import org.easymock.EasyMock; public class ExampleTest { public void test() { String str = null; EasyMock.assertNotNull(str); // This will fail, since str is null } }In this example, we are using EasyMock to verify that the string `str` is not null. However, since we have not yet assigned a value to `str`, this test will fail. This method is part of the org.easymock package library.