不能用Eclipse运行junit

我用新的Eclipse。使用JUnit创建演示测试(我添加了默认的JUnit库内置Eclipse)。然后我写这个代码:

import junit.framework.*;

import org.junit.Test;

public class SimpleTest extends TestCase { 
   public SimpleTest(String name) { 
      super(name);
   }
   public final void main(String method){

   }

   @Test
   public final void testSimpleTest() {
      int answer = 2;
      assertEquals((1+1), answer); 
   }
}

但它不运转。在“调试”选项卡中:

org.eclipse.jdt.internal.junit.runner.RemoteTestRunner at localhost:52754 
Thread [main] (Suspended (exception ClassNotFoundException)) 
URLClassLoader$1.run() line: not available [local variables unavailable] 
AccessController.doPrivileged(PrivilegedExceptionAction<T>, AccessControlContext) line: not available [native method] 
Launcher$AppClassLoader(URLClassLoader).findClass(String) line: not available 
Launcher$AppClassLoader(ClassLoader).loadClass(String, boolean) line: not available 
Launcher$AppClassLoader.loadClass(String, boolean) line: not available 
Launcher$AppClassLoader(ClassLoader).loadClass(String) line: not available 

我怎么解决这个问题?