content: package com.alibaba.json.test.a;
  
  import com.alibaba.fastjson.serializer.SerializerFeature;
  
  public class SpecialTest {
      
      public static void main(String[] args) throws Exception {
          
          int count = 0;
          for (int i = 0; i < 1000; ++i) {
              char ch = (char) i;
              if(isSpecial(ch, 0)) {
                  count++;
              }
          }
          System.out.println(count);
      }
      static boolean isSpecial(char ch, int features) {
          // if (ch > ']') {
          // return false;
          // }
          
          if (ch == ' ') { // 32
              return false;
          }
  
          if (ch == '/') { // 47
              return SerializerFeature.isEnabled(features, SerializerFeature.WriteSlashAsSpecial);
          }
  
          if (ch > '#' // 35
              && ch != '\\' // 92
              ) {
              return false;
          }
  
          if (ch <= 0x1F // 31
                  || ch == '\\' // 92
                  || ch == '"' // 34
                  ) {
              return true;
          }
  
          return false;
      }
  }
  