Spring Boot异常处理统一解决方案详解

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.context.request.WebRequest;

import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;

// 统一错误响应结构
class ErrorResponse {
    private LocalDateTime timestamp;
    private int status;
    private String error;
    private String message;
    private String path;
    private Map<String, String> details; // 用于存放字段验证错误等

    // 构造函数、Getter和Setter...
    public ErrorResponse(HttpStatus status, String message, String path) {
        this.timestamp = LocalDateTime.now();
        this.status = status.value();
        this.error = status.getReasonPhrase();
        this.message = message;
        this.path = path;
    }

    public ErrorResponse(HttpStatus status, String message, String path, Map<String, String> details) {
        this(status, message, path);
        this.details = details;
    }

    public LocalDateTime getTimestamp() { return timestamp; }
    public int getStatus() { return status; }
    public String getError() { return error; }
    public String getMessage() { return message; }
    public String getPath() { return path; }
    public Map<String, String> getDetails() { return details; }
}

@ControllerAdvice
public class GlobalExceptionHandler {

    // 处理自定义业务异常
    @ExceptionHandler(BusinessException.class)
    public ResponseEntity<ErrorResponse> handleBusinessException(BusinessException ex, WebRequest request) {
        ErrorResponse errorResponse = new ErrorResponse(HttpStatus.BAD_REQUEST, ex.getMessage(), request.getDescription(false));
        return new ResponseEntity<>(errorResponse, HttpStatus.BAD_REQUEST);
    }

    // 处理方法参数验证失败异常（@Valid或@Validated）
    @ExceptionHandler(MethodArgumentNotValidException.class)
    public ResponseEntity<ErrorResponse> handleValidationExceptions(MethodArgumentNotValidException ex, WebRequest request) {
        Map<String, String> errors = new HashMap<>();
        ex.getBindingResult().getAllErrors().forEach((error) -> {
            String fieldName = ((FieldError) error).getField();
            String errorMessage = error.getDefaultMessage();
            errors.put(fieldName, errorMessage);
        });
        ErrorResponse errorResponse = new ErrorResponse(HttpStatus.BAD_REQUEST, "请求参数校验失败", request.getDescription(false), errors);
        return new ResponseEntity<>(errorResponse, HttpStatus.BAD_REQUEST);
    }

    // 处理所有未捕获的通用异常
    @ExceptionHandler(Exception.class)
    public ResponseEntity<ErrorResponse> handleGlobalException(Exception ex, WebRequest request) {
        // 实际项目中这里应该打印详细堆栈日志
        System.err.println("An unexpected error occurred: " + ex.getMessage());
        ex.printStackTrace(); // 仅用于开发调试，生产环境应使用日志框架
        ErrorResponse errorResponse = new ErrorResponse(
                HttpStatus.INTERNAL_SERVER_ERROR,
                "服务器内部错误，请稍后重试或联系管理员。",
                request.getDescription(false)
        );
        return new ResponseEntity<>(errorResponse, HttpStatus.INTERNAL_SERVER_ERROR);
    }
}

// 示例：自定义业务异常
class BusinessException extends RuntimeException {
    public BusinessException(String message) {
        super(message);
    }
}