Struts2 OGNL
Struts2 OGNL
OGNL是Object-Graph Navigation Language的缩写，全称为对象图导航语言，是一种功能强大的表达式语言，它通过简单一致的语法，可以任意存取对象的属性或者调用对象的方法，能够遍历整个对象的结构图，实现对象属性类型的转换等功能。
实战
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<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>
OGNL:object graph navigation language<br/>
<a href="/ognl.action?ip=100.22.33.22&uv=100&pv=50&user_model.school=1111222&bbs_model.tites_model.author=author">OGNL访问</a>
《备注：OGNL 只有传递参数的时候才构造对象传递参数值或者使用domain model的时候可以自己new》
</body>
</html>
struts.xml
<constant name="struts.ognl.allowStaticMethodAccess" value="true"></constant> <package name="default" namespace="/" extends="struts-default"> <action name="ognl" class="com.struts2.action.OGNLController"> <result>/ognl.jsp</result> </action> </package>
OGNLController.java
package com.struts2.action;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import com.opensymphony.xwork2.ActionSupport;
import com.summary.model.BBSModel;
import com.summary.model.UserModel;
public class OGNLController extends ActionSupport {
private String ip;
private String uv;
private String pv;
private UserModel user_model;
private BBSModel bbs_model;
private List dataList = new ArrayList();
private Set dataSet =new HashSet();
private Map<String, String> dataMap = new HashMap();
private List<UserModel> dataInfoList ; //在页面中获取不到对象的值，需要查看对象是否设置了set,get方法
public String execute() {
dataList.add("list_001");
dataList.add("list_002");
dataList.add("list_003");
dataList.add("list_004");
dataList.add("list_005");
dataList.add("list_006");
dataList.add("list_007");
dataList.add("list_008");
dataSet.add("set_001");
dataSet.add("set_002");
dataSet.add("set_003");
dataSet.add("set_004");
dataSet.add("set_005");
dataSet.add("set_006");
dataSet.add("set_007");
dataSet.add("set_008");
dataMap.put("data_key_001", "data_value_001");
dataMap.put("data_key_002", "data_value_002");
dataMap.put("data_key_003", "data_value_003");
dataMap.put("data_key_004", "data_value_004");
dataMap.put("data_key_005", "data_value_005");
dataMap.put("data_key_006", "data_value_006");
dataInfoList = new ArrayList<UserModel>();
UserModel userModel1 = new UserModel();
userModel1.setUser_name("user_name_01");
userModel1.setSchool("用户的学校");
userModel1.setRemark("备注user_name_01");
userModel1.setPassword("密码用户名称01");
userModel1.setAge(15);
dataInfoList.add(userModel1);
UserModel userModel2 = new UserModel();
userModel2.setUser_name("user_name_02");
userModel2.setSchool("用户的学校02");
userModel2.setRemark("备注user_name_02");
userModel2.setPassword("密码用户名称02");
userModel2.setAge(33);
dataInfoList.add(userModel2);
UserModel userModel3 = new UserModel();
userModel3.setUser_name("user_name_032");
userModel3.setSchool("用户的学校03");
userModel3.setRemark("备注user_name_03");
userModel3.setPassword("密码用户名称03");
userModel3.setAge(2);
dataInfoList.add(userModel3);
UserModel userModel4 = new UserModel();
userModel4.setUser_name("user_name_04");
userModel4.setSchool("用户的学校04");
userModel4.setRemark("备注user_name_04");
userModel4.setPassword("密码用户名称04");
userModel4.setAge(22);
dataInfoList.add(userModel4);
return SUCCESS;
}
public String test() {
return "访问Action值栈中的普通方法";
}
public String getIp() {
return ip;
}
public void setIp(String ip) {
this.ip = ip;
}
public String getUv() {
return uv;
}
public void setUv(String uv) {
this.uv = uv;
}
public String getPv() {
return pv;
}
public void setPv(String pv) {
this.pv = pv;
}
public UserModel getUser_model() {
return user_model;
}
public void setUser_model(UserModel user_model) {
this.user_model = user_model;
}
public BBSModel getBbs_model() {
return bbs_model;
}
public void setBbs_model(BBSModel bbs_model) {
this.bbs_model = bbs_model;
}
public List getDataList() {
return dataList;
}
public void setDataList(List dataList) {
this.dataList = dataList;
}
public Set getDataSet() {
return dataSet;
}
public void setDataSet(Set dataSet) {
this.dataSet = dataSet;
}
public Map<String, String> getDataMap() {
return dataMap;
}
public void setDataMap(Map<String, String> dataMap) {
this.dataMap = dataMap;
}
public List<UserModel> getDataInfoList() {
return dataInfoList;
}
public void setDataInfoList(List<UserModel> dataInfoList) {
this.dataInfoList = dataInfoList;
}
}
StaticController.java
package com.struts2.action;
import com.opensymphony.xwork2.ActionSupport;
public class StaticController {
