/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
/* $Id$ */
package org.apache.fop.fo;
import java.awt.geom.Point2D;
import java.util.HashMap;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.xml.sax.Attributes;
import org.xml.sax.Locator;
import org.apache.fop.apps.FOPException;
import org.apache.fop.datatypes.Length;
import org.apache.fop.util.ContentHandlerFactory.ObjectBuiltListener;
import org.apache.fop.util.XMLConstants;
/**
* Abstract class modelling generic, non-XSL-FO XML objects. Such objects are
* stored in a DOM.
*/
public abstract class XMLObj extends FONode implements ObjectBuiltListener {
// temp reference for attributes
private Attributes attr;
/** DOM element representing this node */
protected Element element;
/** DOM document containing this node */
protected Document doc;
/** Name of the node */
protected String name;
/**
* Base constructor
*
* @param parent {@link FONode} that is the parent of this object
*/
public XMLObj(FONode parent) {
super(parent);
}
/**
* {@inheritDoc}
* <br>Here, blocks XSL-FO's from having non-FO parents.
*/
protected void validateChildNode(Locator loc, String nsURI, String localName)
throws ValidationException {
if (FO_URI.equals(nsURI)) {
invalidChildError(loc, nsURI, localName);
}
}
/** {@inheritDoc} */
public void processNode(String elementName, Locator locator,
Attributes attlist, PropertyList propertyList) throws FOPException {
setLocator(locator);
name = elementName;
attr = attlist;
}
/**
* @return DOM document representing this foreign XML
*/
public Document getDOMDocument() {
return doc;
}
/**
* Returns the dimensions of the generated area in pts.
*
* @param view Point2D instance to receive the dimensions
* @return the requested dimensions in pts.
*/
public Point2D getDimension(Point2D view) {
return null;
}
/**
* Retrieve the intrinsic alignment-adjust of the child element.
*
* @return the intrinsic alignment-adjust.
*/
public Length getIntrinsicAlignmentAdjust() {
return null;
}
/** {@inheritDoc} */
public String getLocalName() {
return name;
}
private static HashMap ns = new HashMap();
static {
ns.put(XMLConstants.XLINK_PREFIX, XMLConstants.XLINK_NAMESPACE);
}
/**
* Add an element to the DOM document
* @param doc DOM document to which to add an element
* @param parent the parent element of the element that is being added
*/
public void addElement(Document doc, Element parent) {
this.doc = doc;
element = doc.createElementNS(getNamespaceURI(), name);
setAttributes(element, attr);
attr = null;
parent.appendChild(element);
}
private static void setAttributes(Element element, Attributes attr) {
for (int count = 0; count < attr.getLength(); count++) {
String rf = attr.getValue(count);
String qname = attr.getQName(count);
int idx = qname.indexOf(":");
if (idx == -1) {
element.setAttribute(qname, rf);
} else {
String pref = qname.substring(0, idx);
String tail = qname.substring(idx + 1);
if (pref.equals(XMLConstants.XMLNS_PREFIX)) {
ns.put(tail, rf);
} else {
element.setAttributeNS((String)ns.get(pref), tail, rf);
}
}
}
}
/**
* Add the top-level element to the DOM document
*
* @param doc DOM document
* @param svgRoot non-XSL-FO element to be added as the root of this document
*/
public void buildTopLevel(Document doc, Element svgRoot) {
// build up the info for the top level element
setAttributes(element, attr);
}
/**
* Create an empty DOM document
*
* @return DOM document
*/
public Document createBasicDocument() {
doc = null;
element = null;
try {
DocumentBuilderFactory fact = DocumentBuilderFactory.newInstance();
fact.setNamespaceAware(true);
doc = fact.newDocumentBuilder().newDocument();
Element el = doc.createElementNS(getNamespaceURI(), name);
doc.appendChild(el);
element = doc.getDocumentElement();
buildTopLevel(doc, element);
if (!element.hasAttributeNS(
XMLConstants.XMLNS_NAMESPACE_URI, XMLConstants.XMLNS_PREFIX)) {
element.setAttributeNS(XMLConstants.XMLNS_NAMESPACE_URI, XMLConstants.XMLNS_PREFIX,
getNamespaceURI());
}
} catch (Exception e) {
//TODO this is ugly because there may be subsequent failures like NPEs
log.error("Error while trying to instantiate a DOM Document", e);
}
return doc;
}
/** {@inheritDoc} */
protected void addChildNode(FONode child) {
if (child instanceof XMLObj) {
((XMLObj)child).addElement(doc, element);
} else {
// in theory someone might want to embed some defined
// xml (eg. fo) inside the foreign xml
// they could use a different namespace
log.debug("Invalid element: " + child.getName() + " inside foreign xml markup");
}
}
/** {@inheritDoc} */
protected void characters(char[] data, int start, int length,
PropertyList pList, Locator locator) throws FOPException {
super.characters(data, start, length, pList, locator);
String str = new String(data, start, length);
org.w3c.dom.Text text = doc.createTextNode(str);
element.appendChild(text);
}
/** {@inheritDoc} */
public void notifyObjectBuilt(Object obj) {
this.doc = (Document)obj;
this.element = this.doc.getDocumentElement();
}
}