package com.example.spring_test;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringJUnitTestStartup {

    public static void main(String[] args) {
        SpringApplication.run(SpringJUnitTestStartup.class);
    }
}

3. Chúng ta cần tạo ra lớp <code>BaseIntegrationTest</code> thế này:

   package com.example.spring_test.test;
   
   import org.junit.jupiter.api.extension.ExtendWith;
   import org.springframework.boot.test.context.SpringBootTest;
   import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
   import org.springframework.boot.test.mock.mockito.MockBean;
   import org.springframework.context.ApplicationContextInitializer;
   import org.springframework.context.ConfigurableApplicationContext;
   import org.springframework.context.annotation.Bean;
   import org.springframework.test.context.ContextConfiguration;
   import org.springframework.test.context.junit.jupiter.SpringExtension;
   
   import com.example.spring_test.SpringJUnitTestStartup;
   import com.example.spring_test.service.GoodByeService;
   import com.example.spring_test.test.BaseIntegrationTest.Initializer;
   import com.example.spring_test.test.BaseIntegrationTest.SomeTestConfiguration;
   
   @ExtendWith(SpringExtension.class)
   @SpringBootTest(
       classes = SpringJUnitTestStartup.class,
       webEnvironment = WebEnvironment.DEFINED_PORT
   )
   @ContextConfiguration(
       initializers = Initializer.class,
       classes = SomeTestConfiguration.class
   )
   public class BaseIntegrationTest {
   
       @MockBean
       protected GoodByeService goodByeService;
   
       public static class Initializer
           implements ApplicationContextInitializer {
   
           @Override
           public void initialize(ConfigurableApplicationContext applicationContext) {
               // init something
           }
       }
   
       public static class SomeTestConfiguration {
   
           @Bean
           public Object someBean() {
               return "someBean";
           }
       }
   }
   

4. Cuối cùng chúng ta sẽ tạo ra lớp <code>GoodbyeControllerTest</code> thế này:

   package com.example.spring_test.test;
   
   import static org.mockito.Mockito.times;
   import static org.mockito.Mockito.verify;
   import static org.mockito.Mockito.when;
   import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
   import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
   import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
   
   import org.junit.jupiter.api.Test;
   import org.springframework.beans.factory.annotation.Autowired;
   import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
   import org.springframework.test.web.servlet.MockMvc;
   
   @AutoConfigureMockMvc
   public class GoodbyeControllerTest extends BaseIntegrationTest {
   
       @Autowired
       private MockMvc mockMvc;
   
       @Test
       public void helloAndGoodByeTest() throws Exception {
           // given
           final String who = "World";
           final String goodBye = "I will never say good bye";
           when(goodByeService.goodBye(who)).thenReturn(goodBye);
   
           // when
           // then
           final String expected = "Hello World! and " + goodBye;
           mockMvc.perform(get("/hello-and-goodbye?who=World"))
                  .andExpect(status().isOk())
                  .andExpect(content().string(expected));
   
           verify(goodByeService, times(1)).goodBye(who);
       }
   }