public static String CONFIG="配置文件";
public StaticController() {
System.out.println("xxxxxxxxxxxxxx");
}
public static String getStaticMethod() {
return "访问静态方法";
}
public static String getCONFIG() {
return CONFIG;
}
public static void setCONFIG(String config) {
CONFIG = config;
}
}
BBSModel.java
package com.summary.model;
public class BBSModel {
private String title;
private TitesModel tites_model;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public TitesModel getTites_model() {
return tites_model;
}
public void setTites_model(TitesModel tites_model) {
this.tites_model = tites_model;
}
}
TitesModel.java
package com.summary.model;
public class TitesModel {
private String author="朱诞生";
private String content="帖子内容";
private String times="2011-12-04";
private String reply_to="暂时无人回复";
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
public String getTimes() {
return times;
}
public void setTimes(String times) {
this.times = times;
}
public String getReply_to() {
return reply_to;
}
public void setReply_to(String reply_to) {
this.reply_to = reply_to;
}
}
UserModel.java
package com.summary.model;
public class UserModel {
private String user_name="";
private String password="";
private String school="";
private String remark="";
private int age;
private String add_date;
public String getUser_name() {
return user_name;
}
public void setUser_name(String user_name) {
this.user_name = user_name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getSchool() {
return school;
}
public void setSchool(String school) {
this.school = school;
}
public String getRemark() {
return remark;
}
public void setRemark(String remark) {
this.remark = remark;
}
public String getData() {
return "访问值栈中对象的普通方法";
}
public String getAdd_date() {
return add_date;
}
public void setAdd_date(String add_date) {
this.add_date = add_date;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
OGNL: 对象图导航语言
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="/struts-tags" prefix="s" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'ognl.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>
对象图导航语言<br/>
OGNL是Object-Graph Navigation Language的缩写，全称为对象图导航语言，是一种功能强大的表达式语言，它通过简单一致的语法，可以任意存取对象的属性或者调用对象的方法，能够遍历整个对象的结构图，实现对象属性类型的转换等功能。
<br/>
值栈普通属性和普通方法：<br/>
1:访问ACTION值栈中的普通属性 : ip=<s:property value="ip"/><br/>
2:访问值栈中对象的普通属性 : UserModel.school=<s:property value="user_model.school"/><br/>
3：访问值栈中对象的普通属性 （set，get 方法）: BBSModel.TitesModel.author=<s:property value="bbs_model.tites_model.author"/> 《备注：OGNL 只有传递参数的时候才构造对象传递参数值》<br/>
4：访问值栈中对象的普通方法 :length()= <s:property value="ip.length()"/> | substring()=<s:property value="ip.substring(0,5)"/> <br/>
5：访问值栈中对象的普通方法 : <s:property value="test()"/> | <s:property value="user_model.getData()"/> <br/>
<hr/>
值栈中静态属性和方法：使用@包名@类名 <br/>
1：访问静态属性：<s:property value="@com.struts2.action.StaticController@CONFIG"/><br/>
2：访问静态方法：<s:property value="@com.struts2.action.StaticController@getStaticMethod()"/><br/>
3:访问构造方法：<s:property value="new com.struts2.action.StaticController()"/><br/>
<hr/>
访问数组和集合
<br/>
1:获取List数据：<s:property value="dataList"/> <br/>
2:获取List中的一个元素(数组和集合是一样的访问小标都是从0切使用中括号[])：<s:property value="dataList[4]"/><br/>
3:获取Set数据：<s:property value="dataSet"/><br/>
4：获取Set中的莫一个元素(Set是无序，且不能使用下标获取)：<s:property value="dataSet[3]"/><br/>
5：获取Map数据: <s:property value="dataMap"/><br/>
6：获取Map的所有键：<s:property value="dataMap.keys"/><br/>
7:获取Map的所有值：<s:property value="dataMap.values"/><br/>
8：获取Map中的莫一个元素(使用类似于数组小标获取List的内容):<s:property value="dataMap['data_key_005']"/><br/>
9：获取List的大小<s:property value="dataList.size()"/><br/>
<hr/>
访问集合 – 投影、选择(? ^ $)
<br/>
1：选择获取年龄18岁以上的集合: <s:property value="dataInfoList.{?#this.age>=18}"/><br/>
2：选择获取年龄18岁以上的对象集合的姓名: <s:property value="dataInfoList.{?#this.age>=18}.{user_name}"/><br/>
3：选择获取年龄18岁以上的对象集合第一个姓名:dataInfoList.{?#this.age>=18}.{user_name}[0]= <s:property value="dataInfoList.{?#this.age>=18}.{user_name}[0]"/><br/>
4：选择获取年龄18岁以上的对象集合第一个姓名: dataInfoList.{^#this.age>=18}.{user_name}=<s:property value="dataInfoList.{^#this.age>=18}.{user_name}"/><br/>
5：选择获取以上的对象集合最后一个姓名: dataInfoList.{$#this.age>=1}.{user_name}=<s:property value="dataInfoList.{$#this.age>=1}.{user_name}"/><br/>
6：选择获取年龄18岁以上的对象集合的姓名的人数: <s:property value="dataInfoList.{?#this.age>=18}.{user_name}.size()"/><br/>
<s:debug></s:debug>
</body>
</html>