Do not write catch blocks to pass a unit test. Consider the following example where a Calculator program has a divide method. It takes two integers, divides, and returns a result. When divide encounters a divide by zero, the program should throw an exception. The following is the code:

public class Calculator {

  public int divide(int op1, int op2)  {
    return op1/op2;
  }
}

The following is the test:

@Test
public void divideByZero_throws_exception() throws Exception {
  try {
    calc.divide(1, 0);
    fail("Should not reach here");
  } catch (ArithmeticException e) {

  }
}

Instead of catching ArithmeticException, we can apply the JUnit 4 pattern as follows:

  @Test(expected = ArithmeticException.class)
  public void divideByZero_throws_exception() throws Exception...