/**
* 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) 1999-2007 at Multimedia- & E-Learning Services (MELS),<br>
* University of Zurich, Switzerland.
* <p>
*/
package org.olat.ims.cp.objects;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Vector;
import org.apache.log4j.Logger;
import org.dom4j.tree.DefaultElement;
import org.olat.core.logging.OLATRuntimeException;
import org.olat.core.util.CodeHelper;
import org.olat.ims.cp.CPCore;
import org.olat.ims.cp.CPManager;
/**
*
* Description:<br>
* This class represents an item-element of a IMS-manifest-file
*
* <P>
* Initial Date: 26.06.2008 <br>
*
* @author Sergio Trentini
*/
public class CPItem extends DefaultElement implements CPNode {
private String identifier;
private String identifierRef;
private String title;
private CPMetadata metadata;
private int position;
private DefaultElement parent;
private boolean visible;
private Vector<CPItem> items;
private Vector<String> errors;
private Logger log;
/**
* constructor is needed while building the datamodel-tree (parsing XML)
*
* @param me
*/
public CPItem(DefaultElement me, DefaultElement parent) {
super(me.getName());
items = new Vector<CPItem>();
errors = new Vector<String>();
log = Logger.getLogger(this.getClass());
// setAttributes(me.attributes());
setContent(me.content());
this.parent = parent;
this.identifier = me.attributeValue(CPCore.IDENTIFIER);
this.identifierRef = me.attributeValue(CPCore.IDENTIFIERREF, "");
String val = me.attributeValue(CPCore.ISVISIBLE, "true");
this.visible = (val != null && val.equals("true"));
}
/**
* Constructor is needed when generating a new Item (e.g. adding a new Item to
* the CP)
*/
public CPItem(String identifier) {
super(CPCore.ITEM);
log = Logger.getLogger(this.getClass());
visible = true;
this.identifier = identifier;
this.identifierRef = "";
items = new Vector<CPItem>();
errors = new Vector<String>();
}
public CPItem() {
this(CodeHelper.getGlobalForeverUniqueID());
}
/**
*
* @see org.olat.ims.cp.objects.CPNode#buildChildren()
*/
public void buildChildren() {
Iterator<DefaultElement> children = this.elementIterator();
// iterate through children
while (children.hasNext()) {
DefaultElement child = children.next();
if (child.getName().equals(CPCore.ITEM)) {
CPItem item = new CPItem(child, this);
item.buildChildren();
item.setPosition(items.size());
item.setParentElement(this);
items.add(item);
} else if (child.getName().equals(CPCore.TITLE)) {
title = child.getText();
} else if (child.getName().equals(CPCore.METADATA)) {
// TODO: implement LOM METADATA
metadata = new CPMetadata(child);
metadata.setParentElement(this);
}
}
this.clearContent();
validateElement();
}
/**
*
* @see org.olat.ims.cp.objects.CPNode#validateElement()
*/
public boolean validateElement() {
if (this.title == null || this.title.equals("")) {
errors.add("Invalid IMS-Manifest (missing \"title\" element in item " + this.identifier + " )");
return false;
}
if (this.identifier == null || this.identifier.equals("")) {
errors.add("Invalid IMS-Manifest (missing \"identifier\" attribute in item " + this.identifier + " )");
return false;
}
return true;
}
/**
*
* @see org.olat.ims.cp.objects.CPNode#getXML(java.lang.StringBuilder)
*/
public void buildDocument(DefaultElement parent) {
DefaultElement itemElement = new DefaultElement(CPCore.ITEM);
itemElement.addAttribute(CPCore.IDENTIFIER, identifier);
if (!identifierRef.equals("")) itemElement.addAttribute(CPCore.IDENTIFIERREF, identifierRef);
itemElement.addAttribute(CPCore.ISVISIBLE, isVisibleString());
if (metadata != null) {
metadata.buildDocument(itemElement);
}
DefaultElement titleElement = new DefaultElement(CPCore.TITLE);
titleElement.setText(title);
itemElement.add(titleElement);
for (Iterator<CPItem> itItem = items.iterator(); itItem.hasNext();) {
CPItem item = itItem.next();
item.buildDocument(itemElement);
}
parent.add(itemElement);
}
// *** CP manipulation ***
/**
* adds a new CPItem to the childrens-list of this item (inserts at the end)
*
* @param newItem the new CPItem to add
*/
public void addItem(CPItem newItem) {
newItem.setParentElement(this);
items.add(newItem);
newItem.setPosition(items.size() - 1);
log.info("addItem: added " + newItem.getIdentifier() + " to " + this.getIdentifier());
}
/**
* adds a new CPItem to the childrens-list of this item at position index
*
* @param newItem the new CPItem to add
* @param index position
*/
public void addItemAt(CPItem newItem, int index) {
newItem.setParentElement(this);
if (index > -1 && index <= items.size()) {
items.add(index, newItem);
newItem.setPosition(index);
} else {
addItem(newItem);
}
}
/**
* removes this item from the manifest
*/
public void removeFromManifest() {
if (parent.getClass().equals(CPItem.class)) {
CPItem p = (CPItem) parent;
p.removeChild(identifier);
} else if (parent.getClass().equals(CPOrganization.class)) {
CPOrganization p = (CPOrganization) parent;
p.removeChild(identifier);
}
}
/**
* removes a child <item>
*/
public void removeChild(String id) {
boolean removed = false;
for (Iterator<CPItem> itItem = items.iterator(); itItem.hasNext();) {
CPItem item = itItem.next();
if (item.getIdentifier().equals(id)) {
items.remove(item);
removed = true;
break;
}
}
if (!removed) { throw new OLATRuntimeException(CPOrganizations.class, "error while removing child: child-element with identifier \""
+ id + "\" not found!", new Exception()); }
}
/**
* @see org.dom4j.tree.DefaultElement#clone()
*/
public Object clone() {
CPItem copy = (CPItem) super.clone();
copy.setIdentifier(CodeHelper.getGlobalForeverUniqueID());
copy.setTitle(title + " copy");
// Since metadata cannot be edited for now we don't do a shallow
// copy. The parent remains the same as well, so does the logger.
