bluetreetag.java

一款功能强大的树状菜单

package blue.lip.tags;

/**
 * Author：李鹏
 * CreateDate：2006-11-15
 * Modifier：李鹏
 * ModifyDate：2006-11-15
 * Version:1.0
 * Copyright(c)2006 李鹏
 * All right reserved.
 */

import javax.servlet.jsp.tagext.Tag;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.JspException;
import java.io.IOException;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.JspWriter;
import java.util.List;

/**
 * 树标签处理类
 */

public class BlueTreeTag
    implements Tag {
  private PageContext pageContext;
  private Tag parent;
  public static String rootId; //根节点ID
  public static String blueClass; //根据节点ID获得所有该节点子节点的实现类
  public static String blueURL; //点击节点超连接---isUseDataURL为false时有用
  public static boolean isUseDataURL; //是否使用节点封装对象的节点超连接
  public static String rootName; //根节点名称
  public static String imageURL; //所有图片目录路径
  public static String rootImage; //根节点图片
  public static String folderImg; //有子节点关闭图片
  public static String folderOpenImg; //有子节点展开图片
  public static String fileImg; //无子节点图片
  public static String openImg; //节点展开图片
  public static String closeImg; //节点关闭图片
  public static String elementLineImg; //带有节点的线图片
  public static String lineImg; //无节点的线图片
  public static String endLineImg; //最后一个节点线图片
  public static String endFolderOpenImg; //最后一个有子节点展开图片
  public static String endFolderCloseImg; //最后一个有子节点关闭图片
  public static boolean isFolderURL; //是否给有子节点的节点加超连接---isUseDataURL为false时有用
  public static String rootURL; //根节点连接
  public static String target; //所有连接的target属性
  public static String linkClass; //超连接样式
  public static String styleClass; //总样式
  public static String imgClass; //图片样式
  public static String useDataImg; //节点图片是否使用数据类图片，no为不使用，first为仅第一级目录使用，all全部使用
  public static String js; //设置JS文件位置
  public static String onMouseOver; //鼠标经过每个节点时的样式
  public static String onMouseOut; //鼠标离开每个节点时的样式

  public BlueTreeTag() {
    super();
    this.rootId = "0";
    this.blueClass = null; //必须设置
    this.blueURL = "#";
    this.isUseDataURL = false;
    this.rootName = "根节点";
    this.rootImage = "rootImage.gif";
    this.imageURL = null; //必须设置
    this.folderImg = "folder.gif";
    this.folderOpenImg = "folderOpen.gif";
    this.fileImg = "file.gif";
    this.openImg = "open.gif";
    this.closeImg = "close.gif";
    this.elementLineImg = "elementLine.gif";
    this.lineImg = "line.gif";
    this.endLineImg = "endLine.gif";
    this.endFolderOpenImg = "endFolderOpen.gif";
    this.endFolderCloseImg = "endFolderClose.gif";
    this.isFolderURL = true;
    this.rootURL = "#";
    this.target = "_blank";
    this.linkClass="";
    this.imgClass="";
    this.styleClass="";
    this.useDataImg="no";
    this.js=null; //必须设置
    this.onMouseOver="onMouseOver";
    this.onMouseOut="onMouseOut";
  }

  /**
   * 设置标签的页面上下文
   * @param pageContext
   */
  public void setPageContext(PageContext pageContext) {
    this.pageContext = pageContext;
  }

  /**
   * 设置上一级标签
   * @param t
   */
  public void setParent(Tag parent) {
    this.parent = parent;
  }

  public Tag getParent() {
    return this.parent;
  }

  /**
   * 开始标签时的操作
   * @return
   * @throws JspException
   */
  public int doStartTag() throws JspException {
    if(this.blueClass==null){
      throw new JspException("树标签blueClass属性未设置！");
    }
    if(this.imageURL==null){
      throw new JspException("树标签imageURL属性未设置！");
    }
    if(this.js==null){
      throw new JspException("树标签js属性未设置！");
    }
    return this.SKIP_BODY; //返回SKIP_BODY，表示不计算标签体
  }

