JSP 动态树的实现

第一步：在开始之前我们需要准备这么一个js文件，代码如下。我姑且将它命名为tree.js。
复制代码 代码如下:
function Node(id, pid, name, url, title, target, icon, iconOpen, open, appendedStr) {
    this.id = id;
    this.pid = pid;
    this.name = name;
    this.url = url;
    this.title = title;
    this.target = target;

    this.icon = icon;
    this.iconOpen = iconOpen;

    this.appendedStr = appendedStr;

    this._io = open || false;
    this._is = false;
    this._ls = false;
    this._hc = false;
    this._ai = 0;
    this._p;
};
// Tree object
function tree(objName,path) {
    this.path = path;
    this.config = {
        target                    : null,
        folderLinks            : true,
        useSelection        : true,
        useCookies            : true,
        useLines                : true,
        useIcons                : true,
        useStatusText        : false,
        closeSameLevel    : false,
        inOrder                    : false
    }
    this.icon = {
        root                : path + 'TreeDemo/images/tree_base.gif',
        folder            : path + 'TreeDemo/images/tree_folder.gif',
        folderOpen    : path + 'TreeDemo/images/tree_folderopen.gif',
        node                : path + 'TreeDemo/images/tree_folder.gif',
        empty                : path + 'TreeDemo/images/tree_empty.gif',
        line                : path + 'TreeDemo/images/tree_line.gif',
        join                : path + 'TreeDemo/images/tree_join.gif',
        joinBottom    : path + 'TreeDemo/images/tree_joinbottom.gif',
        plus                : path + 'TreeDemo/images/tree_plus.gif',
        plusBottom    : path + 'TreeDemo/images/tree_plusbottom.gif',
        minus                : path + 'TreeDemo/images/tree_minus.gif',
        minusBottom    : path + 'TreeDemo/images/tree_minusbottom.gif',
        nlPlus            : path + 'TreeDemo/images/tree_nolines_plus.gif',
        nlMinus            : path + 'TreeDemo/images/tree_nolines_minus.gif'
    };
    this.obj = objName;
    this.aNodes = [];
    this.aIndent = [];
    this.root = new Node(-1);
    this.selectedNode = null;
    this.selectedFound = false;
    this.completed = false;
};
// Adds a new node to the node array
tree.prototype.add = function(id, pid, name, url, title, target, icon, iconOpen, open, appendedStr) {
    this.aNodes[this.aNodes.length] = new Node(id, pid, name, url, title, target, icon, iconOpen, open, appendedStr);
};
// Open/close all nodes
tree.prototype.openAll = function() {
    this.oAll(true);
};
tree.prototype.closeAll = function() {
    this.oAll(false);
};
// Outputs the tree to the page
tree.prototype.toString = function() {
    var str = '\n';
    if (document.getElementById) {
        if (this.config.useCookies) this.selectedNode = this.getSelected();
        str += this.addNode(this.root);
    } else str += 'Browser not supported.';
    str += '<>';
    if (!this.selectedFound) this.selectedNode = null;
    this.completed = true;
    return str;
};
// Creates the tree structure
tree.prototype.addNode = function(pNode) {
    var str = '';
    var n=0;
    if (this.config.inOrder) n = pNode._ai;
    for (n; n        if (this.aNodes[n].pid == pNode.id) {
            var cn = this.aNodes[n];
            cn._p = pNode;
            cn._ai = n;
            this.setCS(cn);
            if (!cn.target && this.config.target) cn.target = this.config.target;
            if (cn._hc && !cn._io && this.config.useCookies) cn._io = this.isOpen(cn.id);
            if (!this.config.folderLinks && cn._hc) cn.url = null;
            if (this.config.useSelection && cn.id == this.selectedNode && !this.selectedFound) {
                    cn._is = true;
                    this.selectedNode = n;
                    this.selectedFound = true;
            }
            str += this.node(cn, n);
            if (cn._ls) break;
        }
    }
    return str;
};
// Creates the node icon, url and text
tree.prototype.node = function(node, nodeId) {
    var str = '' + this.indent(node, nodeId);
    if (this.config.useIcons) {
        if (!node.icon) node.icon = (this.root.id == node.pid) ? this.icon.root : ((node._hc) ? this.icon.folder : this.icon.node);
        if (!node.iconOpen) node.iconOpen = (node._hc) ? this.icon.folderOpen : this.icon.node;
        if (this.root.id == node.pid) {
            node.icon = this.icon.root;
            node.iconOpen = this.icon.root;
        }
        str += '';
    }
    if (node.url) {
        str += '        if (node.title) str += ' title="' + node.title + '"';
        if (node.target) str += ' target="' + node.target + '"';
        if (this.config.useStatusText) str += ' onmouseover="window.status=\'' + node.name + '\';return true;" onmouseout="window.status=\'\';return true;" ';
        if (this.config.useSelection && ((node._hc && this.config.folderLinks) || !node._hc))
            str += ' onclick="javascript: ' + this.obj + '.s(' + nodeId + ');"';
        str += '>';
    }
    else if ((!this.config.folderLinks || !node.url) && node._hc && node.pid != this.root.id)
        str += '';
    str += node.name;
    if (node.url || ((!this.config.folderLinks || !node.url) && node._hc)) str += '';

