/* -*- mode: java; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
Part of the Processing project - http://processing.org
Copyright (c) 2012 The Processing Foundation
Copyright (c) 2009-12 Ben Fry and Casey Reas
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation, version 2.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty
of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General
Public License along with this library; if not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330,
Boston, MA 02111-1307 USA
*/
package processing.data;
import java.io.*;
import javax.xml.parsers.*;
import org.w3c.dom.*;
import org.xml.sax.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.*;
import javax.xml.transform.stream.*;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;
import processing.core.PApplet;
/**
* This is the base class used for the Processing XML library,
* representing a single node of an XML tree.
*
* @webref data:composite
* @see PApplet#loadXML(String)
* @see PApplet#parseXML(String)
* @see PApplet#saveXML(XML, String)
*/
public class XML implements Serializable {
/** The internal representation, a DOM node. */
protected Node node;
// /** Cached locally because it's used often. */
// protected String name;
/** The parent element. */
protected XML parent;
/** Child elements, once loaded. */
protected XML[] children;
/**
* @nowebref
*/
protected XML() { }
// /**
// * Begin parsing XML data passed in from a PApplet. This code
// * wraps exception handling, for more advanced exception handling,
// * use the constructor that takes a Reader or InputStream.
// *
// * @throws SAXException
// * @throws ParserConfigurationException
// * @throws IOException
// */
// public XML(PApplet parent, String filename) throws IOException, ParserConfigurationException, SAXException {
// this(parent.createReader(filename));
// }
/**
* Advanced users only; use loadXML() in PApplet. This is not a supported
* function and is subject to change. It is available simply for users that
* would like to handle the exceptions in a particular way.
*
* @nowebref
*/
public XML(File file) throws IOException, ParserConfigurationException, SAXException {
this(file, null);
}
/**
* Advanced users only; use loadXML() in PApplet.
*
* @nowebref
*/
public XML(File file, String options) throws IOException, ParserConfigurationException, SAXException {
this(PApplet.createReader(file), options);
}
/**
* @nowebref
*/
public XML(InputStream input) throws IOException, ParserConfigurationException, SAXException {
this(input, null);
}
/**
* Unlike the loadXML() method in PApplet, this version works with files
* that are not in UTF-8 format.
*
* @nowebref
*/
public XML(InputStream input, String options) throws IOException, ParserConfigurationException, SAXException {
//this(PApplet.createReader(input), options); // won't handle non-UTF8
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
try {
// Prevent 503 errors from www.w3.org
factory.setAttribute("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);
} catch (IllegalArgumentException e) {
// ignore this; Android doesn't like it
}
factory.setExpandEntityReferences(false);
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse(new InputSource(input));
node = document.getDocumentElement();
}
/**
* Advanced users only; use loadXML() in PApplet.
*
* @nowebref
*/
public XML(Reader reader) throws IOException, ParserConfigurationException, SAXException {
this(reader, null);
}
/**
* Advanced users only; use loadXML() in PApplet.
*
* Added extra code to handle \u2028 (Unicode NLF), which is sometimes
* inserted by web browsers (Safari?) and not distinguishable from a "real"
* LF (or CRLF) in some text editors (i.e. TextEdit on OS X). Only doing
* this for XML (and not all Reader objects) because LFs are essential.
* https://github.com/processing/processing/issues/2100
*
* @nowebref
*/
public XML(final Reader reader, String options) throws IOException, ParserConfigurationException, SAXException {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
// Prevent 503 errors from www.w3.org
try {
factory.setAttribute("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);
} catch (IllegalArgumentException e) {
// ignore this; Android doesn't like it
}
// without a validating DTD, this doesn't do anything since it doesn't know what is ignorable
// factory.setIgnoringElementContentWhitespace(true);
factory.setExpandEntityReferences(false);
// factory.setExpandEntityReferences(true);
// factory.setCoalescing(true);
// builderFactory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
DocumentBuilder builder = factory.newDocumentBuilder();
// builder.setEntityResolver()
// SAXParserFactory spf = SAXParserFactory.newInstance();
// spf.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
// SAXParser p = spf.newSAXParser();
// builder = DocumentBuilderFactory.newDocumentBuilder();
// builder = new SAXBuilder();
// builder.setValidation(validating);
Document document = builder.parse(new InputSource(new Reader() {
@Override
public int read(char[] cbuf, int off, int len) throws IOException {
int count = reader.read(cbuf, off, len);
for (int i = 0; i < count; i++) {
if (cbuf[off+i] == '\u2028') {
cbuf[off+i] = '\n';
}
}
return count;
}
@Override
public void close() throws IOException {
reader.close();
}
}));
node = document.getDocumentElement();
}
/**
* @param name creates a node with this name
*
*/
public XML(String name) {
try {
// TODO is there a more efficient way of doing this? wow.
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.newDocument();
node = document.createElement(name);
this.parent = null;
} catch (ParserConfigurationException pce) {
throw new RuntimeException(pce);
}
}
/**
* @nowebref
*/
protected XML(XML parent, Node node) {
this.node = node;
this.parent = parent;
for (String attr : parent.listAttributes()) {
if (attr.startsWith("xmlns")) {
// Copy namespace attributes to the kids, otherwise this XML
// can no longer be printed (or manipulated in most ways).
