JUnitでの例外テストの書き方

アノテーション利用

  @Test(expected = SampleException.class)
  public void throwsSampleException() {
    // do something
  }

try/catchでの書き方

  @Test
  public void throwsSampleException() {
    try {
      // do something
      ...

      fail();

    } catch (SampleException expected) {
      assertThat(expected.getMessage(), equalTo("exception message"));
    }
  }

Ruleを使った書き方

  @Rule
  public ExpectedException thrown = ExpectedException.none();

  @Test
  public void exceptionRule() {
    thrown.expect(SampleException.class);
    thrown.expectMessage("exception message");

    // do something
  }