org.openide.xml.XMLUtil Maven / Gradle / Ivy
/*
* 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.
*/
package org.openide.xml;
import java.io.ByteArrayInputStream;
import java.io.CharConversionException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.StringReader;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.Map;
import java.util.Set;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.FactoryConfigurationError;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.Validator;
import org.openide.util.Exceptions;
import org.w3c.dom.Attr;
import org.w3c.dom.CDATASection;
import org.w3c.dom.DOMException;
import org.w3c.dom.DOMImplementation;
import org.w3c.dom.Document;
import org.w3c.dom.DocumentType;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.XMLReader;
/**
* Utility class collecting library methods related to XML processing.
*/
public final class XMLUtil extends Object {
/*
public static String toCDATA(String val) throws IOException {
}
*/
private static final char[] DEC2HEX = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
/** Forbids creating new XMLUtil */
private XMLUtil() {
}
// ~~~~~~~~~~~~~~~~~~~~~ SAX related ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/** Create a simple parser.
* @return createXMLReader(false, false)
*/
public static XMLReader createXMLReader() throws SAXException {
return createXMLReader(false, false);
}
/** Create a simple parser, possibly validating.
* @param validate if true, a validating parser is returned
* @return createXMLReader(validate, false)
*/
public static XMLReader createXMLReader(boolean validate)
throws SAXException {
return createXMLReader(validate, false);
}
private static SAXParserFactory[][] saxes = new SAXParserFactory[2][2];
/** Creates a SAX parser.
*
* See {@link #parse} for hints on setting an entity resolver.
*
* @param validate if true, a validating parser is returned
* @param namespaceAware if true, a namespace aware parser is returned
*
* @throws FactoryConfigurationError Application developers should never need to directly catch errors of this type.
* @throws SAXException if a parser fulfilling given parameters can not be created
*
* @return XMLReader configured according to passed parameters
*/
public static synchronized XMLReader createXMLReader(boolean validate, boolean namespaceAware)
throws SAXException {
SAXParserFactory factory = saxes[validate ? 0 : 1][namespaceAware ? 0 : 1];
if (factory == null) {
try {
factory = SAXParserFactory.newInstance();
} catch (FactoryConfigurationError err) {
Exceptions.attachMessage(
err,
"Info about thread context classloader: " + // NOI18N
Thread.currentThread().getContextClassLoader()
);
throw err;
}
factory.setValidating(validate);
factory.setNamespaceAware(namespaceAware);
saxes[validate ? 0 : 1][namespaceAware ? 0 : 1] = factory;
}
try {
return factory.newSAXParser().getXMLReader();
} catch (ParserConfigurationException ex) {
throw new SAXException("Cannot create parser satisfying configuration parameters", ex); //NOI18N
}
}
// ~~~~~~~~~~~~~~~~~~~~~ DOM related ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* Creates an empty DOM document. E.g.:
*
* Document doc = createDocument("book", null, null, null);
*
* creates new DOM of a well-formed document with root element named book.
*
* @param rootQName qualified name of root element. e.g. myroot or ns:myroot
* @param namespaceURI URI of root element namespace or null
* @param doctypePublicID public ID of DOCTYPE or null
* @param doctypeSystemID system ID of DOCTYPE or null if no DOCTYPE
* required and doctypePublicID is also null
*
* @throws DOMException if new DOM with passed parameters can not be created
* @throws FactoryConfigurationError Application developers should never need to directly catch errors of this type.
*
* @return new DOM Document
*/
public static Document createDocument(
String rootQName, String namespaceURI, String doctypePublicID, String doctypeSystemID
) throws DOMException {
DOMImplementation impl = getDOMImplementation();
if ((doctypePublicID != null) && (doctypeSystemID == null)) {
throw new IllegalArgumentException("System ID cannot be null if public ID specified. "); //NOI18N
}
DocumentType dtd = null;
if (doctypeSystemID != null) {
dtd = impl.createDocumentType(rootQName, doctypePublicID, doctypeSystemID);
}
return impl.createDocument(namespaceURI, rootQName, dtd);
}
/**
* Obtains DOMImpementaton interface providing a number of methods for performing
* operations that are independent of any particular DOM instance.
*
* @throw DOMException NOT_SUPPORTED_ERR if cannot get DOMImplementation
* @throw FactoryConfigurationError Application developers should never need to directly catch errors of this type.