// Only do this when it's an Element, otherwise it's trying to set
// attributes on text notes (interstitial content).
if (node instanceof Element) {
setString(attr, parent.getString(attr));
}
}
}
}
/**
* @webref xml:method
* @brief Converts String content to an XML object
* @param data the content to be parsed as XML
* @return an XML object, or null
* @throws SAXException
* @throws ParserConfigurationException
* @throws IOException
* @nowebref
*/
static public XML parse(String data) throws IOException, ParserConfigurationException, SAXException {
return XML.parse(data, null);
}
/**
* @nowebref
*/
static public XML parse(String data, String options) throws IOException, ParserConfigurationException, SAXException {
return new XML(new StringReader(data), null);
}
// protected boolean save(OutputStream output) {
// return write(PApplet.createWriter(output));
// }
public boolean save(File file) {
return save(file, null);
}
public boolean save(File file, String options) {
PrintWriter writer = PApplet.createWriter(file);
boolean result = write(writer);
writer.flush();
writer.close();
return result;
}
// Sends this object and its kids to a Writer with an indent of 2 spaces,
// including the declaration at the top so that the output will be valid XML.
public boolean write(PrintWriter output) {
output.print(format(2));
output.flush();
return true;
}
/**
* Returns the parent element. This method returns null for the root
* element.
*
* @webref xml:method
* @brief Gets a copy of the element's parent
*/
public XML getParent() {
return this.parent;
}
/**
* Internal function; not included in reference.
*/
protected Object getNative() {
return node;
}
/**
* Returns the full name (i.e. the name including an eventual namespace
* prefix) of the element.
*
* @webref xml:method
* @brief Gets the element's full name
* @return the name, or null if the element only contains #PCDATA.
*/
public String getName() {
// return name;
return node.getNodeName();
}
/**
* @webref xml:method
* @brief Sets the element's name
*/
public void setName(String newName) {
Document document = node.getOwnerDocument();
node = document.renameNode(node, null, newName);
// name = node.getNodeName();
}
/**
* Returns the name of the element (without namespace prefix).
*
* Internal function; not included in reference.
*/
public String getLocalName() {
return node.getLocalName();
}
/**
* Honey, can you just check on the kids? Thanks.
*
* Internal function; not included in reference.
*/
protected void checkChildren() {
if (children == null) {
NodeList kids = node.getChildNodes();
int childCount = kids.getLength();
children = new XML[childCount];
for (int i = 0; i < childCount; i++) {
children[i] = new XML(this, kids.item(i));
}
}
}
/**
* Returns the number of children.
*
* @webref xml:method
* @brief Returns the element's number of children
* @return the count.
*/
public int getChildCount() {
checkChildren();
return children.length;
}
/**
* Returns a boolean of whether or not there are children.
*
* @webref xml:method
* @brief Checks whether or not an element has any children
*/
public boolean hasChildren() {
checkChildren();
return children.length > 0;
}
/**
* Put the names of all children into an array. Same as looping through
* each child and calling getName() on each XMLElement.
*
* @webref xml:method
* @brief Returns the names of all children as an array
*/
public String[] listChildren() {
// NodeList children = node.getChildNodes();
// int childCount = children.getLength();
// String[] outgoing = new String[childCount];
// for (int i = 0; i < childCount; i++) {
// Node kid = children.item(i);
// if (kid.getNodeType() == Node.ELEMENT_NODE) {
// outgoing[i] = kid.getNodeName();
// } // otherwise just leave him null
// }
checkChildren();
String[] outgoing = new String[children.length];
for (int i = 0; i < children.length; i++) {
outgoing[i] = children[i].getName();
}
return outgoing;
}
/**
* Returns an array containing all the child elements.
*
* @webref xml:method
* @brief Returns an array containing all child elements
*/
public XML[] getChildren() {
// NodeList children = node.getChildNodes();
// int childCount = children.getLength();
// XMLElement[] kids = new XMLElement[childCount];
// for (int i = 0; i < childCount; i++) {
// Node kid = children.item(i);
// kids[i] = new XMLElement(this, kid);
// }
// return kids;
checkChildren();
return children;
}
/**
* Quick accessor for an element at a particular index.
*
* @nowebref
*/
public XML getChild(int index) {
checkChildren();
return children[index];
}
/**
* Get a child by its name or path.
*
* @webref xml:method
* @brief Returns the child element with the specified index value or path
* @param name element name or path/to/element
* @return the first matching element or null if no match
*/
public XML getChild(String name) {
if (name.length() > 0 && name.charAt(0) == '/') {
throw new IllegalArgumentException("getChild() should not begin with a slash");
}
if (name.indexOf('/') != -1) {
return getChildRecursive(PApplet.split(name, '/'), 0);
}
int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
XML kid = getChild(i);
String kidName = kid.getName();
if (kidName != null && kidName.equals(name)) {
return kid;
}
}
return null;
}
/**
* Internal helper function for getChild(String).
