全局异常处理

案例一：

自定义异常

public class StudentException extends RuntimeException {

    private Integer code;
    private String msg;

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

    /**
     * 这里需要重写 getMessage方法，否则会报控指针错误
     * getMessage：输出异常类的报错信息
     *
     * @return
     */
    @Override
    public String getMessage() {
        return this.getMsg();
    }

    public String getMsg() {
        return msg;
    }

    public Integer getCode() {
        return code;
    }
}

异常信息类枚举类
指定错误规则，方便区分错误信息。

public enum ExecptionStatusEnum {

    STUDENT_ERROR_EXECPTION(01, "学号错误"), STUDENT_UNORDER_EXECPTION(02, "学号不存在");


    private Integer code;
    private String msg;

    ExecptionStatusEnum(Integer code, String msg) {
        this.code = code;
        this.msg = msg;
    }

    public Integer getCode() {
        return code;
    }

    public String getMsg() {
        return msg;
    }
}

全局异常处理

自定义返回类

public class Result extends HashMap<String, Object> {
    /**
     * 状态码
     */
    public static final String CODE_TAG = "code";

    /**
     * 返回内容
     */
    public static final String MSG_TAG = "msg";

    /**
     * 数据对象
     */
    public static final String DATA_TAG = "data";

    public Result() {

    }

    public Result(Integer code, String msg, Object data) {
        super.put(CODE_TAG, code);
        super.put(MSG_TAG, msg);
        if (data != null) {
            super.put(DATA_TAG, data);
        }
    }

    public static Result ok() {
        return Result.ok(200, "操作成功");
    }

    public static Result ok(Integer code, String msg) {
        return new Result(code, msg, null);
    }


    public static Result error() {
        return Result.ok(500, "系统错误");
    }

    public static Result error(Integer code, String msg) {
        return new Result(code, msg, null);
    }

    public static Result ok(Object data) {
        return new Result(200, "操作成功", data);
    }
}

全局异常处理类

@RestControllerAdvice
public class GlobalExceptionHandler {

    /**
     * 自定义异常类
     */
    @ExceptionHandler(StudentException.class)
    public Result handleStudentException(StudentException e) {
        return Result.error(e.getCode(), e.getMsg());
    }

    /**
     * 其他异常
     */
    @ExceptionHandler(Exception.class)
    public Result handleException(Exception e) {
        return Result.error(HttpStatus.INTERNAL_SERVER_ERROR.value(), e.getMessage());
    }

}

Controller层

@RestController
public class StudentController {

    @GetMapping("/student/{id}")
    public Result test(@PathVariable("id") Long id) {
        if (id == 1) {
            // 抛出异常：学生错误
            throw new StudentException(StudentExecptionStatusEnum.STUDENT_ERROR_EXECPTION.getCode(),
                    StudentExecptionStatusEnum.STUDENT_ERROR_EXECPTION.getMsg());
        } else if (id == 2) {
            // 抛出异常：学生不存在
            throw new StudentException(StudentExecptionStatusEnum.STUDENT_UNORDER_EXECPTION.getCode(),
                    StudentExecptionStatusEnum.STUDENT_ERROR_EXECPTION.getMsg());
        }
        // 返回 学生信息
        return Result.ok(new Student(4, "zqsl1234"));
    }
}

案例二：

自定义异常类

public class MyException extends RuntimeException{
 
    public MyException(){
        super();
    }
 
    public MyException(String message){
        super(message);
    }
 
    public MyException(Throwable cause){
        super(cause);
    }
 
    public MyException(String message,Throwable cause){
        super(message,cause);
    }
}

全局异常处理类

@RestControllerAdvice
public class GlobalExceptionHandler {

    /**
     * 自定义异常类
     */
    @ExceptionHandler(MyException.class)
    public ResponseEntity<String> handleMyException(MyException e) {
        return new ResponseEntity<>(e.getMessage(), HttpStatus.INTERNAL_SERVER_ERROR);
    }

    /**
     * 其他异常
     */
    @ExceptionHandler(Exception.class)
    public Result handleException(Exception e) {
        return new ResponseEntity<>(e.getMessage(), HttpStatus.INTERNAL_SERVER_ERROR);
    }

}

测试

public class Test {
    public void test(){
        throw  new MyException("我是自定义报错信息");
    }
 
    public static void main(String[] args){
        Test test = new Test();
        test.test();
    }
}