纯Struts2 AJAX树实现方式及源码

来源：互联网发布：淘宝客api是什么编辑：程序博客网时间：2024/05/29 16:22

在J2EE开发中不可避免会使用的树（Tree），一般情况有二种实现方式，第一种是初始化的时候将树信息就全部加载到内存中，这种方式适用于小数据或者性能要求不高的情况，优点是加载完后对服务器就不会有压力并且打开树节点速度快；第二种是数据异步加载即ajax技术，每次都加载少量的必须的数据，这种方式适用于大量数据和性能要求较高的情况；我们做为软件设计和开发者都希望软件性能最佳、用户体验最好；

目前网上介绍struts2 ajax tree的实例很多但就是不太全面、完整，就连struts官方网站都没有完整实例；下面我来介绍一下struts2 ajax tree的使用方法及技巧，这个实例全部引用自jdframe开发框架中的组织机构管理功能源码：

1. jsp页面

首先JSP要引用，其次在<head>中包含< sx:head/>

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%@ taglib prefix="s" uri="/struts-tags"%><%@ taglib prefix="sx" uri="/struts-dojo-tags"%><%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>JDFrame System Organization Tree</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">    <meta content="MSHTML 6.00.2600.0" name=GENERATOR><link rel="stylesheet" type="text/css" href="/css/sys/main.css"><style type="text/css">body {margin-left: 0px;margin-top: 0px;margin-right: 0px;margin-bottom: 0px;SCROLLBAR-FACE-COLOR: #37b0dd;SCROLLBAR-HIGHLIGHT-COLOR:#ffffff;SCROLLBAR-SHADOW-COLOR: #ffffff;SCROLLBAR-3DLIGHT-COLOR:0099cc;SCROLLBAR-ARROW-COLOR:#1c6787;SCROLLBAR-TRACK-COLOR:#ddfdfd;SCROLLBAR-DARKSHADOW-COLOR:#1c6787;}</style>    <sx:head/>  </head><body><script language="JavaScript" type="text/javascript">    dojo.event.topic.subscribe("treeSelected", function treeNodeSelected(node) {        dojo.io.bind({            url: "<s:url value='/com/jdframe/sys/core/org/treeSelected.action'/>?nodeId="+node.node.widgetId,            load: function(type, data, evt) {                var divDisplay = dojo.byId("displayId");                divDisplay.innerHTML=data;            },            mimeType: "text/html"        });        window.parent.showOrg(node.node.widgetId);    });</script><s:url id="nodesUrl" namespace="/com/jdframe/sys/core/org" action="getNodes" /><table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">  <tr>    <td valign="top" id="td_tree">    <div style="float:left; margin-right: 50px;">       <sx:tree id="dorg_tree" href="%{#nodesUrl}" treeSelectedTopic="treeSelected" />    </div>     </td>  </tr></table> </body></html>

2. Struts2配置文件

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "http://struts.apache.org/dtds/struts-2.0.dtd"><struts><package name="organiztion"  namespace="/com/jdframe/sys/core/org"extends="struts-default" ><actionname = "getNodes" class= "com.jdframe.sys.biz.org.DynamicTreeAction"><resulttype="freemarker">/sys/core/frame/treeAjaxDynamic.ftl</result></action><actionname = "treeSelected" method="selectTreeNode" class= "com.jdframe.sys.biz.org.DynamicTreeAction"><result>/sys/core/org/tree.jsp</result></action>...

3. java代码

AjaxDynamicTreeAction.java

package com.jdframe.sys.core.model.tree;import com.jdframe.sys.core.action.JdframeAction;import com.jdframe.sys.core.model.tree.Category;  // TODO: Auto-generated Javadoc/** * The Path : com.jdframe.sys.core.model.tree.AjaxDynamicTreeAction.java * The   AjaxDynamicTreeAction * Last-Modified-Time : 2014-2-20 10:44:11 * * @author support@jdframe.com * @version  2.0.3.0 *  http://www.jdframe.com * @see  */public abstract class AjaxDynamicTreeAction  extends JdframeAction {//default value/** The node id. */protected String nodeId = null;//for ftl    /** The category. */public Category category;/* (非 Javadoc)* <p>Title: perform</p>* <p>Description: </p>* @return* @see com.jdframe.sys.core.action.JdframeAction#perform()*//* (non-Javadoc) * @see com.jdframe.sys.core.action.JdframeAction#perform() */@Overrideprotected abstract String perform();/** * Select tree node. * * @return the string */public abstract String selectTreeNode() ;/* (非 Javadoc)* <p>Title: validators</p>* <p>Description: </p>* @see com.jdframe.sys.core.action.JdframeAction#validators()*//* (non-Javadoc) * @see com.jdframe.sys.core.action.JdframeAction#validators() */@Overrideprotected abstract void validators() ;/* (非 Javadoc)* <p>Title: initial</p>* <p>Description: </p>* @return* @see com.jdframe.sys.core.action.JdframeAction#initial()*//* (non-Javadoc) * @see com.jdframe.sys.core.action.JdframeAction#initial() */@Overrideprotected abstract String initial()  ;    /**     * Gets the category.     *     * @return the category     */    public Category getCategory() {return category;}/** * Sets the category. * * @param category the new category */public void setCategory(Category category) {this.category = category;}         /**     * Gets the node id.     *     * @return the node id     */    public String getNodeId() {return nodeId;}/** * Sets the node id. * * @param nodeId the new node id */public void setNodeId(String nodeId) {this.nodeId = nodeId;}/**     * Gets the node name.     *     * @return the node name     */    public String getNodeName() {        return category != null ? category.getName() : "Node not found";    } }

