Controller捕获异常，响应前端用户异常信息

 

前后端分离开发，后端发生异常，需要以JSON格式响应前端异常信息，前端拿到异常信息，对异常信息进行渲染，再响应给用户

不多说了，上案例~

工程搭建

这里偷懒图个方便，搭的SpringBoot的工程

0.工程结构

 

1.工程依赖

 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
</dependency>

 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
 </dependency>
 <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
 </dependency>

 

2.代码编写

。User实体

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {

    private Integer id;
    private String name;
    private String password;
}

 

。Service编写

public interface UserService {

    List<User> getUsers();
}

 

@Service
public class UserServiceImpl implements UserService {

    @Override
    public List<User> getUsers() {

        try {
            List<User> userList = new ArrayList<>();
            //这里采用伪代码进行实现，仅作为演示
            for (int i = 0; i < 10; i++) {
                userList.add(new User(i,"juwei"+i,"juwei"+i));
            }
            //手动造异常
            int i = 10/0 ;
            return userList;
        } catch (Exception e) {
            //如果发生异常，则将异常抛出，交给Controller去处理
            throw new ArithmeticException("数学运算异常");
        }

    }
}

 

。Controller编写

@RestController
public class UserController {

    @Autowired
    UserService userService;

    @GetMapping("/userList")
    public Result getAllUser() {

        try {
            List<User> users = userService.getUsers();
            return new Result(ResultCode.SUCCESS,userService);
        } catch (Exception e) {
            //捕捉调用Service进行业务逻辑处理可能抛出的异常，并将异常信息进行封装响应给前端
            e.printStackTrace();
            return new Result(ResultCode.NOT_ACCEPTABLE,e.getMessage());
        }
    }
}