Question on addTest method of Junit

Hi, all, I got a question on the addTest method of TestSuite class. I wrote a TestSuite class with the static suite method like this:
public static Test suite() {
TestSuite suite = new TestSuite();
suite.addTestSuite(CalTest.class);
return suite;
}
where CalTest is a class inheriting from TestCase class. This part of code is ok. However if I change to this
public static Test suite() {
TestSuite suite = new TestSuite();
suite.addTest(new CalTest()); --- difference
return suite;
}
The launch of the testrunner fails and reports a AssertionFailedError. On the JUnit api doc, the addTest(Test test) method does not have any explanation. I would like to know what is wrong with the second method.

The default constructor doesn't tell Junit which test case to add to the suite. You need to call the constructor that takes a string. For example,


However, this only runs one test. If you want to run all the tests, as I suspect, you can add the whole test suite. There are two ways of doing this (one you already had)

Thank you, Jeanne. You solved my puzzle. I used to think the fName private field in the TestCase class indicates the name of the test class, a usual way in designing class though, it turns out this is the method name I want to run.