作者: BNDong\
链接: https://www.cnblogs.com/bndon...
前言
在启动应用时会发现在控制台打印的日志中出现了两个路径为 {[/error]} 的访问地址,当系统中发送异常错误时,Spring Boot 会根据请求方式分别跳转到以 JSON 格式或以界面显示的 /error 地址中显示错误信息。
2018-12-18 09:36:24.627 INFO 19040 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" ...
2018-12-18 09:36:24.632 INFO 19040 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" ...
Spring Boot 基础就不介绍了,推荐下这个实战教程:
https://github.com/javastacks...
默认异常处理
使用 AJAX 方式请求时返回的 JSON 格式错误信息。
{
"timestamp": "2018-12-18T01:50:51.196+0000",
"status": 404,
"error": "Not Found",
"message": "No handler found for GET /err404",
"path": "/err404"
}
使用浏览器请求时返回的错误信息界面。
自定义异常处理
引入依赖
com.alibaba
fastjson
1.2.54
org.springframework.boot
spring-boot-starter-freemarker
fastjson 是 JSON 序列化依赖, spring-boot-starter-freemarker 是一个模板引擎,用于我们设置错误输出模板。
增加配置
# 出现错误时, 直接抛出异常(便于异常统一处理,否则捕获不到404)
spring.mvc.throw-exception-if-no-handler-found=true
# 不要为工程中的资源文件建立映射
spring.resources.add-mappings=false
spring:
# 出现错误时, 直接抛出异常(便于异常统一处理,否则捕获不到404)
mvc:
throw-exception-if-no-handler-found: true
# 不要为工程中的资源文件建立映射
resources:
add-mappings: false
Spring Boot 基础就不介绍了,推荐下这个实战教程:
https://github.com/javastacks...
新建错误信息实体
/**
* 信息实体
*/
public class ExceptionEntity implements Serializable {
private static final long serialVersionUID = 1L;
private String message;
private int code;
private String error;
private String path;
@JSONField(format = "yyyy-MM-dd hh:mm:ss")
private Date timestamp = new Date();
public static long getSerialVersionUID() {
return serialVersionUID;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public int getCode() {
return code;
}
public void setCode(int code) {
this.code = code;
}
public String getError() {
return error;
}
public void setError(String error) {
this.error = error;
}
public String getPath() {
return path;
}
public void setPath(String path) {
this.path = path;
}
public Date getTimestamp() {
return timestamp;
}
public void setTimestamp(Date timestamp) {
this.timestamp = timestamp;
}
}
新建自定义异常
/**
* 自定义异常
*/
public class BasicException extends RuntimeException {
private static final long serialVersionUID = 1L;
private int code = 0;
public BasicException(int code, String message) {
super(message);
this.code = code;
}
public int getCode() {
return this.code;
}
}
/**
* 业务异常
*/
public class BusinessException extends BasicException {
private static final long serialVersionUID = 1L;
public BusinessException(int code, String message) {
super(code, message);
}
}
BasicException 继承了 RuntimeException ,并在原有的 Message 基础上增加了错误码 code 的内容。而 BusinessException 则是在业务中具体使用的自定义异常类,起到了对不同的异常信息进行分类的作用。
新建 error.ftl 模板文件
位置:/src/main/resources/templates/ 用于显示错误信息
Exception Datas
Code
${(exception.code)!}
Time
${(exception.timestamp?datetime)!}
Path
${(exception.path)!}
Exception
${(exception.error)!}
Message
${(exception.message)!}
编写全局异常控制类
/**
* 全局异常控制类
*/
@ControllerAdvice
public class GlobalExceptionHandler {
/**
* 404异常处理
*/
@ExceptionHandler(value = NoHandlerFoundException.class)
@ResponseStatus(HttpStatus.NOT_FOUND)
public ModelAndView errorHandler(HttpServletRequest request, NoHandlerFoundException exception, HttpServletResponse response) {
return commonHandler(request, response,
exception.getClass().getSimpleName(),
HttpStatus.NOT_FOUND.value(),
exception.getMessage());
}
/**
* 405异常处理
*/
@ExceptionHandler(HttpRequestMethodNotSupportedException.class)
public ModelAndView errorHandler(HttpServletRequest request, HttpRequestMethodNotSupportedException exception, HttpServletResponse response) {
return commonHandler(request, response,
exception.getClass().getSimpleName(),
HttpStatus.METHOD_NOT_ALLOWED.value(),
exception.getMessage());
}
/**
* 415异常处理
*/
@ExceptionHandler(HttpMediaTypeNotSupportedException.class)
public ModelAndView errorHandler(HttpServletRequest request, HttpMediaTypeNotSupportedException exception, HttpServletResponse response) {
return commonHandler(request, response,
exception.getClass().getSimpleName(),
HttpStatus.UNSUPPORTED_MEDIA_TYPE.value(),
exception.getMessage());
}
/**
* 500异常处理
*/
@ExceptionHandler(value = Exception.class)