    //[!--begin--]add by wangxr to append str
    if(node.appendedStr) str += node.appendedStr;
    //[!--end--]
    str += '<>';
    if (node._hc) {
        str += '';
        str += this.addNode(node);
        str += '<>';
    }
    this.aIndent.pop();
    return str;
};
// Adds the empty and line icons
tree.prototype.indent = function(node, nodeId) {
    var str = '';
    if (this.root.id != node.pid) {
        for (var n=0; n            str += '';
        (node._ls) ? this.aIndent.push(0) : this.aIndent.push(1);
        if (node._hc) {
            str += '';
        } else str += '';
    }
    return str;
};
// Checks if a node has any children and if it is the last sibling
tree.prototype.setCS = function(node) {
    var lastId;
    for (var n=0; n        if (this.aNodes[n].pid == node.id) node._hc = true;
        if (this.aNodes[n].pid == node.pid) lastId = this.aNodes[n].id;
    }
    if (lastId==node.id) node._ls = true;
};
// Returns the selected node
tree.prototype.getSelected = function() {
    var sn = this.getCookie('cs' + this.obj);
    return (sn) ? sn : null;
};
// Highlights the selected node
tree.prototype.s = function(id) {
    if (!this.config.useSelection) return;
    var cn = this.aNodes[id];
    if (cn._hc && !this.config.folderLinks) return;
    if (this.selectedNode != id) {
        if (this.selectedNode || this.selectedNode==0) {
            eOld = document.getElementById("s" + this.obj + this.selectedNode);
            eOld.className = "node";
        }
        eNew = document.getElementById("s" + this.obj + id);
        eNew.className = "nodeSel";
        this.selectedNode = id;
        if (this.config.useCookies) this.setCookie('cs' + this.obj, cn.id);
    }
};
// Toggle Open or close
tree.prototype.o = function(id) {
    var cn = this.aNodes[id];
    this.nodeStatus(!cn._io, id, cn._ls);
    cn._io = !cn._io;
    if (this.config.closeSameLevel) this.closeLevel(cn);
    if (this.config.useCookies) this.updateCookie();
};
// Open or close all nodes
tree.prototype.oAll = function(status) {
    for (var n=0; n        if (this.aNodes[n]._hc && this.aNodes[n].pid != this.root.id) {
            this.nodeStatus(status, n, this.aNodes[n]._ls)
            this.aNodes[n]._io = status;
        }
    }
    if (this.config.useCookies) this.updateCookie();
};
// Opens the tree to a specific node
tree.prototype.openTo = function(nId, bSelect, bFirst) {
    if (!bFirst) {
        for (var n=0; n            if (this.aNodes[n].id == nId) {
                nId=n;
                break;
            }
        }
    }
    var cn=this.aNodes[nId];
    if (cn.pid==this.root.id || !cn._p) return;
    cn._io = true;
    cn._is = bSelect;
    if (this.completed && cn._hc) this.nodeStatus(true, cn._ai, cn._ls);
    if (this.completed && bSelect) this.s(cn._ai);
    else if (bSelect) this._sn=cn._ai;
    this.openTo(cn._p._ai, false, true);
};
// Closes all nodes on the same level as certain node
tree.prototype.closeLevel = function(node) {
    for (var n=0; n        if (this.aNodes[n].pid == node.pid && this.aNodes[n].id != node.id && this.aNodes[n]._hc) {
            this.nodeStatus(false, n, this.aNodes[n]._ls);
            this.aNodes[n]._io = false;
            this.closeAllChildren(this.aNodes[n]);
        }
    }
}
// Closes all children of a node
tree.prototype.closeAllChildren = function(node) {
    for (var n=0; n        if (this.aNodes[n].pid == node.id && this.aNodes[n]._hc) {
            if (this.aNodes[n]._io) this.nodeStatus(false, n, this.aNodes[n]._ls);
            this.aNodes[n]._io = false;
            this.closeAllChildren(this.aNodes[n]);        
        }
    }
}
// Change the status of a node(open or closed)
tree.prototype.nodeStatus = function(status, id, bottom) {
    eDiv    = document.getElementById('d' + this.obj + id);
    eJoin    = document.getElementById('j' + this.obj + id);
    if (this.config.useIcons) {
        eIcon    = document.getElementById('i' + this.obj + id);
        eIcon.src = (status) ? this.aNodes[id].iconOpen : this.aNodes[id].icon;
    }
    eJoin.src = (this.config.useLines)?
    ((status)?((bottom)?this.icon.minusBottom:this.icon.minus):((bottom)?this.icon.plusBottom:this.icon.plus)):
    ((status)?this.icon.nlMinus:this.icon.nlPlus);
    eDiv.style.display = (status) ? 'block': 'none';
};
// [Cookie] Clears a cookie
tree.prototype.clearCookie = function() {
    var now = new Date();
    var yesterday = new Date(now.getTime() - 1000 * 60 * 60 * 24);
    this.setCookie('co'+this.obj, 'cookieValue', yesterday);
    this.setCookie('cs'+this.obj, 'cookieValue', yesterday);
};
// [Cookie] Sets value in a cookie
tree.prototype.setCookie = function(cookieName, cookieValue, expires, path, domain, secure) {
    document.cookie =
        escape(cookieName) + '=' + escape(cookieValue)
        + (expires ? '; expires=' + expires.toGMTString() : '')
        + (path ? '; path=' + path : '')
        + (domain ? '; domain=' + domain : '')
        + (secure ? '; secure' : '');
};
// [Cookie] Gets a value from a cookie
tree.prototype.getCookie = function(cookieName) {
    var cookieValue = '';
    var posName = document.cookie.indexOf(escape(cookieName) + '=');
    if (posName != -1) {
        var posValue = posName + (escape(cookieName) + '=').length;
        var endPos = document.cookie.indexOf(';', posValue);
        if (endPos != -1) cookieValue = unescape(document.cookie.substring(posValue, endPos));
        else cookieValue = unescape(document.cookie.substring(posValue));
    }
    return (cookieValue);
};
// [Cookie] Returns ids of open nodes as a string
tree.prototype.updateCookie = function() {
    var str = '';
    for (var n=0; n        if (this.aNodes[n]._io && this.aNodes[n].pid != this.root.id) {
            if (str) str += '.';
            str += this.aNodes[n].id;
        }
    }
    this.setCookie('co' + this.obj, str);
};
// [Cookie] Checks if a node id is in a cookie
tree.prototype.isOpen = function(id) {
    var aOpen = this.getCookie('co' + this.obj).split('.');
    for (var n=0; n        if (aOpen[n] == id) return true;
    return false;
};
// If Push and pop is not implemented by the browser
if (!Array.prototype.push) {
    Array.prototype.push = function array_push() {
        for(var i=0;i            this[this.length]=arguments[i];
        return this.length;
    }
};
if (!Array.prototype.pop) {
    Array.prototype.pop = function array_pop() {
        lastElement = this[this.length-1];
        this.length = Math.max(this.length-1,0);
        return lastElement;
    }
};

