SpringBoot 统一异常管理

言曌 2018年03月24日16:42:02 6 3490 views

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通常，SpringBoot 默认的异常页面是这样的，用户根本看不懂，系统遇到 Bug 的话，也不知道跟管理员怎么反馈。

而自定义的异常页面是这样的，意思明朗很多。

通过配置全局异常管理，我们不仅可以美化页面的显示，自定义错误的信息。还可以捕获很多我们遇到的错误，并将它们写入日志中。虽然很多提交表单的异常可以通过前台 js 避免，但是万一用户禁用 js 呢？为了数据安全，我们在后台还是要加一层安全保护。

现在就开始吧！

代码如下

1、这是一个统一异常处理类

GlobalExceptionHandler.java

package com.liuyanzhao.forum.exception;
import org.hibernate.service.spi.ServiceException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.ui.Model;
import org.springframework.validation.BindException;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.web.HttpMediaTypeNotSupportedException;
import org.springframework.web.HttpRequestMethodNotSupportedException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.MissingServletRequestParameterException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.servlet.NoHandlerFoundException;
import javax.validation.ConstraintViolation;
import javax.validation.ConstraintViolationException;
import javax.validation.ValidationException;
import java.util.Set;
/**
* @author 言曌
* @date 2018/3/20 下午12:57
*/
@ControllerAdvice
public class GlobalExceptionHandler {
// 日志记录工具
private static final Logger logger = LoggerFactory.getLogger(GlobalExceptionHandler.class);
//错误显示页面,即 /public/error/error.html 文件
public static final String viewName = "/error/error";
/**
* 400 - Bad Request
*/
@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(MissingServletRequestParameterException.class)
public String handleMissingServletRequestParameterException(MissingServletRequestParameterException e, Model model) {
logger.error("缺少请求参数", e);
String message = "【缺少请求参数】" + e.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 400);
return viewName;
}
/**
* 400 - Bad Request
*/
@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(HttpMessageNotReadableException.class)
public String handleHttpMessageNotReadableException(HttpMessageNotReadableException e, Model model) {
logger.error("参数解析失败", e);
String message = "【参数解析失败】" + e.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 400);
return viewName;
}
/**
* 400 - Bad Request
*/
@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(MethodArgumentNotValidException.class)
public String handleMethodArgumentNotValidException(MethodArgumentNotValidException e, Model model) {
logger.error("参数验证失败", e);
BindingResult result = e.getBindingResult();
FieldError error = result.getFieldError();
String field = error.getField();
String code = error.getDefaultMessage();
String message = "【参数验证失败】" + String.format("%s:%s", field, code);
model.addAttribute("message", message);
model.addAttribute("code", 400);
return viewName;
}
/**
* 400 - Bad Request
*/
@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(BindException.class)
public String handleBindException(BindException e, Model model) {
logger.error("参数绑定失败", e);
BindingResult result = e.getBindingResult();
FieldError error = result.getFieldError();
String field = error.getField();
String code = error.getDefaultMessage();
String message = "【参数绑定失败】" + String.format("%s:%s", field, code);
model.addAttribute("message", message);
model.addAttribute("code", 400);
return viewName;
}
/**
* 400 - Bad Request
*/
@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(ConstraintViolationException.class)
public String handleServiceException(ConstraintViolationException e, Model model) {
logger.error("参数验证失败", e);
Set<ConstraintViolation<?>> violations = e.getConstraintViolations();
ConstraintViolation<?> violation = violations.iterator().next();
String message = "【参数验证失败】" + violation.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 400);
return viewName;
}
/**
* 400 - Bad Request
*/
@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(ValidationException.class)
public String handleValidationException(ValidationException e, Model model) {
logger.error("参数验证失败", e);
String message = "【参数验证失败】" + e.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 400);
return viewName;
}
/**
* 404 - Not Found
*/
@ResponseStatus(HttpStatus.NOT_FOUND)
@ExceptionHandler(NoHandlerFoundException.class)
public String noHandlerFoundException(NoHandlerFoundException e, Model model) {
logger.error("Not Found", e);
String message = "【页面不存在】" + e.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 404);
System.out.println("404404错误");
return viewName;
}
/**
* 405 - Method Not Allowed
*/
@ResponseStatus(HttpStatus.METHOD_NOT_ALLOWED)
@ExceptionHandler(HttpRequestMethodNotSupportedException.class)
public String handleHttpRequestMethodNotSupportedException(HttpRequestMethodNotSupportedException e, Model model) {
logger.error("不支持当前请求方法", e);
String message = "【不支持当前请求方法】" + e.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 405);
return viewName;
}
/**
* 415 - Unsupported Media Type
*/
@ResponseStatus(HttpStatus.UNSUPPORTED_MEDIA_TYPE)
@ExceptionHandler(HttpMediaTypeNotSupportedException.class)
public String handleHttpMediaTypeNotSupportedException(HttpMediaTypeNotSupportedException e, Model model) {
logger.error("不支持当前媒体类型", e);
String message = "【不支持当前媒体类型】" + e.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 415);
return viewName;
}
/**
* 业务层需要自己声明异常的情况
*/
@ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
@ExceptionHandler(ServiceException.class)
public String handleServiceException(ServiceException e, Model model) {
logger.error("业务逻辑异常", e);
String message = "【业务逻辑异常】" + e.getMessage();
model.addAttribute("message", message);
return viewName;
}
/**
* 获取其它异常。包括500
*
* @param e
* @return
* @throws Exception
*/
@ExceptionHandler(value = Exception.class)
public String defaultErrorHandler(Exception e, Model model) {
logger.error("Exception", e);
String message = e.getMessage();
model.addAttribute("message", message);
model.addAttribute("code", 500);
return viewName;
}
}

