JUnitCore.runClasses() and @Test(timeout)

Hello I have the following code:

public class While {
  public static void whileTrue (){
    while (true) {}
  }
}

---

import org.junit.Test;
public class WhileTest {
  @Test(timeout = 1000)
  public void testWhileTrue() {
    While.whileTrue();
  }
}

---

import org.junit.runner.JUnitCore;
public class RunTests {
  public static void main(String[] args) {
    JUnitCore.runClasses(WhileTest.class);
  }
}

By running the main-method I expected, that the test-method terminat after 1000 ms. But nothing terminat. Is this a bug or is there something wrong by using the runClasses-method?

[schlagi123]

The extra thread for timed test ist ok, but i expected, that junit kill all created threads when its finished

[schlagi123]

I found out, that the main-thread terminat, but there is a new thread with the test. This thread not terminat.