TreeEvaluation.java

/**
* OLAT - Online Learning and Training<br>
* http://www.olat.org
* <p>
* Licensed under the Apache License, Version 2.0 (the "License"); <br>
* you may not use this file except in compliance with the License.<br>
* You may obtain a copy of the License at
* <p>
* http://www.apache.org/licenses/LICENSE-2.0
* <p>
* Unless required by applicable law or agreed to in writing,<br>
* software distributed under the License is distributed on an "AS IS" BASIS, <br>
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. <br>
* See the License for the specific language governing permissions and <br>
* limitations under the License.
* <p>
* Copyright (c) since 2004 at Multimedia- & E-Learning Services (MELS),<br>
* University of Zurich, Switzerland.
* <hr>
* <a href="http://www.openolat.org">
* OpenOLAT - Online Learning and Training</a><br>
* This file has been modified by the OpenOLAT community. Changes are licensed
* under the Apache 2.0 license as the original file.
*/

package org.olat.course.run.userview;

import java.util.HashMap;
import java.util.Map;

import org.olat.core.gui.components.tree.TreeNode;
import org.olat.course.nodes.CourseNode;

/**
 * Initial Date:  Feb 6, 2004
 * @author Felix Jost
 *
 */
public class TreeEvaluation {
	private final Map<CourseNode,TreeNode> courseToTree = new HashMap<CourseNode,TreeNode>();  // keys: coursenodes; values: treenodes

	public void cacheCourseToTreeNode(CourseNode cn, TreeNode tn) {
		courseToTree.put(cn, tn);
	}

	/**
	 * used to quickly know if a given coursenode is still in the generated treemodel, and if yes, 
	 * to fetch the treenode so we can reselect the user's selection even though we just built a new treemodel (which clears the selection of course)
	 * @param cn to courseNode to find
	 * @return null if the coursenode has no corresponding treenode in the newly built treemodel anymore (e.g. when the precondition evaluation changed so that the coursenode became invisible), or the TreeNode otherwise.
	 */
	public TreeNode getCorrespondingTreeNode(CourseNode cn) {
		return courseToTree.get(cn);
	}
	
	public TreeNode getCorrespondingTreeNode(String cnIdent) {
		TreeNode tn = null;
		for(Map.Entry<CourseNode, TreeNode> entry:courseToTree.entrySet()) {
			CourseNode cn = entry.getKey();
			if(cn.getIdent().equals(cnIdent)) {
				tn = entry.getValue();
				break;
			}
			
		}
		return tn;
	}
}