Untitled

public class ReversePolishEvaluator implements ExpressionEvaluator{		public int evaluate(ExpressionTokenizer et) throws TokenException	{		int first = 0;		int second = 0;		if(et.nextTokenType() != ExpressionTokenizer.TokenType.OP)		{						// label...			// call evaluate on label						// grabs first integer			first = et.nextInteger();						if(et.nextTokenType() == ExpressionTokenizer.TokenType.OP)				return first;								while(et.hasNextToken())			{						// gets results of computation				second = evaluate(et);				switch(et.nextOperator())				{					case '+':						first += second;						break;						case '-':						first -= second;						break;									case '*':						first *= second;						break;									case '/':						first /= second;						break;				}								if(et.nextTokenType() == ExpressionTokenizer.TokenType.OP) return first;			}		}		return first;			}	}