public static boolean expressionIsTrue(double leftSide,Operator operator,double rightSide){
  final String expression=leftSide + operator.getMathematicalOperator() + rightSide;
  return expressionIsTrue(expression);
}

public static boolean expressionIsTrue ( double leftSide , Operator operator , double rightSide ) { final String expression = leftSide + operator . getMathematicalOperator ( ) + rightSide ; return expressionIsTrue ( expression ) ; }
evaluates whether an expression is true or false .
