Mockito spy

淩亂°似流年 2022-11-13 00:54 102阅读 0赞

List list = new LinkedList();
       List spy = spy(list);
    
       //optionally, you can stub out some methods:
       when(spy.size()).thenReturn(100);
    
       //using the spy calls *real* methods
       spy.add("one");
       spy.add("two");
    
       //prints "one" - the first element of a list
       System.out.println(spy.get(0));
    
       //size() method was stubbed - 100 is printed
       System.out.println(spy.size());
    
       //optionally, you can verify
       verify(spy).add("one");
       verify(spy).add("two");

需要注意的是：when和doReturn的使用场景。spy会导致方法执行进入真实逻辑，如果不希望进入方法内部执行，应该使用doReturn的形式。

List list = new LinkedList();
       List spy = spy(list);
    
       //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
       when(spy.get(0)).thenReturn("foo");
    
       //You have to use doReturn() for stubbing
       doReturn("foo").when(spy).get(0);

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3d0X2JldHRlcg_size_16_color_FFFFFF_t_70]

还有需要注意的点是：如果spy的是一个接口，会有问题，必须指定对应的实现类spy。

参考：[https://javadoc.io/doc/org.mockito/mockito-core/latest/org/mockito/Mockito.html\#doReturn-java.lang.Object-][https_javadoc.io_doc_org.mockito_mockito-core_latest_org_mockito_Mockito.html_doReturn-java.lang.Object-]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3d0X2JldHRlcg_size_16_color_FFFFFF_t_70]: /images/20221022/fde0ee7ff4ce42bd9c1e18f0cf4a64df.png
[https_javadoc.io_doc_org.mockito_mockito-core_latest_org_mockito_Mockito.html_doReturn-java.lang.Object-]: https://javadoc.io/doc/org.mockito/mockito-core/latest/org/mockito/Mockito.html#doReturn-java.lang.Object-