/*
    * Copyright 2012 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.serialization;
  
  import java.util.Map;
  
  class CachingClassResolver implements ClassResolver {
  
      private final Map<String, Class<?>> classCache;
      private final ClassResolver delegate;
  
      CachingClassResolver(ClassResolver delegate, Map<String, Class<?>> classCache) {
          this.delegate = delegate;
          this.classCache = classCache;
      }
  
      @Override
      public Class<?> resolve(String className) throws ClassNotFoundException {
          // Query the cache first.
          Class<?> clazz;
          clazz = classCache.get(className);
          if (clazz != null) {
              return clazz;
          }
  
          // And then try to load.
          clazz = delegate.resolve(className);
  
          classCache.put(className, clazz);
          return clazz;
      }
  
  }