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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;
  
  public enum MqttQoS {
      AT_MOST_ONCE(0),
      AT_LEAST_ONCE(1),
      EXACTLY_ONCE(2),
      FAILURE(0x80);
  
      private final int value;
  
      MqttQoS(int value) {
          this.value = value;
      }
  
      public int value() {
          return value;
      }
  
      public static MqttQoS valueOf(int value) {
          switch (value) {
          case 0:
              return AT_MOST_ONCE;
          case 1:
              return AT_LEAST_ONCE;
          case 2:
              return EXACTLY_ONCE;
          case 0x80:
              return FAILURE;
          default:
              throw new IllegalArgumentException("invalid QoS: " + value);
          }
      }
  }