*
* @return DOMImplementation implementation
*/
private static DOMImplementation getDOMImplementation()
throws DOMException { //can be made public
DocumentBuilderFactory factory = getFactory(false, false);
try {
return factory.newDocumentBuilder().getDOMImplementation();
} catch (ParserConfigurationException ex) {
throw new DOMException(
DOMException.NOT_SUPPORTED_ERR, "Cannot create parser satisfying configuration parameters"
); //NOI18N
} catch (RuntimeException e) {
// E.g. #36578, IllegalArgumentException. Try to recover gracefully.
throw (DOMException) new DOMException(DOMException.NOT_SUPPORTED_ERR, e.toString()).initCause(e);
}
}
private static DocumentBuilderFactory[][] doms = new DocumentBuilderFactory[2][2];
private static synchronized DocumentBuilderFactory getFactory(boolean validate, boolean namespaceAware) {
DocumentBuilderFactory factory = doms[validate ? 0 : 1][namespaceAware ? 0 : 1];
if (factory == null) {
factory = DocumentBuilderFactory.newInstance();
factory.setValidating(validate);
factory.setNamespaceAware(namespaceAware);
doms[validate ? 0 : 1][namespaceAware ? 0 : 1] = factory;
}
return factory;
}
/**
* Parses an XML document into a DOM tree.
*
*
*
* Remember that when parsing XML files you often want to set an explicit
* entity resolver. For example, consider a file such as this:
*
*
* <?xml version="1.0" encoding="UTF-8"?>
* <!DOCTYPE root PUBLIC "-//NetBeans//DTD Foo 1.0//EN" "http://www.netbeans.org/dtds/foo-1_0.dtd">
* <root/>
*
*
* If you parse this with a null entity resolver, or you use the
* default resolver ({@link EntityCatalog#getDefault}) but do not do
* anything special with this DTD, you will probably find the parse
* blocking to make a network connection even when you are not
* validating. That is because DTDs can be used to define
* entities and other XML oddities, and are not a pure constraint
* language like Schema or RELAX-NG.
*
* There are three basic ways to avoid the network connection.
*
*
*
* Register the DTD. This is generally the best thing to do. See
* {@link EntityCatalog}'s documentation for details, but for example
* in your layer use:
*
*
* <filesystem>
* <folder name="xml">
* <folder name="entities">
* <folder name="NetBeans">
* <file name="DTD_Foo_1_0"
* url="resources/foo-1_0.dtd">
* <attr name="hint.originalPublicID"
* stringvalue="-//NetBeans//DTD Foo 1.0//EN"/>
* </file>
* </folder>
* </folder>
* </folder>
* </filesystem>
*
*
* Now the default system entity catalog will resolve the public ID
* to the local copy in your module, not the network copy.
* Additionally, anyone who mounts the "NetBeans Catalog" in the XML
* Entity Catalogs node in the Runtime tab will be able to use your
* local copy of the DTD automatically, for validation, code
* completion, etc. (The network URL should really exist, though, for
* the benefit of other tools!)
You can also set an explicit entity resolver which maps that
* particular public ID to some local copy of the DTD, if you do not
* want to register it globally in the system for some reason. If
* handed other public IDs, just return null to indicate that the
* system ID should be loaded.
In some cases where XML parsing is very
* performance-sensitive, and you know that you do not need validation
* and furthermore that the DTD defines no infoset (there are no
* entity or character definitions, etc.), you can speed up the parse.
* Turn off validation, but also supply a custom entity resolver that
* does not even bother to load the DTD at all:
*
*
* public InputSource resolveEntity(String pubid, String sysid)
* throws SAXException, IOException {
* if (pubid.equals("-//NetBeans//DTD Foo 1.0//EN")) {
* return new InputSource(new ByteArrayInputStream(new byte[0]));
* } else {
* return EntityCatalog.getDefault().resolveEntity(pubid, sysid);
* }
* }
*
*
*
*
* @param input a parser input (for URL users use: new InputSource(url.toString())
* @param validate if true validating parser is used
* @param namespaceAware if true DOM is created by namespace aware parser
* @param errorHandler a error handler to notify about exception (such as {@link #defaultErrorHandler}) or null
* @param entityResolver SAX entity resolver (such as {@link EntityCatalog#getDefault}) or null
*
* @throws IOException if an I/O problem during parsing occurs
* @throws SAXException is thrown if a parser error occurs
* @throws FactoryConfigurationError Application developers should never need to directly catch errors of this type.
