code: public static Object getDefaultPrimitiveValue(Class clazz) {
          if (clazz == int.class) {
              return 0;
          } else if (clazz == boolean.class) {
              return false;
          } else if (clazz == long.class) {
              return 0L;
          } else if (clazz == byte.class) {
              return (byte) 0;
          } else if (clazz == double.class) {
              return 0d;
          } else if (clazz == short.class) {
              return (short) 0;
          } else if (clazz == float.class) {
              return 0f;
          } else if (clazz == char.class) {
              return (char) 0;
          } else {
              return null;
          }
      }
docs: 得到基本类型的默认值
  
  @param clazz Class类
  @return 默认值