业务处理类：DynamicTreeAction.java

package com.jdframe.sys.biz.org;import com.jdframe.sys.core.model.User;import com.jdframe.sys.core.model.tree.AjaxDynamicTreeAction; // TODO: Auto-generated Javadoc /** * The Path : com.jdframe.sys.biz.org.DynamicTreeAction.java * The   DynamicTreeAction * Last-Modified-Time : 2014-2-20 9:55:53 * * @author support@jdframe.com * @version  2.0.3.0 *  http://www.jdframe.com * @see  */public class DynamicTreeAction  extends AjaxDynamicTreeAction {/* (非 Javadoc)* <p>Title: perform</p>* <p>Description: </p>* @return* @see com.jdframe.sys.core.action.JdframeAction#perform()*//* (non-Javadoc) * @see com.jdframe.sys.core.model.tree.AjaxDynamicTreeAction#perform() */@Overrideprotected String perform() {// TODO Auto-generated method stubUser user = this.getUserProfileFromSession().getUser();CategoryImpl cat = new CategoryImpl();if(nodeId == null ){nodeId = user.getUser_zzjg_dm();category = cat.getRootById(nodeId);}else{category = cat.getById(nodeId);}return SUCCESS;}/** * Select tree node. * * @return the string */public String selectTreeNode() {// TODO Auto-generated method stub//category = OrgCategory.getInstance().getById(nodeId);CategoryImpl cat = new CategoryImpl();category = cat.getById(nodeId);return SUCCESS;}/* (非 Javadoc)* <p>Title: validators</p>* <p>Description: </p>* @see com.jdframe.sys.core.action.JdframeAction#validators()*//* (non-Javadoc) * @see com.jdframe.sys.core.model.tree.AjaxDynamicTreeAction#validators() */@Overrideprotected void validators() {// TODO Auto-generated method stub}/* (非 Javadoc)* <p>Title: initial</p>* <p>Description: </p>* @return* @see com.jdframe.sys.core.action.JdframeAction#initial()*//* (non-Javadoc) * @see com.jdframe.sys.core.model.tree.AjaxDynamicTreeAction#initial() */@Overrideprotected String initial() {// TODO Auto-generated method stubreturn null;}}

TREE对象类： Category.java

package com.jdframe.sys.core.model.tree;import java.util.*;// TODO: Auto-generated Javadoc/** * The Path : com.jdframe.sys.core.model.Category.java * The Class Category. * Last-Modified-Time : 2013-12-25 21:32:41 * * @author support@jdframe.com * @see * @version  2.0.3.0 www.jdframe.com */public abstract class Category {/** The id. */protected String id;/** The name. */protected String name;/** The children. */protected List children;/** The cat map. */public Category(){} /**  *  * Title:  getById * Description: TODO(返回包含下级节点的树，初始化后展开节点时执行，一般情况下id为为当前选中的节点) * @param       * @return  Category   *  */public  abstract Category getById(String id);/** * * Title:  getRootById* Description: TODO(返回包含当前节点的树，初始化时执行，一般情况下id为空)* @param      * @return  Category  * */public  abstract Category getRootById(String id);public String getId() {return id;}public void setId(String id) {this.id = id;}/** * Gets the name. * * @return the name */public String getName() {return name;}/** * Sets the name. * * @param name the new name */public void setName(String name) {this.name = name;}/** * Gets the children. * * @return the children */public List getChildren() {return children;}/** * Sets the children. * * @param children the new children */public void setChildren(List children) {this.children = children;} }