*
* @return document representing given input
*/
public static Document parse(
InputSource input, boolean validate, boolean namespaceAware, ErrorHandler errorHandler,
EntityResolver entityResolver
) throws IOException, SAXException {
DocumentBuilder builder = null;
DocumentBuilderFactory factory = getFactory(validate, namespaceAware);
try {
builder = factory.newDocumentBuilder();
} catch (ParserConfigurationException ex) {
throw new SAXException("Cannot create parser satisfying configuration parameters", ex); //NOI18N
}
if (errorHandler != null) {
builder.setErrorHandler(errorHandler);
}
if (entityResolver != null) {
builder.setEntityResolver(entityResolver);
}
return builder.parse(input);
}
/**
* Identity transformation in XSLT with indentation added.
* Just using the identity transform and calling
* t.setOutputProperty(OutputKeys.INDENT, "yes");
* t.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
* does not work currently.
* You really have to use this bogus stylesheet.
* @see "JDK bug #5064280"
*/
private static final String IDENTITY_XSLT_WITH_INDENT =
"" + // NOI18N
"" + // NOI18N
"" + // NOI18N
" " + // NOI18N
" " + // NOI18N
" "; // NOI18N
/** Workaround for JAXP bug 7150637 / XALANJ-1497. */
private static final String ORACLE_IS_STANDALONE = "http://www.oracle.com/xml/is-standalone";
/**
* Writes a DOM document to a stream.
* The precise output format is not guaranteed but this method will attempt to indent it sensibly.
*
* Important: There might be some problems with
* <![CDATA[ ]]> sections in the DOM tree you pass into this method. Specifically,
* some CDATA sections my not be written as CDATA section or may be merged with
* other CDATA section at the same level. Also if plain text nodes are mixed with
* CDATA sections at the same level all text is likely to end up in one big CDATA section.
*
* For nodes that only have one CDATA section this method should work fine.
*
*
* @param doc DOM document to be written
* @param out data sink
* @param enc XML-defined encoding name (e.g. "UTF-8")
* @throws IOException if JAXP fails or the stream cannot be written to
*/
public static void write(Document doc, OutputStream out, String enc) throws IOException {
if (enc == null) {
throw new NullPointerException("You must set an encoding; use \"UTF-8\" unless you have a good reason not to!"); // NOI18N
}
Document doc2 = normalize(doc);
ClassLoader orig = Thread.currentThread().getContextClassLoader();
Thread.currentThread().setContextClassLoader(AccessController.doPrivileged(new PrivilegedAction() { // #195921
@Override public ClassLoader run() {
return new ClassLoader(ClassLoader.getSystemClassLoader().getParent()) {
@Override public InputStream getResourceAsStream(String name) {
if (name.startsWith("META-INF/services/")) {
return new ByteArrayInputStream(new byte[0]); // JAXP #6723276
}
return super.getResourceAsStream(name);
}
};
}
}));
try {
TransformerFactory tf = TransformerFactory.newInstance();
Transformer t = tf.newTransformer(
new StreamSource(new StringReader(IDENTITY_XSLT_WITH_INDENT)));
DocumentType dt = doc2.getDoctype();
if (dt != null) {
String pub = dt.getPublicId();
if (pub != null) {
t.setOutputProperty(OutputKeys.DOCTYPE_PUBLIC, pub);
}
String sys = dt.getSystemId();
if (sys != null) {
t.setOutputProperty(OutputKeys.DOCTYPE_SYSTEM, sys);
}
}
t.setOutputProperty(OutputKeys.ENCODING, enc);
try {
t.setOutputProperty(ORACLE_IS_STANDALONE, "yes");
} catch (IllegalArgumentException x) {
// fine, introduced in JDK 7u4
}
// See #123816
Set cdataQNames = new HashSet();
collectCDATASections(doc2, cdataQNames);
if (cdataQNames.size() > 0) {
StringBuilder cdataSections = new StringBuilder();
for(String s : cdataQNames) {
cdataSections.append(s).append(' '); //NOI18N
}
t.setOutputProperty(OutputKeys.CDATA_SECTION_ELEMENTS, cdataSections.toString());
}
Source source = new DOMSource(doc2);
Result result = new StreamResult(out);
t.transform(source, result);
} catch (Exception e) {
throw new IOException(e);
} finally {
Thread.currentThread().setContextClassLoader(orig);
}
}
private static void collectCDATASections(Node node, Set cdataQNames) {
if (node instanceof CDATASection) {
Node parent = node.getParentNode();
if (parent != null) {
String uri = parent.getNamespaceURI();
if (uri != null) {
cdataQNames.add("{" + uri + "}" + parent.getNodeName()); //NOI18N
} else {
cdataQNames.add(parent.getNodeName());
}
}
}
NodeList children = node.getChildNodes();
for(int i = 0; i < children.getLength(); i++) {
collectCDATASections(children.item(i), cdataQNames);
}
}
/**
* Check whether a DOM tree is valid according to a schema.
