Re: How do I use Junit to test whether catch the Exception

From:

Joe Attardi <jattardi@gmail.com>

Newsgroups:

comp.lang.java.programmer,comp.lang.java.help

Date:

Thu, 13 Sep 2007 15:31:12 -0400

Message-ID:

<GIOdnVrKHuCdDXTbnZ2dnUVZ_r_inZ2d@comcast.com>

Daniel Dyer wrote:

I think the OP wants to do it the other way round, i.e. fail if the
exception is not thrown. You'd probably have to set a flag in the catch
block and check it in a finally block, as Manish suggested.

Or you could have an empty catch block, and just add a call to fail()
right after the method call:

try {
   myMethod();
   fail("IOException was not thrown!");
} catch (IOException ioe) {
    // This is expected!
}

If the exception doesn't get thrown, execution continues to the next
line, which is the call to fail(). If it does get thrown, which we want,
that fail() will be skipped since we jump to the catch block.

TestNG makes this easy type of check easy:

    @Test(expectedExceptions = IOException.class)
    public void myTest()
    {
        myMethod();
    }

Yup. I love TestNG.
Although, I think I remember reading that the latest and greatest JUnit
has added an annotation to expect an exception... but I'm not sure at
the moment.

--
Joe Attardi | Massachusetts, USA
jattardi@gmail.com | http://thinksincode.blogspot.com/