malformed bytes are silently replaced with U+FFFD and U+0000 is accepted.

Method Details

decode

protected void decode(ChannelHandlerContext ctx,
 ByteBuf buffer,
 List<Object> out)
               throws Exception

Description copied from class: ByteToMessageDecoder

Decode the from one ByteBuf to an other. This method will be called till either the input ByteBuf has nothing to read when return from this method or till nothing was read from the input ByteBuf.

Specified by:

decode in class ByteToMessageDecoder

Parameters:

ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to

buffer - the ByteBuf from which to read data

out - the List to which decoded messages should be added

Throws:

Exception - is thrown if an error occurs