* Example of usage:
*
* Element fragment = ...;
* SchemaFactory f = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
* Schema s = f.newSchema(This.class.getResource("something.xsd"));
* try {
* XMLUtil.validate(fragment, s);
* // valid
* } catch (SAXException x) {
* // invalid
* }
*
* @param data a DOM tree
* @param schema a parsed schema
* @throws SAXException if validation failed
* @since org.openide.util 7.17
*/
public static void validate(Element data, Schema schema) throws SAXException {
Validator v = schema.newValidator();
final SAXException[] error = {null};
v.setErrorHandler(new ErrorHandler() {
public @Override void warning(SAXParseException x) throws SAXException {}
public @Override void error(SAXParseException x) throws SAXException {
// Just rethrowing it is bad because it will also print it to stderr.
error[0] = x;
}
public @Override void fatalError(SAXParseException x) throws SAXException {
error[0] = x;
}
});
try {
v.validate(new DOMSource(fixupAttrs(data)));
} catch (IOException x) {
assert false : x;
}
if (error[0] != null) {
throw error[0];
}
}
private static Element fixupAttrs(Element root) { // #140905
// #6529766/#6531160: some versions of JAXP reject attributes set using setAttribute
// (rather than setAttributeNS) even though the schema calls for no-NS attrs!
// JDK 5 is fine; JDK 6 broken; JDK 6u2+ fixed
// #146081: xml:base attributes mess up validation too.
Element copy = (Element) root.cloneNode(true);
fixupAttrsSingle(copy);
NodeList nl = copy.getElementsByTagName("*"); // NOI18N
for (int i = 0; i < nl.getLength(); i++) {
fixupAttrsSingle((Element) nl.item(i));
}
return copy;
}
private static void fixupAttrsSingle(Element e) throws DOMException {
removeXmlBase(e);
Map replace = new HashMap();
NamedNodeMap attrs = e.getAttributes();
for (int j = 0; j < attrs.getLength(); j++) {
Attr attr = (Attr) attrs.item(j);
if (attr.getNamespaceURI() == null && !attr.getName().equals("xmlns")) { // NOI18N
replace.put(attr.getName(), attr.getValue());
}
}
for (Map.Entry entry : replace.entrySet()) {
e.removeAttribute(entry.getKey());
e.setAttributeNS(null, entry.getKey(), entry.getValue());
}
}
private static void removeXmlBase(Element e) {
e.removeAttributeNS("http://www.w3.org/XML/1998/namespace", "base"); // NOI18N
e.removeAttribute("xml:base"); // NOI18N
}
/**
* Escape passed string as XML attibute value
* (<, &, ' and "
* will be escaped.
* Note: An XML processor returns normalized value that can be different.
*
* @param val a string to be escaped
*
* @return escaped value
* @throws CharConversionException if val contains an improper XML character
*
* @since 1.40
*/
public static String toAttributeValue(String val) throws CharConversionException {
if (val == null) {
throw new CharConversionException("null"); // NOI18N
}
if (checkAttributeCharacters(val)) {
return val;
}
StringBuilder buf = new StringBuilder();
for (int i = 0; i < val.length(); i++) {
char ch = val.charAt(i);
if ('<' == ch) {
buf.append("<");
continue;
} else if ('&' == ch) {
buf.append("&");
continue;
} else if ('\'' == ch) {
buf.append("'");
continue;
} else if ('"' == ch) {
buf.append(""");
continue;
}
buf.append(ch);
}
return buf.toString();
}
/**
* Escape passed string as XML element content (<,
* & and > in ]]> sequences).