  /**
   * 结束标签时的操作
   * @return
   * @throws JspException
   */
  public int doEndTag() throws JspException {
    JspWriter out = this.pageContext.getOut();

    try {
      String tree = this.createTree();

      out.print(tree);
    }
    catch (Exception ex) {
      throw new JspException("创建树错误:" + ex.getMessage());
    }

    return this.EVAL_PAGE;
  }

  /**
   * Release 用于释放标签程序占用的资源，比如使用了数据库连接，那么应该关闭这个连接
   */
  public void release() {
  }

  /**
   * 构建树
   * @return 返回树HTML代码字符串
   */
  public String createTree() throws Exception {
    StringBuffer result = new StringBuffer();

    BlueTreeFactory treeFactory = new BlueTreeFactory();
    BlueTreeInterFace tree = (BlueTreeInterFace) treeFactory.create(this.
        blueClass);

    List elements = null;
    elements = tree.getTreeElements(this.rootId);

    //样式
    result.append("<style>");
    result.append(".onMouseOver{");
    result.append("background-color:#CCCCCC;");
    result.append("}");
    result.append(".onMouseOut{");
    result.append("}");
    result.append("</style>");

    //js
    result.append("<script src=\"");
    result.append(this.js);
    result.append("\">");
    result.append("</script>");

    //开始创建树
    result.append("<table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" class=\"");
    result.append(this.styleClass);
    result.append("\">");

    //创建跟节点
    result.append("<tr onMouseOver=\"this.className='");
    result.append(this.onMouseOver);
    result.append("'\" onMouseOut=\"this.className='");
    result.append(this.onMouseOut);
    result.append("'\">");
    result.append("<td>");
    result.append("<a class=\"");
    result.append(this.linkClass);
    result.append("\" href=\"");
    result.append(this.rootURL);
    result.append("\" target=\"");
    result.append(this.target);
    result.append("\">");
    result.append("<img align=\"absmiddle\" class=\"");
    result.append(this.imgClass);
    result.append("\" src=\"");
    result.append(this.imageURL);
    result.append(this.rootImage);
    result.append("\">");
    result.append(this.rootName);
    result.append("</a>");
    result.append("</td>");
    result.append("</tr>");

    //创建第一级节点
    for (int i = 0; i < elements.size(); i++) {
      BlueTreeData treeData = new BlueTreeData();
      treeData = (BlueTreeData) elements.get(i);
      //加超连接头
      //===================================================
      result.append("<tr onMouseOver=\"this.className='");
      result.append(this.onMouseOver);
      result.append("'\" onMouseOut=\"this.className='");
      result.append(this.onMouseOut);
      result.append("'\">");
      result.append("<td>");
      result.append("<a class=\"");
      result.append(this.linkClass);
      result.append("\" href=\"");

      if((treeData.isIschild() && this.isIsFolderURL()) || !treeData.isIschild()){
        if(this.isIsUseDataURL()){
          result.append(treeData.getUrl());
        }else{
          result.append(this.blueURL);
        }
        //添加节点连接参数
        result.append("?");
        result.append("node=");
        result.append(treeData.getId());
      }else{
        result.append("javascript:void(null);");
      }

      result.append("\" target=\"");
      result.append(this.target);
      //添加节点单击事件
      //===================================================
      if(treeData.isIschild()){
        result.append("\" onClick=\"clickTreeNode('");
        result.append(treeData.getId());
        result.append("',1,'");
        result.append(this.styleClass);
        result.append("','");
        result.append(this.imageURL);
        result.append("','");
        result.append(this.imgClass);
        result.append("','");
        result.append(this.lineImg);
        result.append("','");
        result.append(this.endLineImg);
        result.append("','");
        if(this.useDataImg.equalsIgnoreCase("first") || this.useDataImg.equalsIgnoreCase("all")){
          result.append(treeData.getOpenimg());
        }else{
          result.append(this.fileImg);
        }
        result.append("','");
        if ( (i + 1) != elements.size()) {
          result.append(this.openImg);
          result.append("','");
          result.append(this.closeImg);
        }else{
          result.append(this.endFolderOpenImg);
          result.append("','");
          result.append(this.endFolderCloseImg);
        }
        result.append("','");
        if(this.useDataImg.equalsIgnoreCase("first") || this.useDataImg.equalsIgnoreCase("all")){
          result.append(treeData.getOpenimg());
          result.append("','");
          result.append(treeData.getCloseimg());
        }else{
          result.append(this.folderOpenImg);