code: public Object constantValue() {
          Object result = sym.getConstValue();
          if (result != null && sym.type.hasTag(BOOLEAN))
              // javac represents false and true as Integers 0 and 1
              result = Boolean.valueOf(((Integer)result).intValue() != 0);
          return result;
      }
docs: Get the value of a constant field.
  
  @return the value of a constant field. The value is
  automatically wrapped in an object if it has a primitive type.
  If the field is not constant, returns null.