// The subitems should be cloned though.
Vector<CPItem> clonedItems = (Vector<CPItem>) items.clone();
copy.items = clonedItems;
for (CPItem item : items) {
int index = items.indexOf(item);
CPItem clonedItem = (CPItem) item.clone();
clonedItem.setParentElement(copy);
clonedItems.set(index, clonedItem);
}
return copy;
}
/**
* Returns true, if item is visible
*
* @return boolean
*/
public boolean isVisible() {
return this.visible;
}
/**
* return "true" if item is visible "false" otherwise
*
* @return
*/
public String isVisibleString() {
if (this.isVisible()) return "true";
return "false";
}
// *** GETTERS ***
/**
* Returns the Item with the specified identifier Returns null if Item is not
* found
*
* @param identifier id
* @return CPItem or null
*/
public CPItem getItemByID(String id) {
Iterator<CPItem> it = items.iterator();
CPItem item;
while (it.hasNext()) {
item = it.next();
if (item.getIdentifier().equals(id)) { return item; }
}
// TODO: should it throw an exception, if no element with the given
// identifier is found ???
return null;
}
/**
* @see org.olat.ims.cp.objects.CPNode#getElementByIdentifier(java.lang.String)
*/
public DefaultElement getElementByIdentifier(String id) {
if (identifier.equals(id)) return this;
DefaultElement e;
for (Iterator<CPItem> it = items.iterator(); it.hasNext();) {
CPItem item = it.next();
e = item.getElementByIdentifier(id);
if (e != null) return e;
}
return null;
}
public String getTitle() {
return this.title;
}
public String getIdentifier() {
return this.identifier;
}
public String getIdentifierRef() {
return this.identifierRef;
}
public int getPosition() {
return position;
}
/**
* searches for the first item with a linked resource (identifierRef id not
* "") within the children items of this element if this element itself has a
* referenced resource, this item is returned if no resource is found, null is
* returned
*
* @return
*/
public CPItem getFirstItemWithResource() {
if (this.identifierRef != "") {
// this item has a linked resource
return this;
} else {
if (items.size() < 1) return null;
int i = 0;
CPItem it = items.elementAt(i);
while (it.identifierRef == "" && i < items.size()) {
it = items.elementAt(i);
i++;
}
if (it.identifierRef == "") { return null; }
return it;
}
}
public DefaultElement getParentElement() {
return parent;
}
public CPMetadata getMetadata() {
return metadata;
}
public Vector<CPItem> getItems() {
return items;
}
public List<String> getItemIdentifiers() {
List<String> ids = new ArrayList<String>();
for (CPItem item : items) {
ids.add(item.getIdentifier());
}
return ids;
}
/**
* returns a Vector which holds all the children and its subchildren etc.
*
* @return
*/
public Vector<CPItem> getAllItems() {
Vector<CPItem> allItems = new Vector<CPItem>();
allItems.addAll(this.getItems());
for (Iterator<CPItem> it = items.iterator(); it.hasNext();) {
CPItem item = it.next();
allItems.addAll(item.getAllItems());
}
return allItems;
}
public Iterator<CPItem> getItemIterator() {
return items.iterator();
}
/**
*
* @return
*/
String getLastError() {
if (errors.size() > 0) return errors.lastElement();
return null;
}
// *** SETTERS ***
public void setTitle(String title) {
this.title = title;
}
public void setIdentifier(String identifier) {
this.identifier = identifier;
}
public void setIdentifierRef(String identifierRef) {
this.identifierRef = identifierRef;
}
public void setVisible(boolean visible) {
this.visible = visible;
}
public void setPosition(int position) {
this.position = position;
}
public void setParentElement(DefaultElement parent) {
if (parent.getClass().equals(CPItem.class) || parent.getClass().equals(CPOrganization.class)) {
this.parent = parent;
} else {
throw new OLATRuntimeException(CPOrganizations.class, "error while setting parentElement in element \"" + this.identifier
+ "\". Only <item> or <organization> as parent-element allowed", new Exception());
}
}
public void setMetadata(CPMetadata md) {
metadata = md;
}
/**
* generates a new system-unique identifier and sets it
*/
public void setNewUniqueID() {
identifier = CodeHelper.getGlobalForeverUniqueID();
}
/**
* generates new system-unique ids for this element and all it's children
*
* @deprecated
*/
public void setNewUniqueIDrev() {
identifier = CodeHelper.getGlobalForeverUniqueID();
for (Iterator<CPItem> it = items.iterator(); it.hasNext();) {
CPItem item = it.next();
item.setNewUniqueIDrev();
}
}
}