Springmvc自定义异常处理器实现流程解析
时间：2020-11-20 18:33:57 | 栏目：JAVA代码 | 点击：次
当dispatchServlet接收到controller抛出的异常时，会将异常交由 HandlerExceptionResolver
异常处理器处理！我们可以创建自定义异常处理器实现该接口来处理自定义异常
1） 自定义异常类
public class MyException extends Exception {
// 异常信息
private String message;
public MyException() {
super();
}
public MyException(String message) {
super();
this.message = message;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
2）自定义异常处理器
public class CustomHandleException implements HandlerExceptionResolver {
@Override
public ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, Object handler,
Exception exception) {
// 定义异常信息
String msg;
// 判断异常类型
if (exception instanceof MyException) {
// 如果是自定义异常，读取异常信息
msg = exception.getMessage();
} else {
// 如果是运行时异常，则取错误堆栈，从堆栈中获取异常信息
Writer out = new StringWriter();
PrintWriter s = new PrintWriter(out);
exception.printStackTrace(s);
msg = out.toString();
}
// 把错误信息发给相关人员,邮件,短信等方式
// TODO
// 返回错误页面，给用户友好页面显示错误信息
ModelAndView modelAndView = new ModelAndView();
modelAndView.addObject("msg", msg);
modelAndView.setViewName("error");
return modelAndView;
}
}
3）在springmvc.xml中配置异常处理器
<!-- 配置全局异常处理器 --> <bean id="customHandleException" class="cn.itcast.ssm.exception.CustomHandleException"/>
4）定制错误页面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<h1>系统发生异常了！</h1>
<br />
<h1>异常信息</h1>
<br />
<h2>${msg }</h2>
</body>
</html>
5）测试异常处理
@RequestMapping(value = "/item/itemlist.action")
public ModelAndView itemList() throws MyException{
List<Items> list = itemService.selectItemsList();
if(true){
throw new MyException("商品列表不能为空！！");
}
ModelAndView mav = new ModelAndView();
mav.addObject("itemList", list);
mav.setViewName("itemList");
return mav;
}