TREE对象类： CategoryImpl.java

package com.jdframe.sys.biz.org;import java.util.*;import org.apache.ibatis.session.SqlSession;import org.apache.log4j.Logger;import com.jdframe.sys.core.model.tree.Category;import com.jdframe.sys.core.util.DbUtils;import com.jdframe.sys.dao.model.T_sys_organization;// TODO: Auto-generated Javadoc/** * The Path : com.jdframe.sys.biz.org.CategoryImpl.java * The   CategoryImpl * Last-Modified-Time : 2014-2-20 21:33:19 * @author support@jdframe.com * @version  2.0.3.0 *  http://www.jdframe.com * @see  */public class CategoryImpl extends Category {/** The log. */Logger log = Logger.getLogger(CategoryImpl.class);/** * Instantiates a new category impl. */public CategoryImpl(){}/** * Instantiates a new category impl. * * @param id the id * @param name the name * @param children the children */public CategoryImpl(String id, String name, CategoryImpl... children) {//super(id, name, children);this.id = id;this.name = name;this.children = new ArrayList<CategoryImpl>();for (CategoryImpl child : children) {this.children.add(child);}// TODO Auto-generated constructor stub}/* (non-Javadoc) * @see com.jdframe.sys.core.model.tree.Category#getById(java.lang.String) */@Overridepublic  CategoryImpl getById(String sj_dm){SqlSession session = DbUtils.buildSqlSession();CategoryImpl root_cat  = null;try{ List<T_sys_organization> all = session.selectList("getSubOrgByDm",sj_dm); List allCategory = new ArrayList();for (int j = 0; j < all.size(); j++) { CategoryImpl  self_category  = null;String self_code = all.get(j).getZzjg_dm();String self_name = all.get(j).getZzjg_name();  List<T_sys_organization> l = session.selectList("getSubOrgByDm",self_code);List subCategory = new ArrayList();for (int i = 0; i < l.size(); i++) {String _code = l.get(i).getZzjg_dm();String _name = l.get(i).getZzjg_name();subCategory.add(new CategoryImpl(_code,_name));}if(subCategory.size()>0){CategoryImpl[] childr = new CategoryImpl[subCategory.size()];for (int i = 0; i < subCategory.size(); i++) {if(subCategory.get(i) instanceof CategoryImpl){childr[i] = (CategoryImpl)subCategory.get(i);}}self_category  = new CategoryImpl(self_code,self_name,childr);}else{self_category  = new CategoryImpl(self_code,self_name);}allCategory.add(self_category); }CategoryImpl[] allchildr = new CategoryImpl[allCategory.size()];if(allCategory.size()>0){for (int i = 0; i < allCategory.size(); i++) {if(allCategory.get(i) instanceof CategoryImpl){allchildr[i] = (CategoryImpl)allCategory.get(i);}}root_cat  = new CategoryImpl("-1","Root",allchildr);}else{root_cat  = new CategoryImpl("-1","Root");}//if(sj_dm.equals("76300000000")){//root_cat = self_category;//}}finally{if(session!=null)session.close();}return root_cat; }/* (non-Javadoc) * @see com.jdframe.sys.core.model.tree.Category#getRootById(java.lang.String) */@Overridepublic CategoryImpl getRootById(String id) {// TODO Auto-generated method stubSqlSession session = DbUtils.buildSqlSession();CategoryImpl root_cat  = null;try{ List<T_sys_organization> all = session.selectList("getOrgBySwjgDm",id); List allCategory = new ArrayList();for (int j = 0; j < all.size(); j++) { CategoryImpl  self_category  = null;String self_code = all.get(j).getZzjg_dm();String self_name = all.get(j).getZzjg_name();  List<T_sys_organization> l = session.selectList("getSubOrgByDm",self_code);List subCategory = new ArrayList();for (int i = 0; i < l.size(); i++) {String _code = l.get(i).getZzjg_dm();String _name = l.get(i).getZzjg_name();subCategory.add(new CategoryImpl(_code,_name));}if(subCategory.size()>0){CategoryImpl[] childr = new CategoryImpl[subCategory.size()];for (int i = 0; i < subCategory.size(); i++) {if(subCategory.get(i) instanceof CategoryImpl){childr[i] = (CategoryImpl)subCategory.get(i);}}self_category  = new CategoryImpl(self_code,self_name,childr);}else{self_category  = new CategoryImpl(self_code,self_name);}allCategory.add(self_category); }CategoryImpl[] allchildr = new CategoryImpl[allCategory.size()];if(allCategory.size()>0){for (int i = 0; i < allCategory.size(); i++) {if(allCategory.get(i) instanceof CategoryImpl){allchildr[i] = (CategoryImpl)allCategory.get(i);}}root_cat  = new CategoryImpl("-1","Root",allchildr);}else{root_cat  = new CategoryImpl("-1","Root");}}finally{if(session!=null)session.close();}return root_cat;}  }

应用效果：

6 0