Do not display stacktrace of thrown exception messages in JUnit test

Question

While testing for message value of thrown exception messages like this:

public void mustFailIfTheActionDoesNotExist() {
        try {
            getAction(UUID.randomUUID().toString());

            fail("Must fail if the action does not exists");
        } catch (MyException ex) {
            Assert.assertEquals("Exception generated on action", ex.getMessage());
        }

the exception and their stacktrace are visible on the terminal. As I have hundreds of classes in my project, the terminal just becomes a long list of stacktraces of exception messages.

Is there a way to suppress the stack-trace of exception output to screen/terminal when Junit tests are run?

PS: I don't want to suppress logging for all unit tests, just in specific cases.

Answer 1

I'm guessing that the code you are testing is logging an exception and throwing it. Don't do that.

When catching an exception in non-test code, do one of these:

1. Log the exception and move on
2. Rethrow the exception without logging it
3. Wrap the exception and throw the wrapped exception without doing any logging

If you do this, then any exception will get logged at most once.

You also should ensure that all exceptions are logged at the top level of your code. This may require calling Thread.setDefaultUncaughtExceptionHandler() or `Thread.setUncaughtExceptionHandler()