| /* |
| * Copyright 2001,2004 The Apache Software Foundation. |
| * |
| * 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 org.apache.webapp.admin; |
| |
| |
| import java.io.Serializable; |
| import java.util.HashMap; |
| |
| |
| /** |
| * <p>The overall data structure representing a <em>tree control</em> |
| * that can be rendered by the <code>TreeControlTag</code> custom tag. |
| * Each node of the tree is represented by an instance of |
| * <code>TreeControlNode</code>.</p> |
| * |
| * @author Jazmin Jonson |
| * @author Craig R. McClanahan |
| * @version $Revision$ $Date$ |
| */ |
| |
| public class TreeControl implements Serializable { |
| |
| |
| // ----------------------------------------------------------- Constructors |
| |
| |
| /** |
| * Construct a new instance with no predefined root node. |
| */ |
| public TreeControl() { |
| |
| super(); |
| setRoot(null); |
| |
| } |
| |
| |
| /** |
| * Construct a new instance with the specified root node. |
| * |
| * @param root The new root node |
| */ |
| public TreeControl(TreeControlNode root) { |
| |
| super(); |
| setRoot(root); |
| |
| } |
| |
| |
| // ----------------------------------------------------- Instance Variables |
| |
| |
| /** |
| * The collection of nodes that represent this tree, keyed by name. |
| */ |
| protected HashMap registry = new HashMap(); |
| |
| |
| /** |
| * The most recently selected node. |
| */ |
| protected TreeControlNode selected = null; |
| |
| |
| // ------------------------------------------------------------- Properties |
| |
| |
| /** |
| * The root node of the entire tree. |
| */ |
| protected TreeControlNode root = null; |
| |
| public TreeControlNode getRoot() { |
| return (this.root); |
| } |
| |
| protected void setRoot(TreeControlNode root) { |
| if (this.root != null) |
| removeNode(this.root); |
| if (root != null) |
| addNode(root); |
| root.setLast(true); |
| this.root = root; |
| } |
| |
| |
| /** |
| * The current displayable "width" of this tree (that is, the maximum |
| * depth of the visible part of the tree). |
| */ |
| public int getWidth() { |
| |
| if (root == null) |
| return (0); |
| else |
| return (getWidth(root)); |
| |
| } |
| |
| |
| // --------------------------------------------------------- Public Methods |
| |
| |
| /** |
| * Find and return the <code>TreeControlNode</code> for the specified |
| * node name, if it exists; otherwise, return <code>null</code>. |
| * |
| * @param name Name of the <code>TreeControlNode</code> to be returned |
| */ |
| public TreeControlNode findNode(String name) { |
| |
| synchronized (registry) { |
| return ((TreeControlNode) registry.get(name)); |
| } |
| |
| } |
| |
| |
| /** |
| * Mark the specified node as the one-and-only currently selected one, |
| * deselecting any previous node that was so marked. |
| * |
| * @param node Name of the node to mark as selected, or <code>null</code> |
| * if there should be no currently selected node |
| */ |
| public void selectNode(String name) { |
| |
| if (selected != null) { |
| selected.setSelected(false); |
| selected = null; |
| } |
| selected = findNode(name); |
| if (selected != null) |
| selected.setSelected(true); |
| |
| } |
| |
| |
| // -------------------------------------------------------- Package Methods |
| |
| |
| /** |
| * Register the specified node in our registry of the complete tree. |
| * |
| * @param node The <code>TreeControlNode</code> to be registered |
| * |
| * @exception IllegalArgumentException if the name of this node |
| * is not unique |
| */ |
| void addNode(TreeControlNode node) throws IllegalArgumentException { |
| |
| synchronized (registry) { |
| String name = node.getName(); |
| if (registry.containsKey(name)) |
| throw new IllegalArgumentException("Name '" + name + |
| "' is not unique"); |
| node.setTree(this); |
| registry.put(name, node); |
| } |
| |
| } |
| |
| |
| /** |
| * Calculate the width of the subtree below the specified node. |
| * |
| * @param node The node for which to calculate the width |
| */ |
| int getWidth(TreeControlNode node) { |
| |
| int width = node.getWidth(); |
| if (!node.isExpanded()) |
| return (width); |
| TreeControlNode children[] = node.findChildren(); |
| for (int i = 0; i < children.length; i++) { |
| int current = getWidth(children[i]); |
| if (current > width) |
| width = current; |
| } |
| return (width); |
| |
| } |
| |
| |
| /** |
| * Deregister the specified node, as well as all child nodes of this |
| * node, from our registry of the complete tree. If this node is not |
| * present, no action is taken. |
| * |
| * @param node The <code>TreeControlNode</code> to be deregistered |
| */ |
| void removeNode(TreeControlNode node) { |
| |
| synchronized (registry) { |
| TreeControlNode children[] = node.findChildren(); |
| for (int i = 0; i < children.length; i++) |
| removeNode(children[i]); |
| TreeControlNode parent = node.getParent(); |
| if (parent != null) { |
| parent.removeChild(node); |
| } |
| node.setParent(null); |
| node.setTree(null); |
| if (node == this.root) { |
| this.root = null; |
| } |
| registry.remove(node.getName()); |
| } |
| |
| } |
| |
| |
| } |