*
* @param val a string to be escaped
*
* @return escaped value
* @throws CharConversionException if val contains an improper XML character
*
* @since 1.40
*/
public static String toElementContent(String val) throws CharConversionException {
if (val == null) {
throw new CharConversionException("null"); // NOI18N
}
if (checkContentCharacters(val)) {
return val;
}
StringBuilder buf = new StringBuilder();
for (int i = 0; i < val.length(); i++) {
char ch = val.charAt(i);
if ('<' == ch) {
buf.append("<");
continue;
} else if ('&' == ch) {
buf.append("&");
continue;
} else if (('>' == ch) && (i > 1) && (val.charAt(i - 2) == ']') && (val.charAt(i - 1) == ']')) {
buf.append(">");
continue;
}
buf.append(ch);
}
return buf.toString();
}
/**
* Can be used to encode values that contain invalid XML characters.
* At SAX parser end must be used pair method to get original value.
*
* @param val data to be converted
* @param start offset
* @param len count
*
* @since 1.29
*/
public static String toHex(byte[] val, int start, int len) {
StringBuilder buf = new StringBuilder();
for (int i = 0; i < len; i++) {
byte b = val[start + i];
buf.append(DEC2HEX[(b & 0xf0) >> 4]);
buf.append(DEC2HEX[b & 0x0f]);
}
return buf.toString();
}
/**
* Decodes data encoded using {@link #toHex(byte[],int,int) toHex}.
*
* @param hex data to be converted
* @param start offset
* @param len count
*
* @throws IOException if input does not represent hex encoded value
*
* @since 1.29
*/
public static byte[] fromHex(char[] hex, int start, int len)
throws IOException {
if (hex == null) {
throw new IOException("null");
}
int i = hex.length;
if ((i % 2) != 0) {
throw new IOException("odd length");
}
byte[] magic = new byte[i / 2];
for (; i > 0; i -= 2) {
String g = new String(hex, i - 2, 2);
try {
magic[(i / 2) - 1] = (byte) Integer.parseInt(g, 16);
} catch (NumberFormatException ex) {
throw new IOException(ex.getLocalizedMessage());
}
}
return magic;
}
/**
* Check if all passed characters match XML expression [2].
* @return true if no escaping necessary
* @throws CharConversionException if contains invalid chars
*/
private static boolean checkAttributeCharacters(String chars)
throws CharConversionException {
boolean escape = false;
for (int i = 0; i < chars.length(); i++) {
char ch = chars.charAt(i);
if (((int) ch) <= 93) { // we are UNICODE ']'
switch (ch) {
case 0x9:
case 0xA:
case 0xD:
continue;
case '\'':
case '"':
case '<':
case '&':
escape = true;
continue;
default:
if (((int) ch) < 0x20) {
throw new CharConversionException("Invalid XML character &#" + ((int) ch) + ";.");
}
}
}
}
return escape == false;
}
/**
* Check if all passed characters match XML expression [2].
* @return true if no escaping necessary
* @throws CharConversionException if contains invalid chars
*/
private static boolean checkContentCharacters(String chars)
throws CharConversionException {
boolean escape = false;
for (int i = 0; i < chars.length(); i++) {
char ch = chars.charAt(i);
if (((int) ch) <= 93) { // we are UNICODE ']'
switch (ch) {
case 0x9:
case 0xA:
case 0xD:
continue;
case '>': // only ]]> is dangerous
if (escape) {
continue;
}
escape = (i > 0) && (chars.charAt(i - 1) == ']');
continue;
case '<':
case '&':
escape = true;
continue;
default:
if (((int) ch) < 0x20) {
throw new CharConversionException("Invalid XML character &#" + ((int) ch) + ";.");
}
}
}
}
return escape == false;
}
/**
* Try to normalize a document by removing nonsignificant whitespace.
