net.dreamlu.iot.mqtt.codec.MqttFixedHeader Maven / Gradle / Ivy
/*
* Copyright 2014 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package net.dreamlu.iot.mqtt.codec;
import java.util.Objects;
/**
* See
* MQTTV3.1/fixed-header
*
* @author netty、L.cm
*/
public final class MqttFixedHeader {
private final MqttMessageType messageType;
private final boolean isDup;
private MqttQoS qosLevel;
private final boolean isRetain;
private final int headLength;
private final int remainingLength;
public MqttFixedHeader(
MqttMessageType messageType,
boolean isDup,
MqttQoS qosLevel,
boolean isRetain,
int remainingLength) {
this(messageType, isDup, qosLevel, isRetain, 0, remainingLength);
}
public MqttFixedHeader(
MqttMessageType messageType,
boolean isDup,
MqttQoS qosLevel,
boolean isRetain,
int headLength,
int remainingLength) {
this.messageType = Objects.requireNonNull(messageType, "messageType is null.");
this.isDup = isDup;
this.qosLevel = Objects.requireNonNull(qosLevel, "qosLevel is null.");
this.isRetain = isRetain;
this.headLength = headLength;
this.remainingLength = remainingLength;
}
public MqttMessageType messageType() {
return messageType;
}
public boolean isDup() {
return isDup;
}
public MqttQoS qosLevel() {
return qosLevel;
}
/**
* 做 qos 降级，mqtt 规定 qos > 0，messageId 必须大于 0，为了兼容，固做降级处理
*/
void downgradeQos() {
this.qosLevel = MqttQoS.QOS0;
}
public boolean isRetain() {
return isRetain;
}
public int headLength() {
return headLength;
}
public int remainingLength() {
return remainingLength;
}
public int getMessageLength() {
return headLength + remainingLength;
}
@Override
public String toString() {
return "MqttFixedHeader[" +
"messageType=" + messageType +
", isDup=" + isDup +
", qosLevel=" + qosLevel +
", isRetain=" + isRetain +
", remainingLength=" + remainingLength +
']';
}
}