package backend.controller;

import backend.BackendConfiguration;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.IntegrationTest;
import org.springframework.boot.test.SpringApplicationConfiguration;
import org.springframework.http.MediaType;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;

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.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = BackendConfiguration.class)
@WebAppConfiguration
@IntegrationTest("server.port:0")
public class HelloWorldControllerTest {

    @Autowired
    private WebApplicationContext context;
    private MockMvc mockMvc;

    @Before
    public void setUp() {
        mockMvc = MockMvcBuilders.webAppContextSetup(context).build();
    }

    @Test
    public void saysHello() throws Exception {
        mockMvc.perform(get("/"))
                .andExpect(status().isOk())
                .andExpect(content().contentType(MediaType.APPLICATION_JSON_VALUE))
                .andExpect(jsonPath("content").value("Hello and welcome to BreakOut, Stranger!"));
    }

}

package backend.controller;

import backend.BackendConfiguration;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.IntegrationTest;
import org.springframework.boot.test.SpringApplicationConfiguration;
import org.springframework.http.MediaType;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;

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.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = BackendConfiguration.class)
@WebAppConfiguration
@IntegrationTest("server.port:0")
public class HelloWorldControllerTest {

    @Autowired
    private WebApplicationContext context;
    private MockMvc mockMvc;

    @Before
    public void setUp() {
        mockMvc = MockMvcBuilders.webAppContextSetup(context).build();
    }

    @Test
    public void saysHello() throws Exception {
        mockMvc.perform(get("/helloworld"))
                .andExpect(status().isOk())
                .andExpect(content().contentType(MediaType.APPLICATION_JSON_VALUE))
                .andExpect(jsonPath("content").value("Hello and welcome to BreakOut, Stranger!"));
    }

}

Fix integration test for "/helloworld"