Spring MultiActionController 使用 Command 将Form中的数据绑定
MultiActionController 可以处理多个请求，将数据绑定到Command中，可以在代码中减少类似request.getParameter("")的语句。如果能在MultiActionController的子类中使用Command就更好了。步骤如下：
第一步：配置整个环境，有4个配置配置文件：web.xml,<servlet-name>-servlet.xml,applicationContext.xml,persistence.xml，具体配置如下
1. web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"> <display-name>test-maven</display-name> <welcome-file-list> <welcome-file>/WEB-INF/page/index.jsp</welcome-file> </welcome-file-list> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:*applicationContext.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <servlet> <servlet-name>spring</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>spring</servlet-name> <url-pattern>*.htm</url-pattern> </servlet-mapping> </web-app>
2. spring-servlet.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <!-- 配置视图解析 --> <bean id="viewresolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/page/"></property> <property name="suffix" value=".jsp"></property> </bean> <bean class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> <property name="mappings"> <props> <prop key="/user.htm">userController</prop> </props> </property> </bean> <!--方法名解析器--> <bean id="methodNameResolver" class="org.springframework.web.servlet.mvc.multiaction.ParameterMethodNameResolver"> <property name="paramName"> <value>method</value> </property> </bean> <bean id="userController" class="com.test.springmvc.controller.UserFormController"> <property name="methodNameResolver"> <ref bean="methodNameResolver"/> </property> </bean> </beans>
3. applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context"
xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx"
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/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">
<bean id="oracleDataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="oracle.jdbc.OracleDriver" />
<property name="url" value="jdbc:oracle:thin:@127.0.0.1:1521:orcl" />
<property name="username" value="invoice" />
<property name="password" value="invoice" />
</bean>
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="oracleDataSource" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.TopLinkJpaVendorAdapter">
<property name="showSql" value="true" />
<property name="generateDdl" value="false" />
<property name="databasePlatform"
value="oracle.toplink.essentials.platform.database.oracle.OraclePlatform" />
</bean>
</property>
<property name="loadTimeWeaver">
<bean class="com.test.springmvc.util.MyClassLoader" />
</property>
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<!-- Dao的实现 -->
<bean id="userDao" class="com.test.springmvc.dao.impl.UserDaoImpl">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
</beans>
4. persistence.xml
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
version="1.0">
<persistence-unit name="invoice">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.test.springmvc.bean.User</class>
<!-- <properties>
<property name="hibernate.connection.driver_class" value="oracle.jdbc.driver.OracleDriver" />
<property name="hibernate.connection.url" value="jdbc:oracle:thin:@127.0.0.1:1521:orcl" />
<property name="hibernate.connection.username" value="invoice" />
<property name="hibernate.connection.password" value="invoice" />
<property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect" />
<property name="hibernate.show_sql" value="true" />
<property name="hibernate.hbm2ddl.auto" value="update" />
</properties> -->
</persistence-unit>
</persistence>
第二步：页面 index.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<%@ taglib prefix="core" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt"%>
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
<!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>welcome Page</title>
</head>
<body>
<form:form action="./user.htm?method=login" method="post">
<table align="center">
<tr>
<td><font color="red"> ${msg } </font></td>
</tr>
<tr>
<td>username:
<%-- <spring:bind path="user.userName"></spring:bind> --%>
<%-- <form:input path="userName" /></td> --%>
<input name="userName"> <%--userName 是POJO中的属性--%>
</tr>
<tr>
<td>password:
<%-- <spring:bind path="user.userPassword"></spring:bind>--%>
<%-- <form:input path="userPassword" /> --%>
<input name="userPassword"> <%--userPassword 是POJO中的属性--%>
</td>
</tr>
<tr>
<td><input id="submit" type="submit" value="submit" /></td>
<td><input id="reset" type="reset" value="reset" /></td>
</tr>
</table>
</form:form>
<br />
<form action="./user.htm?method=login" method="post">
<table>
<tr>
<td><input id="submit" type="submit" value="login" /></td>
<td><input id="reset" type="reset" value="reset" /></td>
</tr>
<tr>
<td><a href="./user.htm?method=add">add</a>
</td>
</tr>
</table>
</form>
</body>
</html>
第三步：MultiActionController子类
package com.test.springmvc.controller; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.bind.ServletRequestDataBinder; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.mvc.multiaction.MultiActionController; import com.test.springmvc.bean.User; import com.test.springmvc.service.UserService; public class UserFormController extends MultiActionController { public UserFormController() { } public ModelAndView login(HttpServletRequest req, HttpServletResponse resp) throws Exception { System.out.println("***********in login method*******************"); /** * 以下两句的作用是将 req 中的参数绑定到 POJO User中去 */ User user = (User) newCommandObject(User.class); bind(req, user); // User user = (User) command; if (user != null) { System.out.println("********user is not null**********"); System.out.println("********username is:****"+user.getUserName()); } String msg = "Well Done, this is very important task you finished"; ModelAndView modelAndView = new ModelAndView("main"); modelAndView.addObject("msg", msg); return modelAndView; } public ModelAndView add(HttpServletRequest request, HttpServletResponse response) throws Exception { System.out.println("***********in add method*******************"); return null; } }
第四步： POJO (User.java)
package com.test.springmvc.bean; import java.io.Serializable; import javax.persistence.*; /** * The persistent class for the user database table. * */ @Entity public class User implements Serializable { private static final long serialVersionUID = 1L; @Id @GeneratedValue(strategy=GenerationType.IDENTITY) @Column(name="user_id") private int userId; @Column(name="user_name") private String userName; @Column(name="user_password") private String userPassword; public User() { } public int getUserId() { return this.userId; } public void setUserId(int userId) { this.userId = userId; } public String getUserName() { return this.userName; } public void setUserName(String userName) { this.userName = userName; } public String getUserPassword() { return this.userPassword; } public void setUserPassword(String userPassword) { this.userPassword = userPassword; } }
至此，整个应用的流程已经走完。
===============================总结==============================
想要在MultiActionController中使用Command，在网上有很多，但是都不能work。经过这次配置，总结起来，关键的是两点：
1. 在Page中form中的数据name为POJO的属性 (文中为User的属性)
2. 在MultiActionController的子类中，
首先 使用newCommandObject(Class)方法创建Command对象
然后 调用MultiActionController的bind(request,Command)方法，将request中的数据绑定到command中