Package org.bluezoo.gumdrop.mqtt.codec

Class MQTTPacketEncoder

java.lang.Object

org.bluezoo.gumdrop.mqtt.codec.MQTTPacketEncoder

public final class MQTTPacketEncoder
extends Object

Encodes MQTT control packets to wire format.

Each encode* method returns a ByteBuffer in read mode containing the complete packet ready for transmission.

All methods use flat parameter signatures — no packet objects are required except for encodeConnect(ConnectPacket) which retains the packet object due to its 12+ fields.

Author:

Chris Burdess

Method Summary

Modifier and Type	Method	Description
static ByteBuffer	encodeAuth(int reasonCode, MQTTProperties props)
static ByteBuffer	encodeConnAck(boolean sessionPresent, int returnCode, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodeConnect(ConnectPacket packet)
static ByteBuffer	encodeDisconnect(int reasonCode, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodePingReq()
static ByteBuffer	encodePingResp()
static ByteBuffer	encodePubAck(int packetId, int reasonCode, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodePubComp(int packetId, int reasonCode, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodePublish(String topic, int qos, boolean dup, boolean retain, int packetId, byte[] payload, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodePublishHeader(String topic, int qos, boolean dup, boolean retain, int packetId, long payloadSize, MQTTProperties props, MQTTVersion version)	Encodes just the PUBLISH fixed header and variable header, without the payload.
static ByteBuffer	encodePubRec(int packetId, int reasonCode, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodePubRel(int packetId, int reasonCode, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodeSubAck(int packetId, int[] returnCodes, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodeSubscribe(int packetId, String[] topicFilters, int[] qosLevels, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodeUnsubAck(int packetId, int[] reasonCodes, MQTTProperties props, MQTTVersion version)
static ByteBuffer	encodeUnsubscribe(int packetId, String[] topicFilters, MQTTProperties props, MQTTVersion version)

Methods inherited from class java.lang.Object

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

Method Details

encodeConnect

public static ByteBuffer encodeConnect(ConnectPacket packet)

encodeConnAck

public static ByteBuffer encodeConnAck(boolean sessionPresent,
 int returnCode,
 MQTTProperties props,
 MQTTVersion version)

encodePublish

public static ByteBuffer encodePublish(String topic,
 int qos,
 boolean dup,
 boolean retain,
 int packetId,
 byte[] payload,
 MQTTProperties props,
 MQTTVersion version)

encodePublishHeader

public static ByteBuffer encodePublishHeader(String topic,
 int qos,
 boolean dup,
 boolean retain,
 int packetId,
 long payloadSize,
 MQTTProperties props,
 MQTTVersion version)

Encodes just the PUBLISH fixed header and variable header, without the payload. Used for streaming delivery where the payload is sent separately via chunked Endpoint.send(java.nio.ByteBuffer) calls from an ReadableByteChannel.

The remaining length in the fixed header includes the payload size, so the receiver can determine the frame boundary.

Parameters:

topic - the topic name

qos - the QoS level (0, 1, or 2)

dup - the DUP flag

retain - the RETAIN flag

packetId - the packet identifier (0 for QoS 0)

payloadSize - the payload size in bytes

props - MQTT 5.0 properties

version - the MQTT version

Returns:

a ByteBuffer containing the fixed + variable header

encodePubAck

public static ByteBuffer encodePubAck(int packetId,
 int reasonCode,
 MQTTProperties props,
 MQTTVersion version)

encodePubRec

public static ByteBuffer encodePubRec(int packetId,
 int reasonCode,
 MQTTProperties props,
 MQTTVersion version)

encodePubRel

public static ByteBuffer encodePubRel(int packetId,
 int reasonCode,
 MQTTProperties props,
 MQTTVersion version)

encodePubComp

public static ByteBuffer encodePubComp(int packetId,
 int reasonCode,
 MQTTProperties props,
 MQTTVersion version)

encodeSubscribe

public static ByteBuffer encodeSubscribe(int packetId,
 String[] topicFilters,
 int[] qosLevels,
 MQTTProperties props,
 MQTTVersion version)

encodeSubAck

public static ByteBuffer encodeSubAck(int packetId,
 int[] returnCodes,
 MQTTProperties props,
 MQTTVersion version)

encodeUnsubscribe

public static ByteBuffer encodeUnsubscribe(int packetId,
 String[] topicFilters,
 MQTTProperties props,
 MQTTVersion version)

encodeUnsubAck

public static ByteBuffer encodeUnsubAck(int packetId,
 int[] reasonCodes,
 MQTTProperties props,
 MQTTVersion version)

encodePingReq

public static ByteBuffer encodePingReq()

encodePingResp

public static ByteBuffer encodePingResp()

encodeDisconnect

public static ByteBuffer encodeDisconnect(int reasonCode,
 MQTTProperties props,
 MQTTVersion version)

encodeAuth

public static ByteBuffer encodeAuth(int reasonCode,
 MQTTProperties props)