Mocking static 方法抛出参数错误

Question

I have custom Log4j2 appender:

    @Plugin(
            name = "MyAppender",
            category = "Core",
            elementType = Appender.ELEMENT_TYPE)
    public class MyAppender extends AbstractAppender {
    
        private static final Logger LOGGER = LoggerFactory.getLogger(MyAppender.class);
        private final Lock lock = new ReentrantLock();
    
    
        private MyAppender(final String name, final Layout<? extends Serializable> layout ) {
            super(name, null, layout, false, Property.EMPTY_ARRAY);
        }
    
    
        @Override
        public void append(LogEvent event) {
           ....
        }
    
        @PluginFactory
        public static MyAppender createAppender(
                @PluginAttribute("name") String name,
                @PluginElement("Layout") Layout<? extends Serializable> layout){
            if (layout == null) {
                layout = PatternLayout.createDefaultLayout();
            }
            return new MyAppender(name, layout);
        }
}

And i want to mock the createAppenderMethod :

 try (MockedStatic<MyAppender> mocked = mockStatic(MyAppender.class)) {
            MyAppender appender = Mockito.mock(MyAppender.class);
            mocked.when(() -> MyAppender.createAppender("myAppender", Mockito.any(Layout.class))).thenReturn(appender);
              ....
        }

However this trows

org.mockito.exceptions.misusing.WrongTypeOfReturnValue: MyAppender cannot be returned by toString() toString() should return String

I tried to implement toString() method but the error remains the same.

If u use mocked.when(() -> MyAppender.createAppender("myAppender", Mockito.anyObject())).thenReturn(appender);

then i recieve:

org.mockito.exceptions.misusing.MissingMethodInvocationException: when() requires an argument which has to be 'a method call on a mock'. For example: when(mock.getArticles()).thenReturn(articles);

Why is this happening? What is the correct way to mock this? So far this way of mocking static methods worked for me

Answer 1

As per my understanding mocking static methods are not good to follow as it challenges the design level decision. Kindly someone guide me if am wrong.