public ModelAndView errorHandler (HttpServletRequest request, Exception exception, HttpServletResponse response) {
return commonHandler(request, response,
exception.getClass().getSimpleName(),
HttpStatus.INTERNAL_SERVER_ERROR.value(),
exception.getMessage());
}
/**
* 业务异常处理
*/
@ExceptionHandler(value = BasicException.class)
private ModelAndView errorHandler (HttpServletRequest request, BasicException exception, HttpServletResponse response) {
return commonHandler(request, response,
exception.getClass().getSimpleName(),
exception.getCode(),
exception.getMessage());
}
/**
* 表单验证异常处理
*/
@ExceptionHandler(value = BindException.class)
@ResponseBody
public ExceptionEntity validExceptionHandler(BindException exception, HttpServletRequest request, HttpServletResponse response) {
List fieldErrors = exception.getBindingResult().getFieldErrors();
Map errors = new HashMap<>();
for (FieldError error:fieldErrors) {
errors.put(error.getField(), error.getDefaultMessage());
}
ExceptionEntity entity = new ExceptionEntity();
entity.setMessage(JSON.toJSONString(errors));
entity.setPath(request.getRequestURI());
entity.setCode(HttpStatus.INTERNAL_SERVER_ERROR.value());
entity.setError(exception.getClass().getSimpleName());
response.setStatus(HttpStatus.INTERNAL_SERVER_ERROR.value());
return entity;
}
/**
* 异常处理数据处理
*/
private ModelAndView commonHandler (HttpServletRequest request, HttpServletResponse response,
String error, int httpCode, String message) {
ExceptionEntity entity = new ExceptionEntity();
entity.setPath(request.getRequestURI());
entity.setError(error);
entity.setCode(httpCode);
entity.setMessage(message);
return determineOutput(request, response, entity);
}
/**
* 异常输出处理
*/
private ModelAndView determineOutput(HttpServletRequest request, HttpServletResponse response, ExceptionEntity entity) {
if (!(
request.getHeader("accept").contains("application/json")
|| (request.getHeader("X-Requested-With") != null && request.getHeader("X-Requested-With").contains("XMLHttpRequest"))
)) {
ModelAndView modelAndView = new ModelAndView("error");
modelAndView.addObject("exception", entity);
return modelAndView;
} else {
response.setStatus(HttpStatus.INTERNAL_SERVER_ERROR.value());
response.setCharacterEncoding("UTF8");
response.setHeader("Content-Type", "application/json");
try {
response.getWriter().write(ResultJsonTools.build(
ResponseCodeConstant.SYSTEM_ERROR,
ResponseMessageConstant.APP_EXCEPTION,
JSONObject.parseObject(JSON.toJSONString(entity))
));
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
}
@ControllerAdvice
作用于类上,用于标识该类用于处理全局异常。
@ExceptionHandler
作用于方法上,用于对拦截的异常类型进行处理。value 属性用于指定具体的拦截异常类型,如果有多个 ExceptionHandler 存在,则需要指定不同的 value 类型,由于异常类拥有继承关系,所以 ExceptionHandler 会首先执行在继承树中靠前的异常类型。
BindException
该异常来自于表单验证框架 Hibernate validation,当字段验证未通过时会抛出此异常。
编写测试 Controller
@RestController
public class TestController {
@RequestMapping(value = "err")
public void error(){
throw new BusinessException(400, "业务异常错误信息");
}
@RequestMapping(value = "err2")
public void error2(){
throw new NullPointerException("手动抛出异常信息");
}
@RequestMapping(value = "err3")
public int error3(){
int a = 10 / 0;
return a;
}
}
使用 AJAX 方式请求时返回的 JSON 格式错误信息。
# /err
{
"msg": "应用程序异常",
"code": -1,
"status_code": 0,
"data": {
"path": "/err",
"code": 400,
"error": "BusinessException",
"message": "业务异常错误信息",
"timestamp": "2018-12-18 11:09:00"
}
}
# /err2
{
"msg": "应用程序异常",
"code": -1,
"status_code": 0,
"data": {
"path": "/err2",
"code": 500,
"error": "NullPointerException",
"message": "手动抛出异常信息",
"timestamp": "2018-12-18 11:15:15"
}
}
# /err3
{
"msg": "应用程序异常",
"code": -1,
"status_code": 0,
"data": {
"path": "/err3",
"code": 500,
"error": "ArithmeticException",
"message": "/ by zero",
"timestamp": "2018-12-18 11:15:46"
}
}
# /err404
{
"msg": "应用程序异常",
"code": -1,
"status_code": 0,
"data": {
"path": "/err404",
"code": 404,
"error": "NoHandlerFoundException",
"message": "No handler found for GET /err404",
"timestamp": "2018-12-18 11:16:11"
}
}
使用浏览器请求时返回的错误信息界面。
示例代码:https://github.com/BNDong/spr...
参考资料:
- 《微服务 分布式架构开发实战》 龚鹏 著
- https://www.jianshu.com/p/1a4...
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