jmexprparse.java

类javaScript脚本解释器

        ckey = toParse[++JMParse.CurrPos];
        continue;
      }

      //处理数字类型的数据
      if ( (ckey > 47) && (ckey < 58)) {
        if (symbolType <= 0) {
          ParseSymbol(symbolType, key.toString(), stackCalc, cc);
          symbolType = 1;
        }
        key.append(ckey);
        ckey = toParse[++JMParse.CurrPos];
        continue;
      } //数值类型中不能有其他字符
      else if (symbolType == 1)
        throw new JMParseException("不正确的数字表示法");

      //未确定类型的数据
      if ( (ckey == 95) || (ckey > 64 && ckey < 91) ||
          (ckey > 96 && ckey < 123)) {
        if (symbolType <= 0) {
          ParseSymbol(symbolType, key.toString(), stackCalc, cc);
          symbolType = 5;
        }
        key.append(ckey);
        ckey = toParse[++JMParse.CurrPos];
        continue;
      }

      //处理字符串
      if (ckey == '"') {
        if (symbolType <= 0){
          ParseSymbol(symbolType, key.toString(), stackCalc, cc);
          symbolType = 2;
        }
        else if (symbolType == 2)
          symbolType = 3;
        else
          throw new JMParseException("非法的字符串起始符");
        ckey = toParse[++JMParse.CurrPos];
        continue;
      }

      //处理字符串中的转义符
      if (ckey == '\\') {
        if (symbolType != 2)
          throw new JMParseException("非法使用的转义符");
        JMParse.CurrPos++;
        key.append(toParse[JMParse.CurrPos]);
        ckey = toParse[++JMParse.CurrPos];
        continue;
      }

      //对象函数处理
      if (ckey == '.') {
        if (symbolType == 5) {
          symbolType = 7;
          //把解到的对象存入数组
          postfixExpr[cc.Value] = PropParse.ParseObject(PropParse.FindObject(key.toString()), toParse);
          cc.Inc();
        } else if (symbolType == 7 || symbolType == 6) {
          //如果是连续的或自定义函数返回对象的‘.‘则递归解释对象
          postfixExpr[cc.Value - 1] = PropParse.ParseObject(postfixExpr[cc.Value -1], toParse);
        }
        else throw new JMParseException("非法使用的对象方法引用符");
        ckey = toParse[JMParse.CurrPos];
        key = key.delete(0, 25);

        continue;
      }

      if (symbolType == 2){
        key.append(ckey);
        ckey = toParse[++JMParse.CurrPos];
        continue;
      } else throw new JMParseException(new StringBuffer("非法字符 \"").
                                 append(ckey).append("\" ").toString());
    }//while (ckey != 0)

    ParseSymbol(symbolType, key.toString(), stackCalc, cc);

    //令“#”字符出栈
    ParseSymbol(-1, "#", stackCalc, cc);

    if (cc.Value == 1)
      return postfixExpr[0];
    else if (cc.Value == 0)
      return null;


    //处理转化后的后缀表达式

    Object First = null;
    Object Second = null;
    String cs;
    int    Index = 0;

    for (int i = 0; i < cc.Value; i ++){
      if (!isOperator[i])
        stackCalc.push(postfixExpr[i]);
      else {
        Index = ((Integer)postfixExpr[i]).intValue();
        if (Index == LEFT_PARENTHESES || Index == RIGHT_PARENTHESES)
          throw new JMParseException("非法使用的圆括号");
        try {
          Second = stackCalc.pop();
          cs = Second.getClass().getName();
          if (JMParse.COptpriority[Index + 1] == 2)
            First = stackCalc.pop();
          switch(Index) {
            case PLUS:
              if (cs.equals("java.lang.Integer"))
                stackCalc.push( new Integer(((Integer)First).intValue() +
                                           ((Integer)Second).intValue()));
              else if (cs.equals("java.lang.String"))
                stackCalc.push( new StringBuffer(First.toString()).append(Second.toString()));

