Mastering Spring 5.0

Unit testing validations

The following example shows how we can unit test the validations we added in:

     @Test     public void createTodo_withValidationError() throws Exception {       Todo mockTodo = new Todo(CREATED_TODO_ID, "Jack",        "Learn Spring MVC", new Date(), false);       String todo = "{"user":"Jack","desc":"Learn","done":false}";       when( service.addTodo(         anyString(), anyString(), isNull(), anyBoolean()))        .thenReturn(mockTodo);         MvcResult result = mvc.perform(         MockMvcRequestBuilders.post("/users/Jack/todos")        .content(todo)        .contentType(MediaType.APPLICATION_JSON))        .andExpect(           status().is4xxClientError()).andReturn();     }

Some important points to note are as follows:

• "desc":"Learn": We are using a desc value of length 5. This would cause a validation ...