@Test public void subTwoNumbers(){ double resultSub = mCalculator.subtraction(2d, 1d); assertThat(resultSub, is(equalTo(1d))); }
public double subtraction(double firstOperand, double secondOperand) { return firstOperand - secondOperand; }
Calculator { public double subtraction(double firstOperand, double secondOperand) { return firstOperand - secondOperand; } }
Calculator { public double subtraction(double firstOperand, double secondOperand) { return firstOperand - secondOperand; }  }
Calculator { public double subtraction(double firstOperand, double secondOperand) { return firstOperand - secondOperand; }  double addition(double firstOperand, double secondOperand); double subtraction(double firstOperand, double secondOperand); double division(double firstOperand, double secondOperand); double multiplication(double firstOperand, double secondOperand); }
Calculator { public double subtraction(double firstOperand, double secondOperand) { return firstOperand - secondOperand; }  double addition(double firstOperand, double secondOperand); double subtraction(double firstOperand, double secondOperand); double division(double firstOperand, double secondOperand); double multiplication(double firstOperand, double secondOperand);  }