content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF 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
   *
   *     http://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 com.alipay.remoting.config;
  
  import java.util.concurrent.ConcurrentHashMap;
  
  /**
   * Option carrier.
   *
   * @author chengyi (mark.lx@antfin.com) 2018-11-06 17:42
   */
  public class BoltOptions {
  
      private ConcurrentHashMap<BoltOption<?>, Object> options = new ConcurrentHashMap<BoltOption<?>, Object>();
  
      /**
       * Get the optioned value.
       * Return default value if option does not exist.
       *
       * @param option target option
       * @return the optioned value of default value if option does not exist.
       */
      @SuppressWarnings("unchecked")
      public <T> T option(BoltOption<T> option) {
          Object value = options.get(option);
          if (value == null) {
              value = option.defaultValue();
          }
  
          return value == null ? null : (T) value;
      }
  
      /**
       * Set up an new option with specific value.
       * Use a value of {@code null} to remove a previous set {@link BoltOption}.
       *
       * @param option target option
       * @param value option value, null for remove a previous set {@link BoltOption}.
       * @return this BoltOptions instance
       */
      public <T> BoltOptions option(BoltOption<T> option, T value) {
          if (value == null) {
              options.remove(option);
              return this;
          }
  
          options.put(option, value);
          return this;
      }
  }
  