treecontrol.java

Java/J2EE框架Jdon-Framework系统的Sample

/**
 * Copyright 2005 Jdon.com
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

package com.jdon.strutsutil.treeview;

import java.io.Serializable;
import java.util.*;

/**
 * 树形结构控制类，被类被保存在用户Session中，
 * 用以记载树形结构的一些特点。
 *
 *
 * ViewNode是记录节点微观信息，聚焦每个节点
 * 该类则关注根节点和所有节点。
 *
 * 和节点ViewNode共同使用，可记录树形结构的全部信息
 *
 */

public class TreeControl implements Serializable {

  public static boolean init = true; //是否初始化
  //当前选中的节点
  private ViewNode selected = null;
  private ViewNode root = null;
  private HashMap registry = new HashMap();


  public TreeControl(ViewNode root) {
    this.root = root;
    root.setTree(this);
    root.setLast(true);
  }

  public ViewNode getRoot() {
    return (this.root);
  }


  public ViewNode findNode(String key) {
    return ( (ViewNode) registry.get(key));
  }

  public void selectNode(String key) {
    if (selected != null) {
      selected.setSelected(false);
      selected = null;
    }
    selected = findNode(key);
    if (selected != null)
      selected.setSelected(true);

  }

  public void addNode(ViewNode node) throws
      IllegalArgumentException {
    node.setTree(this);
    registry.put(node.getKey(), node);
  }

  public int getTreeWidth() {
    if (root == null)
      return (0);
    else
      return (getWidth(root));

  }

  /**
   * 该节点到树底端的距离
   * 与node.getDepth()区别：
   * 后者是该节点到树顶的距离。
   * @param node
   * @return
   */
  public int getWidth(ViewNode node) {
    int width = node.getDepth();
    ViewNode children[] = node.findChildren();
    for (int i = 0; i < children.length; i++) {
      int current = getWidth(children[i]);
      if (current > width)
        width = current;
    }
    return (width);
  }


}