Thread: how could I throw an exception in this case

guys, I'm reading a formula from file like: 2 + 2 - ( 3 - 1 ) * 3 $, but I want to be able to throw an exception if there are two operands together like: 2 + 2 3 * 4 $ or if there are two operators together like: 2 + + 3 $.

here's what I have so far, the operator part the program detects it, but I'm having problem with two operands together. I would like to throw the exception where "Bad Formula!..." is

while(in.hasNext())
        {
            String next = in.next();
            do
            {
                if (optor.isOperator(next)) 
                {
                    processOptor(next);
                    oprandCount = 0;
                } 
                else 
                {
                    if(oprandCount == 0)
                    {
                        oprand.push(Integer.parseInt(next));
                        strOut += next+" ";
                        oprandCount++;                        
                    }
                    else
                    {
                        System.out.println("Bad formula!...");
                        System.exit(0);
                    }
                }                                   
                next = in.next();
 
                if(next.equals("$"))
                    processOptor(next);
 
            }while(!next.equals("$"));

Originally Posted by mia_tech

I would like to throw the exception where "Bad Formula!..." is

...
                    else
                    {
                        // System.out.println("Bad formula!...");
                        // System.exit(0);
                       throw new Exception( "Bad formula, bad, bad!" );
...

How about that?