SpringMVC09异常处理和类型转化器
1 public class User { 2 3 private String name; 4 private Integer age; 5 6 public String getName() { 7 return name; 8 } 9 10 public void setName(String name) { 11 this.name = name; 12 } 13 14 public Integer getAge() { 15 return age; 16 } 17 18 public void setAge(Integer age) { 19 this.age = age; 20 } 21 22 public User(String name, Integer age) { 23 super(); 24 this.name = name; 25 this.age = age; 26 } 27 28 public User() { 29 super(); 30 } 31 32 @Override 33 public String toString() { 34 return "User [name=" + name + ", age=" + age + "]"; 35 } 36 37 }
public class User {
private String name;
private Integer age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public User(String name, Integer age) {
super();
this.name = name;
this.age = age;
}
public User() {
super();
}
@Override
public String toString() {
return "User [name=" + name + ", age=" + age + "]";
}
}
对应的异常处理类

public class UserException extends Exception {
public UserException() {
super();
}
public UserException(String message) {
super(message);
}
}

public class NameException extends UserException {
public NameException() {
super();
}
public NameException(String message) {
super(message);
}
}

public class AgeException extends UserException {
public AgeException() {
super();
}
public AgeException(String message) {
super(message);
}
}

@Controller
@RequestMapping("/user")
public class MyController {
/**
* 跳转到/list
* Model:跳转list方法时 携带的数据
* @throws UserException
*/
@RequestMapping(value = "/add")
public String add(User user, Model mv) throws UserException {
System.out.println("进入了add......");
// 01.模拟异常 System.out.println(5 / 0);
// 02.模拟异常 name
if (!user.getName().equals("admin")) {
throw new NameException("用户名错误!");
}
// 03.模拟异常 age
if (user.getAge() > 50) {
throw new AgeException("年龄不合法!");
}
mv.addAttribute("name", user.getName()).addAttribute("age",
user.getAge());
return "redirect:list";
}
@RequestMapping(value = "/list")
public String list(User user) {
System.out.println("进入了list......");
System.out.println(user.getName());
System.out.println(user.getAge());
return "/success.jsp";
}
}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<!-- 配置需要扫描的包 -->
<context:component-scan base-package="cn.bdqn.controller"/>
<!-- 开启注解 -->
<mvc:annotation-driven/>
<!-- 设置异常处理 -->
<bean class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver">
<!-- 01.出现异常时 跳转的界面-->
<property name="defaultErrorView" value="/errors/error.jsp"/>
<!-- 02.给用户提示信息 -->
<property name="exceptionAttribute" value="ex"/>
<!-- 03.自定义的异常跳转界面 -->
<property name="exceptionMappings">
<props>
<prop key="cn.bdqn.exception.NameException">/errors/nameError.jsp</prop>
<prop key="cn.bdqn.exception.AgeException">/errors/ageError.jsp</prop>
</props>
</property>
</bean>
需要的界面

<body>
<form action="user/add" method="post">
<!-- 必须是User类中对应的属性名 -->
用户名:<input type="text" name="name">
年龄:<input type="text" name="age">
<button type="submit">提交</button>
</form>
</body>

<body>
<h1>错误界面</h1>
${ex.message}
</body>

<body>
<h1>name错误界面</h1>
${ex.message}
</body>

<body>
<h1>age错误界面</h1>
${ex.message}
</body>

====================自定义异常处理器===========================

/**
* 自定义的异常处理器 implements HandlerExceptionResolver
*/
public class MyExceptionResolver implements HandlerExceptionResolver {
/**
* handler:就是我们的controller
* ex:controller出现的异常信息
*/
public ModelAndView resolveException(HttpServletRequest request,
HttpServletResponse response, Object handler, Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/error.jsp"); // 其他异常处理
if (ex instanceof NameException) {
mv.setViewName("/errors/nameError.jsp");
}
if (ex instanceof AgeException) {
mv.setViewName("/errors/ageError.jsp");
}
return mv;
}
}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<!-- 配置需要扫描的包 -->
<context:component-scan base-package="cn.bdqn.controller"/>
<!-- 开启注解 -->
<mvc:annotation-driven/>
<!-- 设置自定义的异常处理器-->
<bean class="cn.bdqn.controller.MyExceptionResolver"/>
</beans>
其他代码不需要更改!测试即可!
===================使用注解的方式实现异常处理=======================
删除上个例子中xml文件 配置的自定义异常处理器

/**
*03.提取出来一个处理异常的类
*/
@Controller
public class BaseController { // 专门来处理 异常的
@ExceptionHandler
// 其他的异常
public ModelAndView defaultException(Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/error.jsp"); // 其他异常处理
return mv;
}
@ExceptionHandler(NameException.class)
// name的异常
public ModelAndView nameException(Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/nameError.jsp");
return mv;
}
@ExceptionHandler(AgeException.class)
// age的异常
public ModelAndView ageException(Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/ageError.jsp");
return mv;
}
}

