Spring Boot 知识点速记

本文是学习2小时学会Spring Boot和Spring Boot进阶之Web进阶的SpringBoot常用知识点速记。

SpringBoot前置知识：

• Spring：相关资料参考Spring知识点速查
• Maven：相关资料参考Maven知识点速查

项目属性配置

配置项

resources/application.yml

girl:
  cupSize: B
  age: 18

自动注入类中

@Component
@ConfigurationProperties(prefix = "girl")
public class GirlProperties {
    private String cupSize;
    private Integer age;

    public String getCupSize() {
        return cupSize;
    }

    public void setCupSize(String cupSize) {
        this.cupSize = cupSize;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}

也可用@Value("${content}")

不同环境启动

resources/application.yml

spring:
  profiles:
    active: dev

则启动按application-dev.yml配置启动，active: prob则按application-prob.yml启动

Controller的使用

• @Controller 要配合模版templates使用，不过现在前后端分离，后台都是Rest接口返回JSON数据了。
• @RestController：等于@Controler + @ResponseBody
• @RequestMapping
  • @PathVariable("id")
  • @RequestParam("id")

数据库

配置JPA，application.yml

spring:
  profiles:
    active: dev
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/dbgirl
    username: root
    password: 123456
  jpa:
    hibernate:
      ddl-auto: create #每次运行应用重新创建表
      #ddl-auto: update 有必要才更新
    show-sql: true

创建DAO

public interface GirlRepository extends JpaRepository<Girl,Integer> {
    public List<Girl> findByAge(Integer age);
}

使用DAO

 @Autowired
    private GirlRepository girlRepository;

    @GetMapping(value = "/girls")
    public List<Girl> girlList() {
        return girlRepository.findAll();
    }

    @PostMapping(value = "/girls")
    public Girl girlAdd(@RequestParam("cupSize") String cupSize,
                        @RequestParam("age") Integer age) {
        Girl girl = new Girl();
        girl.setCupSize(cupSize);
        girl.setAge(age);

        return girlRepository.save(girl);
    }

    @GetMapping(value = "/girls/{id}")
    public Girl girlFindOne(@PathVariable("id") Integer id) {
        return girlRepository.findOne(id);
    }

    @PutMapping(value = "/girls/{id}")
    public Girl girlUpdate(@PathVariable("id") Integer id,
                           @RequestParam("cupSize") String cupSize,
                           @RequestParam("age") Integer age) {
        Girl girl=new Girl();
        girl.setId(id);
        girl.setCupSize(cupSize);
        girl.setAge(age);
        return girlRepository.save(girl);
    }//这里注意PUT的请求参数用x-www-form-urlencoded
    
    @DeleteMapping(value = "/girls/{id}")
    public String girlDelete(@PathVariable("id") Integer id) {
        girlRepository.delete(id);
        return "Success!";
    }
    
    @GetMapping(value = "/girls/age")
    public List<Girl> girlListByAge(@PathVariable("age") Integer age){
        return girlRepository.findByAge(age);
    }

事务管理

加一个注解@Transactional

Web进阶

表单验证

现在@Entiry里的成员变量增加@Min(value = 18,message = "未成年禁止入内")，然后在Post请求里，@Valid Girl, BindingResult bindingResult

AOP

切的示例

@Aspect
@Component
public class HttpAspect {

    private final static Logger logger = LoggerFactory.getLogger(HttpAspect.class.getName());

    //切的点
    @Pointcut("execution(public * top.linxz.java.controller.GirlController.*(..))")
    public void log() {
    }

    @Before("log()")
    public void doBefore(JoinPoint joinPoint) {
        //url
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();
        logger.info("url={}", request.getRequestURL());

        //method
        logger.info("method={}", request.getMethod());

        //ip
        logger.info("ip={}", request.getRemoteAddr());

        //类方法
        logger.info("class_method={}", joinPoint.getSignature().getDeclaringTypeName() + "." + joinPoint.getSignature().getName());
        //参数
        logger.info("args={}", joinPoint.getArgs());
    }

    @After("log()")
    public void doAfter() {
        logger.info("22222222222");
    }

    @AfterReturning(returning = "object", pointcut = "log()")
    public void doAfterReturning(Object object) {
        logger.info("response{}", object);
    }
}

异常

统一处理异常

@ControllerAdvice
public class ExceptionHandle {

    @ExceptionHandler(value = Exception.class)
    @ResponseBody
    public Result handle(Exception e) {
        if (e instanceof GirlException) {
            GirlException girlException = (GirlException) e;
            return ResultUtil.error(girlException.getCode(), girlException.getMessage());
        } else {
            return ResultUtil.error(-1, "未知错误");
        }
    }

}

自定义异常

记得Spring里要继承RuntimeException，可以事务回滚。而Exception不会。

public class GirlException extends RuntimeException {
    private Integer code;

    public GirlException(Integer code, String msg) {
        super(msg);
        this.code = code;
    }

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }
}

测试

单元测试

普通单元测试

@RunWith(SpringRunner.class)
@SpringBootTest
public class GirlServiceTest {
    @Autowired
    private GirlService girlService;

    @Test
    public void findOneTest() {
        Girl girl = girlService.findOne(1);
        Assert.assertEquals(new Integer(12), girl.getAge());
    }
}

Mockc测试HTTP

@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureMockMvc
public class GirlControllerTest {

    @Autowired
    private MockMvc mvc;

    @Test
    public void girlList() throws Exception {
        mvc.perform(MockMvcRequestBuilders.get("/girls"))
                .andExpect(MockMvcResultMatchers.status().isOk());
    }
}

代码仓库：
https://github.com/linxinzhe/java-springboot-girl

关于我：

linxinzhe，全栈工程师，目前供职于某500强通信企业。人工智能，区块链爱好者。

GitHub:https://github.com/linxinzhe

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