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   /*
    * 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 io.netty.handler.codec.mqtt;
  
  import io.netty.util.internal.StringUtil;
  
  /**
   * Variable Header containing only Message Id
   * See <a href="https://public.dhe.ibm.com/software/dw/webservices/ws-mqtt/mqtt-v3r1.html#msg-id">MQTTV3.1/msg-id</a>
   */
  public class MqttMessageIdVariableHeader {
  
      private final int messageId;
  
      public static MqttMessageIdVariableHeader from(int messageId) {
        if (messageId < 1 || messageId > 0xffff) {
          throw new IllegalArgumentException("messageId: " + messageId + " (expected: 1 ~ 65535)");
        }
        return new MqttMessageIdVariableHeader(messageId);
      }
  
      protected MqttMessageIdVariableHeader(int messageId) {
          this.messageId = messageId;
      }
  
      public int messageId() {
          return messageId;
      }
  
      @Override
      public String toString() {
          return new StringBuilder(StringUtil.simpleClassName(this))
              .append('[')
              .append("messageId=").append(messageId)
              .append(']')
              .toString();
      }
  
      public MqttMessageIdAndPropertiesVariableHeader withEmptyProperties() {
          return new MqttMessageIdAndPropertiesVariableHeader(messageId, MqttProperties.NO_PROPERTIES);
      }
  
      MqttMessageIdAndPropertiesVariableHeader withDefaultEmptyProperties() {
          return withEmptyProperties();
      }
  }