java - 您如何断言在JUnit 4测试中引发了某种异常？(How do you assert that a certain exception is thrown in JUnit 4 tests?)

Question

How can I use JUnit4 idiomatically to test that some code throws an exception?

(如何惯用JUnit4来测试某些代码引发异常？)

While I can certainly do something like this:

(虽然我当然可以做这样的事情：)

@Test
public void testFooThrowsIndexOutOfBoundsException() {
  boolean thrown = false;

  try {
    foo.doStuff();
  } catch (IndexOutOfBoundsException e) {
    thrown = true;
  }

  assertTrue(thrown);
}

I recall that there is an annotation or an Assert.xyz or something that is far less kludgy and far more in-the-spirit of JUnit for these sorts of situations.

(我记得在这种情况下，有一个批注或一个Assert.xyz或一些不那么杂乱无章的东西 ，更是JUnit的精髓。)

  ask by SCdF translate from so

Answer 1

JUnit 4 has support for this:

(JUnit 4为此提供支持：)

@Test(expected = IndexOutOfBoundsException.class)
public void testIndexOutOfBoundsException() {

    ArrayList emptyList = new ArrayList();
    Object o = emptyList.get(0);

}

Reference :

(参考：)

• JUnit Test-FAQ

  (JUnit测试常见问题解答)