Question

Write a method that computes the value of an arithmetic expression. The operator string should be one of ("+", "-", "*", or "/"). The method should throw an IllegalArgumentException otherwise. Also throw an IllegalArgumentException if the operator is "/" and the second argument is zero.

Answer 1

The method named computeExpression calculates an arithmetic expression with two operands and an operator. It checks for valid operators (+, -, *, /) and for division by zero, throwing IllegalArgumentException in case of errors.

Step-by-step explanation:

To compute the value of an arithmetic expression using a given operator and two operands, you can write a method in a programming language such as Java. The method should check the validity of the operator and the operands, and perform the calculation accordingly. If the operator is not one of the specified "+," "-," "*," or "/", or if division by zero is attempted, the method should throw an IllegalArgumentException.

Example Method

public double computeExpression(double operand1, double operand2, String operator) {
switch (operator) {
case "+":
return operand1 + operand2;
case "-":
return operand1 - operand2;
case "*":
return operand1 * operand2;
case "/":
if (operand2 == 0) {
throw new IllegalArgumentException("Division by zero is not allowed.");
}
return operand1 / operand2;
default:
throw new IllegalArgumentException("Invalid operator.");
}
}
The computeExpression method above takes in two double values and a string representing the operator. It uses a switch statement to determine which arithmetic operation to perform. Remember to handle exceptions and edge cases like division by zero to ensure the method is robust.

Answer 2

To compute the value of an arithmetic expression, create a method that takes two numbers and an operator as input. Use a switch statement to perform the appropriate arithmetic operation based on the operator. Handle division by zero and invalid operators by throwing an IllegalArgumentException.

Step-by-step explanation:

To compute the value of an arithmetic expression using the given operator, you can create a method that takes in three parameters: two numbers and a string representing the operator.

The method can then use a switch statement to perform the appropriate arithmetic operation based on the operator. For example, if the operator is '+', you can add the two numbers together.

Here is an example implementation of the method in Java:

public static double computeExpression(double num1, double num2, String operator) {
switch(operator) {
case "+":
return num1 + num2;
case "-":
return num1 - num2;
case "*":
return num1 * num2;
case "/":
if (num2 == 0) {
throw new IllegalArgumentException("Cannot divide by zero!");
}
return num1 / num2;
default:
throw new IllegalArgumentException("Invalid operator!");
}
}

This method handles the four basic arithmetic operators: '+', '-', '*', and '/'. If the operator is '/' and the second argument is zero, it throws an IllegalArgumentException to handle division by zero. If the operator is any other string, it also throws an IllegalArgumentException to indicate an invalid operator.