Junit（JAVA）中找不到类异常

Question

I've seen similar questions however all are related to maven (I'm not using maven). I'm running intellij and have the Junit.jar 4.12 added in the library. I can create test methods and classes.

The problem is that when I try to run my TestRunner() main method i instantly get the following error

Exception in thread "main" java.lang.ClassNotFoundException: TestRunner
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:122)

And the code looks like this:

import junit.framework.TestSuite;
import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

public class TestRunner {
    public static void main(String[] args) {
        Result res = JUnitCore.runClasses(TestSuite.class);
        for (Failure fail : res.getFailures()) {
            System.out.println(fail.toString());
        }
        System.out.println(res.wasSuccessful());
    }
}

The thing that confuses me is that I had the exact same code in eclipse (for a previous project test) and it worked perfectly fine there. What am I missing?

• Closing and restarting intellij did not work.
• Re-importing libraries didn't change anything either.

Answer 1

Update, the problem was that I had not "Correctly" added the library. Apparently in Intellij, one must write @Test and then hit "Alt+enter" to prompt the auto fixes and choose the option to import JUnit that way. So it automatically adds it to the classpath. Which it didn't do properly if done manually.