*
* @param items result of splitting the query on slashes
* @param offset where in the items[] array we're currently looking
* @return matching element or null if no match
* @author processing.org
*/
protected XML getChildRecursive(String[] items, int offset) {
// if it's a number, do an index instead
if (Character.isDigit(items[offset].charAt(0))) {
XML kid = getChild(Integer.parseInt(items[offset]));
if (offset == items.length-1) {
return kid;
} else {
return kid.getChildRecursive(items, offset+1);
}
}
int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
XML kid = getChild(i);
String kidName = kid.getName();
if (kidName != null && kidName.equals(items[offset])) {
if (offset == items.length-1) {
return kid;
} else {
return kid.getChildRecursive(items, offset+1);
}
}
}
return null;
}
/**
* Get any children that match this name or path. Similar to getChild(),
* but will grab multiple matches rather than only the first.
*
* @param name element name or path/to/element
* @return array of child elements that match
* @author processing.org
*/
public XML[] getChildren(String name) {
if (name.length() > 0 && name.charAt(0) == '/') {
throw new IllegalArgumentException("getChildren() should not begin with a slash");
}
if (name.indexOf('/') != -1) {
return getChildrenRecursive(PApplet.split(name, '/'), 0);
}
// if it's a number, do an index instead
// (returns a single element array, since this will be a single match
if (Character.isDigit(name.charAt(0))) {
return new XML[] { getChild(Integer.parseInt(name)) };
}
int childCount = getChildCount();
XML[] matches = new XML[childCount];
int matchCount = 0;
for (int i = 0; i < childCount; i++) {
XML kid = getChild(i);
String kidName = kid.getName();
if (kidName != null && kidName.equals(name)) {
matches[matchCount++] = kid;
}
}
return (XML[]) PApplet.subset(matches, 0, matchCount);
}
protected XML[] getChildrenRecursive(String[] items, int offset) {
if (offset == items.length-1) {
return getChildren(items[offset]);
}
XML[] matches = getChildren(items[offset]);
XML[] outgoing = new XML[0];
for (int i = 0; i < matches.length; i++) {
XML[] kidMatches = matches[i].getChildrenRecursive(items, offset+1);
outgoing = (XML[]) PApplet.concat(outgoing, kidMatches);
}
return outgoing;
}
/**
* @webref xml:method
* @brief Appends a new child to the element
*/
public XML addChild(String tag) {
Document document = node.getOwnerDocument();
Node newChild = document.createElement(tag);
return appendChild(newChild);
}
public XML addChild(XML child) {
Document document = node.getOwnerDocument();
Node newChild = document.importNode((Node) child.getNative(), true);
return appendChild(newChild);
}
/** Internal handler to add the node structure. */
protected XML appendChild(Node newNode) {
node.appendChild(newNode);
XML newbie = new XML(this, newNode);
if (children != null) {
children = (XML[]) PApplet.concat(children, new XML[] { newbie });
}
return newbie;
}
/**
* @webref xml:method
* @brief Removes the specified child
*/
public void removeChild(XML kid) {
node.removeChild(kid.node);
children = null; // TODO not efficient
}
/**
* Removes whitespace nodes.
* Those whitespace nodes are required to reconstruct the original XML's spacing and indentation.
* If you call this and use saveXML() your original spacing will be gone.
*
* @nowebref
* @brief Removes whitespace nodes
*/
public void trim() {
try {
XPathFactory xpathFactory = XPathFactory.newInstance();
XPathExpression xpathExp =
xpathFactory.newXPath().compile("//text()[normalize-space(.) = '']");
NodeList emptyTextNodes = (NodeList)
xpathExp.evaluate(node, XPathConstants.NODESET);
// Remove each empty text node from document.
for (int i = 0; i < emptyTextNodes.getLength(); i++) {
Node emptyTextNode = emptyTextNodes.item(i);
emptyTextNode.getParentNode().removeChild(emptyTextNode);
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
// /** Remove whitespace nodes. */
// public void trim() {
////// public static boolean isWhitespace(XML xml) {
////// if (xml.node.getNodeType() != Node.TEXT_NODE)
////// return false;
////// Matcher m = whitespace.matcher(xml.node.getNodeValue());
////// return m.matches();
////// }
//// trim(this);
//// }
//
// checkChildren();
// int index = 0;
// for (int i = 0; i < children.length; i++) {
// if (i != index) {
// children[index] = children[i];
// }
// Node childNode = (Node) children[i].getNative();
// if (childNode.getNodeType() != Node.TEXT_NODE ||
// children[i].getContent().trim().length() > 0) {
// children[i].trim();
// index++;
// }
// }
// if (index != children.length) {
// children = (XML[]) PApplet.subset(children, 0, index);
// }
//
// // possibility, but would have to re-parse the object
//// helpdesk.objects.com.au/java/how-do-i-remove-whitespace-from-an-xml-document
//// TransformerFactory factory = TransformerFactory.newInstance();
//// Transformer transformer = factory.newTransformer(new StreamSource("strip-space.xsl"));
//// DOMSource source = new DOMSource(document);
//// StreamResult result = new StreamResult(System.out);
//// transformer.transform(source, result);
//
////