content: package com.alibaba.fastjson.serializer;
  
  import java.util.HashSet;
  import java.util.Set;
  
  /*
   * Copyright 1999-2018 Alibaba Group.
   *
   * Licensed 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.
   */
  public class SimplePropertyPreFilter implements PropertyPreFilter {
  
      private final Class<?>    clazz;
      private final Set<String> includes = new HashSet<String>();
      private final Set<String> excludes = new HashSet<String>();
      private int               maxLevel = 0;
  
      public SimplePropertyPreFilter(String... properties){
          this(null, properties);
      }
  
      public SimplePropertyPreFilter(Class<?> clazz, String... properties){
          super();
          this.clazz = clazz;
          for (String item : properties) {
              if (item != null) {
                  this.includes.add(item);
              }
          }
      }
      
      /**
       * @since 1.2.9
       */
      public int getMaxLevel() {
          return maxLevel;
      }
      
      /**
       * @since 1.2.9
       */
      public void setMaxLevel(int maxLevel) {
          this.maxLevel = maxLevel;
      }
  
      public Class<?> getClazz() {
          return clazz;
      }
  
      public Set<String> getIncludes() {
          return includes;
      }
  
      public Set<String> getExcludes() {
          return excludes;
      }
  
      public boolean apply(JSONSerializer serializer, Object source, String name) {
          if (source == null) {
              return true;
          }
  
          if (clazz != null && !clazz.isInstance(source)) {
              return true;
          }
  
          if (this.excludes.contains(name)) {
              return false;
          }
          
          if (maxLevel > 0) {
              int level = 0;
              SerialContext context = serializer.context;
              while (context != null) {
                  level++;
                  if (level > maxLevel) {
                      return false;
                  }
                  context = context.parent;
              }
          }
  
          return includes.size() == 0
                  || includes.contains(name);
      }
  
  }
  