Global Exception Handling in Spring Boot: Techniques and Code Examples

In daily project development, exceptions are common; handling them efficiently improves debugging and code readability.

SpringBoot already provides basic exception handling, but developers often need a unified approach.

Global Exception Handling Method 1

Using @ControllerAdvice to enable global exception handling and @ExceptionHandler to define methods for specific exception types.

1.1 Custom Global Exception Class

/**
 * @description 自定义异常处理
 * @author DT
 * @version v1.0 */
@ControllerAdvice
public class MyExceptionHandler {
    @ExceptionHandler(value = Exception.class)
    @ResponseBody
    public String exceptionHandler(Exception e) {
        System.out.println("全局异常捕获>>>:" + e);
        return "全局异常捕获,错误原因>>>" + e.getMessage();
    }
}

1.2 Manually Throwing Exceptions

@GetMapping("/getById/{userId}")
public CommonResult
getById(@PathVariable Integer userId) {
    // 手动抛出异常
    int a = 10/0;
    return CommonResult.success(userService.getById(userId));
}

These approaches expose raw exception messages, which may be unfriendly to users.

Global Exception Handling Method 2

2.1 Define Base Error Interface

public interface BaseErrorInfoInterface {
    String getResultCode();
    String getResultMsg();
}

2.2 Define Enum for Error Codes

public enum ExceptionEnum implements BaseErrorInfoInterface {
    SUCCESS("2000","成功!"),
    BODY_NOT_MATCH("4000","请求的数据格式不符!"),
    SIGNATURE_NOT_MATCH("4001","请求的数字签名不匹配!"),
    NOT_FOUND("4004","未找到该资源!"),
    INTERNAL_SERVER_ERROR("5000","服务器内部错误!"),
    SERVER_BUSY("5003","服务器正忙，请稍后再试!"),
    PARAMS_NOT_CONVERT("4002","类型转换不对!");
    // getters omitted
}

2.3 Custom Business Exception

public class BizException extends RuntimeException {
    private String errorCode;
    private String errorMsg;
    // constructors and getters/setters
}

2.4 Standard Response Wrapper

public class ResultResponse {
    private String code;
    private String message;
    private Object result;
    // static factory methods success() and error()
}

2.5 Global Exception Handler Implementation

@ControllerAdvice
public class GlobalExceptionHandler {
    private static final Logger logger = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    @ExceptionHandler(value = BizException.class)
    @ResponseBody
    public ResultResponse bizExceptionHandler(HttpServletRequest req, BizException e) {
        logger.error("发生业务异常！原因是：{}", e.getErrorMsg());
        return ResultResponse.error(e.getErrorCode(), e.getErrorMsg());
    }

    @ExceptionHandler(value = NullPointerException.class)
    @ResponseBody
    public ResultResponse exceptionHandler(HttpServletRequest req, NullPointerException e) {
        logger.error("发生空指针异常！原因是:", e);
        return ResultResponse.error(ExceptionEnum.BODY_NOT_MATCH);
    }

    @ExceptionHandler(value = Exception.class)
    @ResponseBody
    public ResultResponse exceptionHandler(HttpServletRequest req, Exception e) {
        logger.error("未知异常！原因是:", e);
        return ResultResponse.error(ExceptionEnum.INTERNAL_SERVER_ERROR);
    }
}

2.6 Test Controllers

@PostMapping("/add")
public boolean add(@RequestBody User user) {
    if (user.getName() == null) {
        throw new BizException("-1","用户姓名不能为空！");
    }
    return true;
}

@PutMapping("/update")
public boolean update(@RequestBody User user) {
    String str = null;
    str.equals("111"); // triggers NullPointerException
    return true;
}

@DeleteMapping("/delete")
public boolean delete(@RequestBody User user) {
    Integer.parseInt("abc123"); // triggers NumberFormatException
    return true;
}

2.7 Handling NumberFormatException

@ExceptionHandler(value = NumberFormatException.class)
@ResponseBody
public ResultResponse exceptionHandler(HttpServletRequest req, NumberFormatException e) {
    logger.error("发生类型转换异常！原因是:", e);
    return ResultResponse.error(ExceptionEnum.PARAMS_NOT_CONVERT);
}

By centralizing exception handling, code duplication is reduced, maintenance becomes easier, and developers can quickly locate bugs, greatly improving development efficiency.