title: Eclipse keep saying "No tests found with test runner JUnit 5"
body: <p>I am using Eclipse Oxygen.3 Release (4.7.3). The following is my JUnit test class:</p>
  
  <pre class="lang-java prettyprint-override"><code>import static org.junit.Assert.assertEquals;
  
  import org.junit.After;
  import org.junit.AfterClass;
  import org.junit.Before;
  import org.junit.BeforeClass;
  import org.junit.Test;
  
  class MyMathTest {
      MyMath myMath = new MyMath();
  
      @Before
      public void before() {
          System.out.println("Before");
      }
  
      @After
      public void after() {
          System.out.println("After");
      }
  
      @Test
      public void testSum_with3numbers() {
          System.out.println("Test1");
          int result = myMath.sum(new int[] {1,2,3});
          int expected = 6;
          assertEquals(expected, result);
      }
  
      @Test
      public void testSum_with1numbers() {
          System.out.println("Test2");
          int result = myMath.sum(new int[] {3});
          int expected = 3;
          assertEquals(expected, result);
      }
  
      @BeforeClass
      public static void beforeClass() {
          System.out.println("Before class");
      }
  
      @AfterClass
      public static void afterClass() {
          System.out.println("After class");
      }
  
  }
  </code></pre>
  
  <p>When I run this Junit test, eclipse keeps popping up dialog telling <strong>"No tests found with test runner 'JUnit 5'"</strong>. Why?</p>
  
  <p><a href="https://i.stack.imgur.com/p7I9T.png" rel="noreferrer"><img src="https://i.stack.imgur.com/p7I9T.png" alt="enter image description here"></a></p>