* @see "#62006"
*/
private static Document normalize(Document orig) throws IOException {
DocumentBuilder builder = null;
DocumentBuilderFactory factory = getFactory(false, false);
try {
builder = factory.newDocumentBuilder();
} catch (ParserConfigurationException e) {
throw new IOException("Cannot create parser satisfying configuration parameters: " + e, e); //NOI18N
}
DocumentType doctype = null;
NodeList nl = orig.getChildNodes();
for (int i = 0; i < nl.getLength(); i++) {
if (nl.item(i) instanceof DocumentType) {
// We cannot import DocumentType's, so we need to manually copy it.
doctype = (DocumentType) nl.item(i);
}
}
Document doc;
if (doctype != null) {
doc = builder.getDOMImplementation().createDocument(
orig.getDocumentElement().getNamespaceURI(),
orig.getDocumentElement().getTagName(),
builder.getDOMImplementation().createDocumentType(
orig.getDoctype().getName(),
orig.getDoctype().getPublicId(),
orig.getDoctype().getSystemId()));
// XXX what about entity decls inside the DOCTYPE?
doc.removeChild(doc.getDocumentElement());
} else {
doc = builder.newDocument();
}
for (int i = 0; i < nl.getLength(); i++) {
Node node = nl.item(i);
if (!(node instanceof DocumentType)) {
try {
doc.appendChild(doc.importNode(node, true));
} catch (DOMException x) {
// Thrown in NB-Core-Build #2896 & 2898 inside GeneratedFilesHelper.applyBuildExtensions
throw new IOException("Could not import or append " + node + " of " + node.getClass(), x);
}
}
}
doc.normalize();
nl = doc.getElementsByTagName("*"); // NOI18N
for (int i = 0; i < nl.getLength(); i++) {
Element e = (Element) nl.item(i);
removeXmlBase(e);
NodeList nl2 = e.getChildNodes();
for (int j = 0; j < nl2.getLength(); j++) {
Node n = nl2.item(j);
if (n instanceof Text && ((Text) n).getNodeValue().trim().length() == 0) {
e.removeChild(n);
j--; // since list is dynamic
}
}
}
return doc;
}
/**
* Append a child element to the parent at the specified location.
*
* Starting with a valid document, append an element according to the schema
* sequence represented by the order. All existing child elements must be
* include as well as the new element. The existing child element following
* the new child is important, as the element will be 'inserted before', not
* 'inserted after'.
*
* @param parent parent to which the child will be appended
* @param el element to be added
* @param order order of the elements which must be followed
* @throws IllegalArgumentException if the order cannot be followed, either
* a missing existing or new child element is not specified in order
*
* @since 8.4
*/
public static void appendChildElement(Element parent, Element el, String[] order) throws IllegalArgumentException {
List l = Arrays.asList(order);
int index = l.indexOf(el.getLocalName());
// ensure the new new element is contained in the 'order'
if (index == -1) {
throw new IllegalArgumentException("new child element '"+ el.getLocalName() + "' not specified in order " + l); // NOI18N
}
List elements = findSubElements(parent);
Element insertBefore = null;
for (Element e : elements) {
int index2 = l.indexOf(e.getLocalName());
// ensure that all existing elements are in 'order'
if (index2 == -1) {
throw new IllegalArgumentException("Existing child element '" + e.getLocalName() + "' not specified in order " + l); // NOI18N
}
if (index2 > index) {
insertBefore = e;
break;
}
}
parent.insertBefore(el, insertBefore);
}
/**
* Find all direct child elements of an element.
* Children which are all-whitespace text nodes or comments are ignored; others cause
* an exception to be thrown.
* @param parent a parent element in a DOM tree
* @return a list of direct child elements (may be empty)
* @throws IllegalArgumentException if there are non-element children besides whitespace
*
* @since 8.4
*/
public static List findSubElements(Element parent) throws IllegalArgumentException {
NodeList l = parent.getChildNodes();
List elements = new ArrayList(l.getLength());
for (int i = 0; i < l.getLength(); i++) {
Node n = l.item(i);
if (n.getNodeType() == Node.ELEMENT_NODE) {
elements.add((Element) n);
} else if (n.getNodeType() == Node.TEXT_NODE) {
String text = ((Text) n).getNodeValue();
if (text.trim().length() > 0) {
throw new IllegalArgumentException("non-ws text encountered in " + parent + ": " + text); // NOI18N
}
} else if (n.getNodeType() == Node.COMMENT_NODE) {
// OK, ignore
} else {
throw new IllegalArgumentException("unexpected non-element child of " + parent + ": " + n); // NOI18N
}
}
return elements;
}
/**
* Search for an XML element in the direct children of parent only.
*
* This compares localName (nodeName if localName is null) to name,
* and checks the tags namespace with the provided namespace.
* A null namespace will match any namespace.
