JavaWeb -- Struts2 模型驱动
1. 模型驱动
示例：
注册表单reg.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"%> <%@taglib uri="/struts-tags" prefix="s"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>reg.jsp</title> </head> <body> <s:actionerror/> <s:form namespace="/md" action="MdAction_reg" method="post" theme="xhtml" validate="true"> <s:textfield name="name" label="UserName" /> <s:textfield name="age" label="UserAge" /> <s:submit /> </s:form> </body> </html>
用户显示list页面 userList.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"%> <%@taglib uri="/struts-tags" prefix="s"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>reg.jsp</title> </head> <body> <table border="1"> <tr> <td>id</td><td>name</td><td>age</td><td>edit</td> </tr> <s:iterator value="userList"> <tr> <td><s:property value="id" /></td> <td><s:property value="name" /></td> <td><s:property value="age" /></td> <td> <a href='<s:url action="MdAction_edit" namespace="/md"><s:param name="uid" value="id" /></s:url>'>edit</a> </td> </tr> </s:iterator> </table> </body> </html>
处理action，模型驱动需要实现ModelDriven 接口，实现Preparable 接口，在modelDriven拦截器之前先运行 prepare拦截器。
package cn.itcast.struts2.modeldriven;
import java.util.ArrayList;
import java.util.List;
import org.apache.struts2.ServletActionContext;
import org.apache.struts2.interceptor.validation.SkipValidation;
import cn.itcast.struts2.model.User;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;
import com.opensymphony.xwork2.Preparable;
/**
* MdAction:某型驱动
*/
public class MdAction extends ActionSupport implements ModelDriven<User>,Preparable {
private static final long serialVersionUID = -6933309304624396640L;
private String name;
private Integer uid ;
private User user = new User();
private List<User> userList ;
public String reg() {
return "success";
}
@SkipValidation
public String toRegView() {
System.out.println("toRegView");
return "regView";
}
/**
* 查询所有用户
*/
public String findAllUsers(){
userList = new ArrayList<User>();
User u = null ;
for(int i= 0 ; i < 10 ; i ++){
u = new User();
u.setId(1 + i);
u.setName("tom" + i);
u.setAge(20 + i);
userList.add(u);
}
return "userListView";
}
public String edit(){
return "editView" ;
}
//
public User getModel() {
return user;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public List<User> getUserList() {
return userList;
}
public void setUserList(List<User> userList) {
this.userList = userList;
}
public Integer getUid() {
return uid;
}
public void setUid(Integer uid) {
this.uid = uid;
}
/**
* 该方法在getModel之前运行,在modelDriven拦截器之前先运行
*/
public void prepareDoEdit() throws Exception {
//
User u = new User();
u.setId(uid);
u.setName("jerry");
u.setAge(30);
user = u ;
}
public void prepare() throws Exception {
}
}
struts配置文件md.xml， 需要添加paramsPrepareParamsStack， 在prepare之前填充参数。
<?xml version="1.0"?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN"
"http://struts.apache.org/dtds/struts-2.1.7.dtd">
<struts>
<package name="MdPkg" namespace="/md" extends="struts-default">
<action name="MdAction_*" class="cn.itcast.struts2.modeldriven.MdAction" method="{1}">
<result name="success">/md/reg.jsp</result>
<result name="regView">/md/reg.jsp</result>
<result name="editView">/md/edit.jsp</result>
<result name="userListView">/md/userList.jsp</result>
<interceptor-ref name="paramsPrepareParamsStack" />
</action>
</package>
</struts>
