1. 自己定义一个异常类: UserException.java
public class UserException extends RuntimeException {
private static final long serialVersionUID = 1L;
public UserException() {
super();
}
public UserException(String message, Throwable cause) {
super(message, cause);
}
public UserException(String message) {
super(message);
}
public UserException(Throwable cause) {
super(cause);
}
}2. 使用用户登录的样例: UserController.java
假定username不存在或用户password错误系统会抛出异常, 并跳到error.jsp页面
@Controller
@RequestMapping("/user")
public class UserController {
// 使用map模拟数据库
private Map<String, User> userMap = new HashMap<String, User>();
public UserController() {
userMap.put("zhangsan", new User("zhangsan", "123"));
userMap.put("lishimin", new User("lishimin", "456"));
}
// 用户登录之异常处理
// 訪问方法: http://localhost/springmvc_user/login.jsp
@RequestMapping(value="/login", method=RequestMethod.POST)
public String login(String username, String password, HttpSession session) {
if(!userMap.containsKey(username)) {
throw new UserException("用户名不存在");
}
User user = userMap.get(username);
if(!user.getPassword().equals(password)) {
throw new UserException("用户密码不对");
}
session.setAttribute("loginUser", user);
return "redirect:/user/users";
}
/**
* 局部异常处理(仅仅能处理这个控制器中的异常)
*/
@ExceptionHandler(value={UserException.class})
public String handlerException(UserException e,HttpServletRequest request) {
request.setAttribute("exception",e);
return "exception/error";
}
}3. 配置全局异常处理: user-servlet.xml
<!-- 全局异常处理 --> <bean id="exceptionResolver" class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver"> <property name="exceptionMappings"> <props> <prop key="com.zdp.exception.UserException">exception/error</prop> </props> </property> </bean>
4. 错误信息页面: error.jsp
<%@ 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>错误页面</title>
</head>
<body>
发现错误: ${exception.message}
</body>
</html>