*
* This is differs from the DOM version by:
* - not searching recursively
* - returns a single result
*
*
* @param parent a parent element
* @param name the intended local name
* @param namespace the intended namespace (or null)
* @return the one child element with that name, or null if none
* @throws IllegalArgumentException if there is multiple elements of the same name
*
* @since 8.4
*/
public static Element findElement(Element parent, String name, String namespace) throws IllegalArgumentException {
Element result = null;
NodeList l = parent.getChildNodes();
int nodeCount = l.getLength();
for (int i = 0; i < nodeCount; i++) {
if (l.item(i).getNodeType() == Node.ELEMENT_NODE) {
Node node = l.item(i);
String localName = node.getLocalName();
localName = localName == null ? node.getNodeName() : localName;
if (name.equals(localName)
&& (namespace == null || namespace.equals(node.getNamespaceURI()))) {
if (result == null) {
result = (Element)node;
} else {
throw new IllegalArgumentException("more than one element with same name found");
}
}
}
}
return result;
}
/**
* Extract nested text from a node.
* Currently does not handle coalescing text nodes, CDATA sections, etc.
* @param parent a parent element
* @return the nested text, or null if none was found
*
* @since 8.4
*/
public static String findText(Node parent) {
NodeList l = parent.getChildNodes();
for (int i = 0; i < l.getLength(); i++) {
if (l.item(i).getNodeType() == Node.TEXT_NODE) {
Text text = (Text) l.item(i);
return text.getNodeValue();
}
}
return null;
}
/**
* Convert an XML fragment from one namespace to another.
*
* @param from element to translate
* @param namespace namespace to be translated to
* @return
*
* @since 8.4
*/
public static Element translateXML(Element from, String namespace) {
Element to = from.getOwnerDocument().createElementNS(namespace, from.getLocalName());
NodeList nl = from.getChildNodes();
int length = nl.getLength();
for (int i = 0; i < length; i++) {
Node node = nl.item(i);
Node newNode;
if (node.getNodeType() == Node.ELEMENT_NODE) {
newNode = translateXML((Element) node, namespace);
} else {
newNode = node.cloneNode(true);
}
to.appendChild(newNode);
}
NamedNodeMap m = from.getAttributes();
for (int i = 0; i < m.getLength(); i++) {
Node attr = m.item(i);
to.setAttribute(attr.getNodeName(), attr.getNodeValue());
}
return to;
}
/**
* Copy elements from one document to another attaching at the specified element
* and translating the namespace.
*
* @param from copy the children of this element (exclusive)
* @param to where to attach the copied elements
* @param newNamespace destination namespace
*
* @since 8.4
*/
public static void copyDocument(Element from, Element to, String newNamespace) {
Document doc = to.getOwnerDocument();
NodeList nl = from.getChildNodes();
int length = nl.getLength();
for (int i = 0; i < length; i++) {
Node node = nl.item(i);
Node newNode = null;
if (Node.ELEMENT_NODE == node.getNodeType()) {
Element oldElement = (Element) node;
newNode = doc.createElementNS(newNamespace, oldElement.getTagName());
NamedNodeMap m = oldElement.getAttributes();
Element newElement = (Element) newNode;
for (int index = 0; index < m.getLength(); index++) {
Node attr = m.item(index);
newElement.setAttribute(attr.getNodeName(), attr.getNodeValue());
}
copyDocument(oldElement, newElement, newNamespace);
} else {
newNode = node.cloneNode(true);
newNode = to.getOwnerDocument().importNode(newNode, true);
}
if (newNode != null) {
to.appendChild(newNode);
}
}
}
/**
* Create an XML error handler that rethrows errors and fatal errors and logs warnings.
* @return a standard error handler
*
* @since 8.4
*/
public static ErrorHandler defaultErrorHandler() {
return new ErrHandler();
}
private static final class ErrHandler implements ErrorHandler {
ErrHandler() {}
private void annotate(SAXParseException exception) throws SAXException {
Exceptions.attachMessage(exception, "Occurred at: " + exception.getSystemId() + ":" + exception.getLineNumber()); // NOI18N
}
public @Override void fatalError(SAXParseException exception) throws SAXException {
annotate(exception);
throw exception;
}
public @Override void error(SAXParseException exception) throws SAXException {
annotate(exception);
throw exception;
}
public @Override void warning(SAXParseException exception) throws SAXException {
annotate(exception);
Logger.getLogger(XMLUtil.class.getName()).log(Level.INFO, null, exception);
}
}
}