注意修改 37 行的错误页面地址

不知道为什么 404 页面无法捕获

2、这是一个我们自定义的异常，通常我们可以主动抛它，当然，也可以直接抛 Exception

CustomException.java

package com.liuyanzhao.forum.exception;
/**
* 自定义异常
* @author 言曌
* @date 2018/3/20 下午12:50
*/
public class CustomException extends RuntimeException {
/** serialVersionUID */
private static final long serialVersionUID = 6417641452178955756L;
public CustomException() {
super();
}
public CustomException(String message) {
super(message);
}
public CustomException(Throwable cause) {
super(cause);
}
public CustomException(String message, Throwable cause) {
super(message, cause);
}
}

3、在 template 或者资源根目录下新建 error 文件夹

error.html

<div class="error-page">
${code=} <span th:text="${code}"></span>
<h2 class="headline text-red" th:text="${code}"></h2>
<div class="error-content" style="margin-top: 120px;">
<h3><i class="fa fa-warning text-red"></i> 天哪! 好像遇到了错误.</h3>
<p style="font-size: 1.2em;">
错误信息： <span th:text="${message}" class="text text-danger"></span>
</p>
<p><a href="javascript:history.go(-1)">返回上一页</a></p>
<form class="search-form">
<div class="input-group">
<input type="text" name="search" class="form-control" placeholder="Search">
<div class="input-group-btn">
<button type="submit" name="submit" class="btn btn-danger btn-flat"><i class="fa fa-search"></i>
</button>
</div>
</div>
</form>
</div>
</div>

因为 404 页面好像无法捕获，那么我们可以再新建一个 404.html ，内容和上面差不多，改一下错误码为 404 即可。

4、为了演示使用，这里是 UserServiceImpl.java 里的一个添加新用户的方法

@Transactional(rollbackFor = Exception.class)
@Override
public void saveUser(User user) {
String username = user.getUsername();
String nickname = user.getNickname();
String password = user.getPassword();
String email = user.getEmail();
//1、非空判断
if (username == null || nickname == null || password == null || email == null) {
throw new CustomException("存在必填字段为空");
} else {
if (username.trim() == "" || password.trim() == "") {
throw new CustomException("存在必填字段为空字符串");
} else if(password.trim().length() < 6) {
throw new CustomException("密码长度小于6位");
}
}
//2、判断用户名是否合法
if (username != null && username != "") {
User user2 = userRepository.findByUsername(username);
//2.1用户名已存在，不可以注册
if (user2 != null) {
throw new CustomException("用户名 " + username + " 已被使用");
}
}
//3、判断Email是否合法
if (email != null && email != "") {
User user3 = userRepository.findByEmail(email);
//1.1用户名已存在，不可以注册
if (user3 != null) {
throw new CustomException("Email " + email + "已被使用");
}
}
//4、处理其他字段
user.setCreateTime(System.currentTimeMillis());
user.setEncodePassword(user.getPassword()); // 加密密码
user.setIsBanned("N");//正常状态
user.setNumberVoteUp(0);//票数
user.setAvatar(AvatarUtil.getGravatar(email));//头像
if (user.getNickname() == null) {
user.setNickname(username);//默认昵称是用户名
}
userRepository.save(user);
}