【Spring boot】编写代码及测试用例入门之 Hello Spring boot _踩坑记

缺乏、安全感 2022-05-26 20:08 161阅读 0赞

先贴下目录：  
![这里写图片描述][70]

这是我从 `start.spring.io` 里下载的依赖Web的模板

// DemoApplication.java
    package com.abloume.springboot.blog.demo;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    // 这里有一个坑，没有注册扫描器，下面分析时会有说明
    public class DemoApplication { 
    
        public static void main(String[] args) {
            SpringApplication.run(DemoApplication.class, args);
        }
    }

// HelloController.java
    package com.abloume.springboot.blog.controller;
    
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    @RestController 
    // 使用 @RestController 相当于 @Controller 和 @RequestBody
    public class HelloController {
        @RequestMapping("/hello")
        public String hello() {
            return "Hello Spring boot!";
        }
    }

// DemoApplicationTests
    package com.abloume.springboot.blog.demo;
    
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.test.context.junit4.SpringRunner;
    
    @RunWith(SpringRunner.class)
    @SpringBootTest
    public class DemoApplicationTests {
    
        @Test
        public void contextLoads() {
        }
    
    }

// HelloControllerTest
    package com.abloume.springboot.blog.controller;
    
    import com.abloume.springboot.blog.demo.DemoApplication;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.http.MediaType;
    import org.springframework.test.context.junit4.SpringRunner;
    import org.springframework.test.web.servlet.MockMvc;
    import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
    
    import static org.hamcrest.core.IsEqual.equalTo;
    import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
    import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
    
    
    @RunWith(SpringRunner.class)
    @SpringBootTest // 这里有一个配置坑
    @AutoConfigureMockMvc
    public class HelloControllerTest {
    
        @Autowired
        private MockMvc mockMvc;
        @Test
        public void testHello() throws Exception {
            mockMvc.perform(MockMvcRequestBuilders.get("/hello").accept(MediaType.APPLICATION_JSON))
                    .andExpect(status().isOk())
                    .andExpect(content().string(equalTo("Hello Spring boot!")));
        };
    };

下面贴上自己的报错图及解决方案：  
![这里写图片描述][70 1]  
解决方案：

// 这里需要指定它的启动类
    @SpringBootTest(classes = DemoApplication.class)

![这里写图片描述][70 2]  
报错404说明路径错误匹配不到，但前后路径是对应的都是 `"/hello"`；

再仔细看 `HelloController.java` 发现未被使用  
![这里写图片描述][70 3]  
解决方案：需要在启动类中添加扫描注解即可  
![这里写图片描述][70 4]  
浏览器上运行看一下，Ok~  
![这里写图片描述][70 5]

[70]: /images/20220527/84851dab1584440a942b013100351968.png
[70 1]: /images/20220527/0a35d9ba01c1422aadaddf47b89c852e.png
[70 2]: /images/20220527/8f14bd6d65654eaea15c6a0c827d432a.png
[70 3]: /images/20220527/77d780e6ed6247329810bb9843b9e11b.png
[70 4]: /images/20220527/ea15e7013b16412a82802779893352f0.png
[70 5]: /images/20220527/a16179943613486898a8a20ad43e97a6.png