@Controller
@RequestMapping("/user")
public class MyController extends BaseController {
/**
* 跳转到/list
* Model:跳转list方法时 携带的数据
* @throws UserException
*/
@RequestMapping(value = "/add")
public String add(User user, Model mv) throws UserException {
System.out.println("进入了add......");
// 01.模拟异常
// System.out.println(5 / 0);
// 02.模拟异常 name
if (!user.getName().equals("admin")) {
throw new NameException("用户名错误!");
}
// 03.模拟异常 age
if (user.getAge() > 50) {
throw new AgeException("年龄不合法!");
}
mv.addAttribute("name", user.getName()).addAttribute("age",
user.getAge());
return "redirect:list";
}
@RequestMapping(value = "/list")
public String list(User user) {
System.out.println("进入了list......");
System.out.println(user.getName());
System.out.println(user.getAge());
return "/success.jsp";
}
/**
* 01.所有的异常的都在一个方法中 处理
@ExceptionHandler
public ModelAndView resolveException(Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/error.jsp"); // 其他异常处理
if (ex instanceof NameException) {
mv.setViewName("/errors/nameError.jsp");
}
if (ex instanceof AgeException) {
mv.setViewName("/errors/ageError.jsp");
}
return mv;
}*/
/**
* 02.针对于每个异常
@ExceptionHandler
// 其他的异常
public ModelAndView defaultException(Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/error.jsp"); // 其他异常处理
return mv;
}
@ExceptionHandler(NameException.class)
// name的异常
public ModelAndView nameException(Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/nameError.jsp");
return mv;
}
@ExceptionHandler(AgeException.class)
// age的异常
public ModelAndView ageException(Exception ex) {
ModelAndView mv = new ModelAndView();
mv.addObject("ex", ex);// 保存异常信息
mv.setViewName("/errors/ageError.jsp");
return mv;
} */
}
==================类型转化器============================

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML>
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
${ex.message}
<form action="user/login" method="post">
<!-- 必须是User类中对应的属性名 -->
出生日期:<input type="text" name="birthday" value="${birthday}"> ${birthdayError}<br/>
年龄:<input type="text" name="age" value="${age}"> ${ageError}
<button type="submit">提交</button>
</form>
</body>
</html>

@Controller
@RequestMapping("/user")
public class MyController {
/**
* 登录
* Date 能自动类型转换 2015/ 02/02
*/
@RequestMapping(value = "/login")
public ModelAndView login(int age, Date birthday) {
System.out.println("进入了login......");
System.out.println(age);
System.out.println(birthday);
ModelAndView mv = new ModelAndView();
mv.addObject("age", age).addObject("birthday", birthday)
.setViewName("/success.jsp");
return mv;
}
/**
* TypeMismatchException 类型转换不了的时候 抛出的异常
* HttpServletRequest request:数据的回显
* Exception ex:给用户提示
*/
@ExceptionHandler(TypeMismatchException.class)
public ModelAndView exceptionAge(HttpServletRequest request, Exception ex) {
ModelAndView mv = new ModelAndView();
String age = request.getParameter("age");
String birthday = request.getParameter("birthday");
// 让用户看到错误的信息
String message = ex.getMessage();
if (message.contains(age)) {
mv.addObject("ageError", "年龄输入有误!");
}
if (message.contains(birthday)) {
mv.addObject("birthdayError", "日期输入有误!");
}
mv.addObject("age", age).addObject("birthday", birthday)
.addObject("ex", ex).setViewName("/index.jsp");
return mv;
}
}

/**
*
* 自定义的类型转化器
* @param <S> the source type 前台表单中肯定是string
* @param <T> the target type
*
* public interface Converter<S, T> {
*/
public class MyDateConverter implements Converter<String, Date> {
/**
* source:前台传递来的字符串
*/
public Date convert(String source) {
// 类型转化
SimpleDateFormat sdf = getDate(source);
Date parse = null;
try {
parse = sdf.parse(source);
} catch (ParseException e) {
e.printStackTrace();
}
return parse;
}
/**
* @param source 传递来的日期格式的字符串
*
*/
private SimpleDateFormat getDate(String source) {
SimpleDateFormat sdf = new SimpleDateFormat();
// 判断
if (Pattern.matches("^\\d{4}-\\d{2}-\\d{2}$", source)) {
sdf = new SimpleDateFormat("yyyy-MM-dd");
} else if (Pattern.matches("^\\d{4}/\\d{2}/\\d{2}$", source)) {
sdf = new SimpleDateFormat("yyyy/MM/dd");
} else if (Pattern.matches("^\\d{4}\\d{2}\\d{2}$", source)) {
sdf = new SimpleDateFormat("yyyyMMdd");
} else {
/**
* 都不匹配了 就让它抛出 TypeMismatchException异常
* public TypeMismatchException(Object value, Class<?> requiredType) {
* vallue 值能对应requiredType 类型 就不会出现异常
* 我们就得写一个不能转换的
*/
throw new TypeMismatchException("", Date.class);
}
return sdf;
}
}