由于代码太长，我这里就不给大家拿来细讲了，我们只要会用就OK。就像猪肉我们能吃就OK，不一定非要知道猪养。
第二步：创建数据库，创建数据库的代码如下，我这边使用的是MySQL数据为。
create database `treedemo`;
use treedemo;
create table trees(
tid int primary key not null,
pid int not null,
tname varchar(50) not null,
isleaf int
);
select * from trees;
insert into trees(tid,pid,tname)values(0,-1,'组织内容');
insert into trees(tid,pid,tname)values(1,0,'短信');
insert into trees(tid,pid,tname)values(2,0,'彩信');
insert into trees(tid,pid,tname)values(3,0,'新闻');
insert into trees(tid,pid,tname)values(4,1,'移动生活');
insert into trees(tid,pid,tname)values(5,1,'单条滚动点播');
insert into trees(tid,pid,tname)values(6,2,'定制');
insert into trees(tid,pid,tname)values(7,2,'点播');
insert into trees(tid,pid,tname)values(8,3,'房产频道');
insert into trees(tid,pid,tname)values(9,3,'农村频道');
insert into trees(tid,pid,tname)values(10,3,'数码频道');
insert into trees(tid,pid,tname)values(11,6,'幽默笑话');
insert into trees(tid,pid,tname)values(12,7,'铃声');
insert into trees(tid,pid,tname)values(13,7,'贺卡');
insert into trees(tid,pid,tname)values(14,7,'动画');
insert into trees(tid,pid,tname)values(15,13,'贺卡1');
insert into trees(tid,pid,tname)values(16,13,'贺卡2');
insert into trees(tid,pid,tname)values(17,13,'贺卡3');
insert into trees(tid,pid,tname)values(18,13,'贺卡4');
select * from trees;
表字段的说明：
（1）tid表示节点的编号；
（2）pid 该节点父节点的编号；
（3）tname 节点名称；
（4）isleaf 表明该节点是否为叶节点，叶节点为1，非叶节点为0。该字段可根据实际情况增删。

