Junit测试失败，没有失败跟踪

Question

I'm running JUnit tests from Eclipse, and using the command Assert.fail(message) whenever I want to cause the test to fail. The problem is that I always get the message along with the entire failure trace. Is there any way for JUnit to display the message only, without the stack trace?

Answer 1

Eclipse JUnit settings available via Window --> Preferences --> Java --> Junit allow for cutting stack traces for certain exception classes:

With these settings, the stack trace for the test:

@Test
public void test() {
    fail("Not yet implemented");
}

is filtered:

Now try to deselect the "org.junit.*" (or "junit.framework.Assert", depending which version of JUnit you're using), and rerun the test. The stack trace immediately becomes scary:

Perhaps this is the feature you're looking for.

Answer 2

If a test throws an error, the test will normally fail automatically without a message. You could of course catch Exceptions and let the test fail in the catch clause. Something like this:

@Test
public void test()  {
   try {
      // your test
  } catch (Exception e) {
      fail("I caught an " + e.class.getSimpleName());
   }
}

Of course as always when dealing with exceptions, be as precise when catching them as possible.

Answer 3

I found a way to crash the test without showing a long failure trace. Instead of using Assert.fail(), I create my own exception, and set the failure trace to be minimal:

public static void failTest(String message) throws MyTestFailure {
    System.err.println(message);
    MyTestFailure exception = new MyTestFailure(message);
    StackTraceElement elem = new StackTraceElement("com.my.package.Utils", "failTest", "failTest", 3);
    StackTraceElement elem1[] = new StackTraceElement[1];
    elem1[0] = elem;
    exception.setStackTrace(elem1);
    throw exception;
}

and this way I only print the message that I want to print, and a single line after that

Answer 4

I would simply override the printStackTrace()-methods for my custom Throwable:

• Exception -> ERROR

• AssertionError -> FAILURE

import java.io.PrintStream;
import java.io.PrintWriter;

public class TestErrorException extends Exception{

    private static final long serialVersionUID = -3486394019411535690L;
    private String message;

    public TestErrorException(String message) {
        this.message = message;
    }

    @Override
    public void printStackTrace() {
        System.err.println(message);
    }

    @Override
    public void printStackTrace(PrintStream s) {
        s.println(message);
    }

    @Override
    public void printStackTrace(PrintWriter s) {
        s.println(message);
    }

}