public class User {
private String name;
private Date birthday;
private Integer age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
@Override
public String toString() {
return "User [name=" + name + ", birthday=" + birthday + ", age=" + age
+ "]";
}
public User(String name, Date birthday, Integer age) {
super();
this.name = name;
this.birthday = birthday;
this.age = age;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public User() {
super();
}
}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<!-- 配置需要扫描的包 -->
<context:component-scan base-package="cn.bdqn.controller"/>
<!-- 开启注解 -->
<mvc:annotation-driven conversion-service="conversionService"/>
<!-- 注册我们自己创建的类型转换器 -->
<bean id="myDateConverter" class="cn.bdqn.controller.MyDateConverter"/>
<!-- 创建一个类型转换器工厂 来加载我们自己创建的类型转换器 -->
<bean id="conversionService" class="org.springframework.context.support.ConversionServiceFactoryBean">
<property name="converters">
<set>
<ref bean="myDateConverter"/><!--如果需要配置多个类型转化器 只需要增加 ref节点 -->
</set>
</property>
</bean>
</beans>

<body>
<h1>webroot success页面</h1>
${birthday}<br/>
${age}
</body>
======================初始化类型绑定===================
在上面的例子中修改xml文件内容! 也就是把之前的类型转换器 删掉

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<!-- 配置需要扫描的包 -->
<context:component-scan base-package="cn.bdqn.controller"/>
<!-- 开启注解 -->
<mvc:annotation-driven/>
</beans>
修改controller中的代码

@Controller
@RequestMapping("/user")
public class MyController {
/**
* 登录
* Date 能自动类型转换 2015/ 02/02
*/
@RequestMapping(value = "/login")
public ModelAndView login(int age, Date birthday) {
System.out.println("进入了login......");
System.out.println(age);
System.out.println(birthday);
ModelAndView mv = new ModelAndView();
mv.addObject("age", age).addObject("birthday", birthday)
.setViewName("/success.jsp");
return mv;
}
/**
* 初始化参数的绑定
* binder.registerCustomEditor(Date.class, new CustomDateEditor(df, true))
* Date.class:需要转换成的类型
* new CustomDateEditor:类型编辑器
* true代表 允许日期格式为空
*/
@InitBinder
public void initBinder(WebDataBinder binder) {
DateFormat df = new SimpleDateFormat("yyyy-MM-dd"); // 只能匹配这种格式
binder.registerCustomEditor(Date.class, new CustomDateEditor(df, true));
}
}
之后可以运行 测试!
创建自己定义的类型编辑器 来完成多种日期格式的绑定

/**
*
* 自定义的类型编辑器
*/
public class MyDateEditor extends PropertiesEditor {
@Override
public void setAsText(String source) throws IllegalArgumentException {
SimpleDateFormat sdf = getDate(source);
Date parse = null;
// 类型转化
try {
parse = sdf.parse(source);
setValue(parse);
} catch (ParseException e) {
e.printStackTrace();
}
}
/**
* @param source 传递来的日期格式的字符串
*
*/
private SimpleDateFormat getDate(String source) {
SimpleDateFormat sdf = new SimpleDateFormat();
// 判断
if (Pattern.matches("^\\d{4}-\\d{2}-\\d{2}$", source)) {
sdf = new SimpleDateFormat("yyyy-MM-dd");
} else if (Pattern.matches("^\\d{4}/\\d{2}/\\d{2}$", source)) {
sdf = new SimpleDateFormat("yyyy/MM/dd");
} else if (Pattern.matches("^\\d{4}\\d{2}\\d{2}$", source)) {
sdf = new SimpleDateFormat("yyyyMMdd");
} else {
/**
* 都不匹配了 就让它抛出 TypeMismatchException异常
* public TypeMismatchException(Object value, Class<?> requiredType) {
* vallue 值能对应requiredType 类型 就不会出现异常
* 我们就得写一个不能转换的
*/
throw new TypeMismatchException("", Date.class);
}
return sdf;
}
}
修改controller中的代码

package cn.bdqn.controller;
import java.util.Date;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
@Controller
@RequestMapping("/user")
public class MyController {
/**
* 登录
* Date 能自动类型转换 2015/ 02/02
*/
@RequestMapping(value = "/login")
public ModelAndView login(int age, Date birthday) {
System.out.println("进入了login......");
System.out.println(age);
System.out.println(birthday);
ModelAndView mv = new ModelAndView();
mv.addObject("age", age).addObject("birthday", birthday)
.setViewName("/success.jsp");
return mv;
}
/**
* 初始化参数的绑定
* binder.registerCustomEditor(Date.class, new CustomDateEditor(df, true))
* Date.class:需要转换成的类型
* new CustomDateEditor:类型编辑器
* true代表 允许日期格式为空
@InitBinder
public void initBinder(WebDataBinder binder) {
DateFormat df = new SimpleDateFormat("yyyy-MM-dd"); // 只能匹配这种格式
binder.registerCustomEditor(Date.class, new CustomDateEditor(df, true));
}*/
/**
* 绑定多种日期格式
*/
@InitBinder
public void initBinder(WebDataBinder binder) {
// 使用自己定义的类型编辑器new MyDateEditor()
binder.registerCustomEditor(Date.class, new MyDateEditor());
}
}
其他代码不动 测试 即可!


浙公网安备 33010602011771号