              break;
            case MINUS:
              stackCalc.push( new Integer(((Integer)First).intValue() -
                                         ((Integer)Second).intValue()));
              break;
            case MULTIPLY:
              stackCalc.push( new Integer(((Integer)First).intValue() *
                                         ((Integer)Second).intValue()));
              break;
            case DIVIDE:
              stackCalc.push( new Integer(((Integer)First).intValue() /
                                         ((Integer)Second).intValue()));
              break;
            case PER_CENT:
              stackCalc.push( new Integer(((Integer)First).intValue() %
                                         ((Integer)Second).intValue()));
              break;
            case A:
              int x = ((Integer)First).intValue();
              int z = ((Integer)Second).intValue();
              if (z == 0) x = 1;
              else if (z == -1) x = 1/x;
              else if (z != 1) {
                for (int y = 0; y < z - 1; y++)
                  x = x * x;
              }
              stackCalc.push(new Integer(x));
              break;
            case LESS:
              stackCalc.push( new Boolean(((Integer)First).intValue() <
                                         ((Integer)Second).intValue()));
              break;
            case MORE:
              stackCalc.push( new Boolean(((Integer)First).intValue() >
                                         ((Integer)Second).intValue()));
              break;
            case LESS_EQUAL:
              stackCalc.push( new Boolean(((Integer)First).intValue() <=
                                         ((Integer)Second).intValue()));
              break;
            case MORE_EQUAL:
              stackCalc.push( new Boolean(((Integer)First).intValue() >=
                                         ((Integer)Second).intValue()));
              break;
            case EQUAL:
              if (cs.equals("java.lang.Integer"))
                stackCalc.push( new Boolean(((Integer)First).intValue() ==
                                           ((Integer)Second).intValue()));
              else if (cs.equals("java.lang.Boolean"))
                stackCalc.push( new Boolean(((Boolean)First).booleanValue() ==
                                           ((Boolean)Second).booleanValue()));
              else if (cs.equals("java.lang.String"))
                stackCalc.push( new Boolean(((String)First).equals(Second)));
              break;
            case NOTEQUAL:
              if (cs.equals("java.lang.Integer"))
                stackCalc.push( new Boolean(((Integer)First).intValue() !=
                                           ((Integer)Second).intValue()));
              else if (cs.equals("java.lang.Boolean"))
                stackCalc.push( new Boolean(((Boolean)First).booleanValue() !=
                                           ((Boolean)Second).booleanValue()));
              else if (cs.equals("java.lang.String"))
                throw new JMParseException("不支持的字符串操作“！”");
              break;
            case NOT:
              stackCalc.push(new Boolean(!((Boolean)Second).booleanValue()));
              break;
            case AND:
              stackCalc.push( new Boolean(((Boolean)First).booleanValue() &&
                                         ((Boolean)Second).booleanValue()));
              break;
            case OR:
              stackCalc.push( new Boolean(((Boolean)First).booleanValue() ||
                                         ((Boolean)Second).booleanValue()));
          }// end switch
        } catch (ClassCastException e){
          throw new JMParseException(new StringBuffer("操作数不支持的操作“").
            append(JMParse.Operator.substring(Index, Index + JMParse.COptpriority[Index + 1])).
            append("”").toString());
        } catch (EmptyStackException e) {
          throw new JMParseException(new StringBuffer("缺少操作数“").
            append(JMParse.Operator.substring(Index, Index + JMParse.COptpriority[Index + 1])).
            append("”").toString());
        }
        catch (Exception e){
          throw new JMParseException(e.getMessage());
        }

      } //end if !Operator

    }   //end for (int i = 0; i < peCurrIndex; i ++)

    if (stackCalc.size() > 1)
      throw new JMParseException("丢失操作符");
    else if(stackCalc.size() == 0)
      throw new JMParseException("丢失操作数或\")\"");
    else if (stackCalc.size() == 1)
      return stackCalc.pop();
    return null;
  }

}