[FIXED] Spring Boot Unit Test returns 404 instead of 200

Issue

I am new in springboot. I am just watching the Spring in Action and programming follow the author.

then things get difficult when i just reading the chapter 1. I need to test a controller. the code in this book is:

package tacos;

import static org.hamcrest.Matchers.containsString;
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 static org.springframework.test.web.servlet.result.MockMvcResultMatchers.view;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.test.web.servlet.MockMvc;

@RunWith(SpringRunner.class)
@WebMvcTest(HomeController.class)   // <1>
public class HomeControllerTest {

  @Autowired
  private MockMvc mockMvc;   // <2>

  @Test
  public void testHomePage() throws Exception {
    mockMvc.perform(get("/"))    // <3>
    
      .andExpect(status().isOk())  // <4>
      
      .andExpect(view().name("home"))  // <5>
      
      .andExpect(content().string(           // <6>
          containsString("Welcome to...")));  
  }

}

I am using springboot 2.7.3 so i just remove @RunWith(SpringRunner.class) from my code. and i immediately get an error when do the test:

after google that i realized it might not find my controller so I add @Import(HomeController.class) to the test class. It looks like:

package com.qph.tacos;

import org.hamcrest.Matchers;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.context.annotation.Import;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import org.springframework.test.web.servlet.result.MockMvcResultMatchers;

@WebMvcTest(HomeControllerTest.class)
@Import(HomeController.class)
public class HomeControllerTest {
    @Autowired
    private MockMvc mockMvc;

    @Test
    public void testHomePage() throws Exception {
        mockMvc.perform(MockMvcRequestBuilders.get("/"))
                .andExpect(MockMvcResultMatchers.status().isOk())
                .andExpect(MockMvcResultMatchers.view().name("home"))
                .andExpect(MockMvcResultMatchers.content().string(Matchers.containsString("Welcome to...")));
    }
}

then it just pass the test!!!

now i just wonder why the code written by the author can pass the test without @Import(HomeController.class)?

my directory structure is like:

the controller to be tested is:

package com.qph.tacos;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;

@Controller
public class HomeController {
    @GetMapping("/")
    public String home() {
        // return the name of template
        return "home";
    }
}

I am new in springboot. maybe it's a simple question but i really spent so much time on it.

Thanks for your help!

Solution

Change to

@WebMvcTest(HomeController.class)

You should reference the controller under test with this annotation, otherwise it won't be loaded into the application context.

Answered By - Johan Nordlinder
Answer Checked By - Marilyn (JavaFixing Volunteer)