自定义RuntimeException抛出后，为何返回结果包含堆栈跟踪信息？

在Spring Boot项目中实现了自定义异常InvalidEntryException（继承自RuntimeException），在EmployeeServiceImpl的updateEmployeeDto方法中，当传入无效员工ID时抛出该异常。目前异常消息已正常记录，但Postman返回结果中同时包含堆栈跟踪（trace）信息，相关代码及返回结果如下：

抛出异常的Service类代码 #

@Service
public class EmployeeServiceImpl implements EmployeeService {
    // 输入无效员工ID时程序应抛出错误
    public EmployeeDTO updateEmployeeDto(EmployeeDTO employeeDTO, Long employeeId){
        Optional<Employees> employeeWithId = Optional.ofNullable(employeesRepo.findByEmployeeId(employeeId));
        if(!employeeWithId.isEmpty()){
            Employees employee=employeeWithId.get();
        }
        else{
            throw new InvalidEntryException("Entered employee id  was not found");
        }
    }
}

自定义异常类代码 #

public class InvalidEntryException extends RuntimeException{
    public InvalidEntryException(String message){
        super(message);
    }
}

Postman返回结果 #

{
    "timestamp": "2022-12-19T05:33:03.854+00:00",
    "status": 500,
    "error": "Internal Server Error",
    "trace": "com.assetmanagementsystems.ams.exception.InvalidEntryException: Entered employee id  was not found\r\n\tat com.assetmanagementsystems.ams.service.serviceImpl.EmployeeServiceImpl.getEmployeeById(EmployeeServiceImpl.java:64)\r\n\tat com.assetmanagementsystems.ams.controller.EmployeeController.retrieveEmpById(EmployeeController.java:60)java.base/java.lang.Thread.run(Thread.java:833)\r\n",
    "message": "Entered employee id  was not found",
    "path": "/employees/employee/22"
}

这是Spring Boot默认异常处理机制的行为：在开发环境（默认启动环境）下，为方便开发者调试，DefaultErrorAttributes会返回完整的错误详情，其中就包含堆栈跟踪信息；而生产环境下默认不会返回trace内容。

方法1：通过配置控制返回策略 #

直接修改配置文件，全局控制是否返回堆栈跟踪，适合不需要自定义响应结构的场景：

application.properties配置 #

# 无论环境，永远不返回堆栈跟踪
server.error.include-stacktrace=never
# 或者保持默认逻辑：仅在请求参数带trace时返回，生产环境默认不返回
# server.error.include-stacktrace=on_trace_param

application.yml配置 #

server:
  error:
    include-stacktrace: never

方法2：自定义全局异常处理器 #

通过@RestControllerAdvice和@ExceptionHandler捕获自定义异常，返回完全自定义的响应体，彻底控制返回内容，同时还能修正HTTP状态码（比如把500改为更合理的404）：

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.context.request.ServletWebRequest;
import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;

@RestControllerAdvice
public class GlobalExceptionHandler {

    @ExceptionHandler(InvalidEntryException.class)
    public ResponseEntity<Map<String, Object>> handleInvalidEntryException(InvalidEntryException ex, ServletWebRequest request) {
        Map<String, Object> errorResponse = new HashMap<>();
        errorResponse.put("timestamp", LocalDateTime.now().toString());
        errorResponse.put("status", HttpStatus.NOT_FOUND.value());
        errorResponse.put("error", "Not Found");
        errorResponse.put("message", ex.getMessage());
        errorResponse.put("path", request.getRequest().getRequestURI());

        return new ResponseEntity<>(errorResponse, HttpStatus.NOT_FOUND);
    }
}

配置后，抛出InvalidEntryException时，Postman会返回你定义的响应结构，不会包含堆栈跟踪信息。

内容的提问来源于stack exchange，提问作者Vibhanshu Jha