第三步：在myeclipse中创建一个WEB工程，命名为“TreeDemo”。在WebRoot文件夹下创建js文件夹、css文件夹、images文件夹分别用来存放.js文件、.css文件和项目中用到的图片文件。
第四步：编写数据库连接类，其中的用户名、密码需要根据你数据库情况进行修改，代码如下。
复制代码 代码如下:
package com.sx.mas.utils;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBConn {
private static final String DRIVER="com.mysql.jdbc.Driver";
private static final String URL="jdbc:mysql://localhost:3306/treedemo";
Connection conn=null;
public Connection getConnection(){
try {
Class.forName(DRIVER);
conn=DriverManager.getConnection(URL,"root","root");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return conn;
}
}
package com.sx.mas.utils;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBConn {
    private static final String DRIVER="com.mysql.jdbc.Driver";
    private static final String URL="jdbc:mysql://localhost:3306/treedemo";
    Connection conn=null;
    public Connection getConnection(){
        try {
            Class.forName(DRIVER);
            conn=DriverManager.getConnection(URL,"root","root");
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return conn;
    }
}

第五步：编写javabean类，代码如下，
复制代码 代码如下:
package com.sx.mas.beans;
public class TreeNode {
private int tid;
private int pid;
private String tname;
private int isleaf;
public int getTid() {
return tid;
}
public void setTid(int tid) {
this.tid = tid;
}
public int getPid() {
return pid;
}
public void setPid(int pid) {
this.pid = pid;
}
public String getTname() {
return tname;
}
public void setTname(String tname) {
this.tname = tname;
}
public int getIsleaf() {
return isleaf;
}
public void setIsleaf(int isleaf) {
this.isleaf = isleaf;
}
}
package com.sx.mas.beans;
public class TreeNode {
    private int tid;
    private int pid;
    private String tname;
    private int isleaf;

    public int getTid() {
        return tid;
    }
    public void setTid(int tid) {
        this.tid = tid;
    }
    public int getPid() {
        return pid;
    }
    public void setPid(int pid) {
        this.pid = pid;
    }
    public String getTname() {
        return tname;
    }
    public void setTname(String tname) {
        this.tname = tname;
    }
    public int getIsleaf() {
        return isleaf;
    }
    public void setIsleaf(int isleaf) {
        this.isleaf = isleaf;
    }
}

第六步：创建相关的DAO类，代码如下。DAO类将数据库表装保存到Vector对象中。
复制代码 代码如下:
package com.sx.mas.beans;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Vector;
import com.sx.mas.utils.DBConn;
public class TreeDAO {
public Vector getTree(){
Vector vec = new Vector();
DBConn dbconn = new DBConn();
Connection conn = dbconn.getConnection();
try {
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("select * from trees");
while(rs.next()){
TreeNode treenode = new TreeNode();
treenode.setTid(rs.getInt("tid"));
treenode.setPid(rs.getInt("pid"));
treenode.setTname(rs.getString("tname"));
treenode.setIsleaf(rs.getInt("isleaf"));
vec.add(treenode);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return vec;
}
}
package com.sx.mas.beans;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Vector;
import com.sx.mas.utils.DBConn;
public class TreeDAO {
    public Vector getTree(){
        Vector vec = new Vector();
        DBConn dbconn = new DBConn();
        Connection conn = dbconn.getConnection();
        try {
            Statement stmt = conn.createStatement();
            ResultSet rs = stmt.executeQuery("select * from trees");
            while(rs.next()){
                TreeNode treenode = new TreeNode();
                treenode.setTid(rs.getInt("tid"));
                treenode.setPid(rs.getInt("pid"));
                treenode.setTname(rs.getString("tname"));
             treenode.setIsleaf(rs.getInt("isleaf"));
                vec.add(treenode);
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return vec;
    }
}

第七步：页面上显示树状结构。在TreeDemo中创建show_tree.jsp页面，代码如下。
复制代码 代码如下:
<%@ page language="java" import="java.util.*" contentType="text/html; charset=gb2312"%>
<%@ page import="com.sx.mas.beans.*" %>

background=images/tree_bg.gif border=0> width=147 useMap=#Map border=0>

<%@ page language="java" import="java.util.*" contentType="text/html; charset=gb2312"%>
<%@ page import="com.sx.mas.beans.*" %>







    
    
    
    
    
    


    
        
            
        
    

background=images/tree_bg.gif border=0> width=147 useMap=#Map border=0>

第八步：创建一个框架页面，index.html代码如下，和list_default.htm。
复制代码 代码如下:



type=text/css rel=stylesheet>

frameSpacing=0 rows=* frameBorder=0>


<BR><body> <BR></body> <BR>



type=text/css rel=stylesheet>

frameSpacing=0 rows=* frameBorder=0>


<BR><body> <BR></body> <BR>


第九步：运行效果
备注：如有需要源码的请直接联系QQ398349538。