com.caucho.xml.XmlUtil Maven / Gradle / Ivy
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/*
* Copyright (c) 1998-2012 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source 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, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.xml;
import com.caucho.util.CharBuffer;
import org.w3c.dom.Comment;
import org.w3c.dom.Document;
import org.w3c.dom.DocumentFragment;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.ProcessingInstruction;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import java.io.IOException;
import java.util.HashMap;
/**
* XML utilities for manipulating names and the DOM.
*/
public class XmlUtil {
/**
* Treats the string as an attribute list, splitting it into a HashMap.
*
* @param name a string to be interpreted as an attribute list
* @return a hash map containing the attribute (key, value) pairs.
*/
public static HashMap splitNameList(String name)
throws IOException
{
HashMap attrs = new HashMap();
CharBuffer cb = new CharBuffer();
int length = name.length();
int i = 0;
int ch = 0;
while (i < length) {
for (; i < length && XmlChar.isWhitespace(ch = name.charAt(i)); i++) {
}
if (i < length && ! XmlChar.isNameStart(ch))
throw new IOException("expected name at " + (char) ch);
cb.clear();
while (i < length && XmlChar.isNameChar(ch)) {
cb.append((char) ch);
ch = name.charAt(++i);
}
String key = cb.toString();
cb.clear();
for (; i < length && XmlChar.isWhitespace(ch = name.charAt(i)); i++) {
}
if (ch != '=') {
attrs.put(key, "");
continue;
}
while (++i < length && XmlChar.isWhitespace(ch = name.charAt(i))) {
}
if (i >= length)
break;
cb.clear();
if (ch == '\'') {
while (++i < length && (ch = name.charAt(i)) != '\'')
cb.append((char) ch);
i++;
} else if (ch == '"') {
while (++i < length && (ch = name.charAt(i)) != '\"')
cb.append((char) ch);
i++;
} else if (XmlChar.isNameChar(ch)) {
cb.append((char) ch);
while (++i < length && XmlChar.isNameChar(ch = name.charAt(i)))
cb.append((char) ch);
} else
throw new IOException("unexpected");
attrs.put(key, cb.toString());
}
return attrs;
}
/**
* Extracts an attribute from a processing instruction. Since
* processing instructions are opaque, the standard DOM has no API
* for the common case where the PI value is an attribute list.
*
*
* <?xml-stylesheet href="default.xsl"?>
*
In the above example,
* getPIAttribute(node.getNodeValue(), "href")
* - If the node has a child, return the child
*
- Else if the node has a following sibling, return that sibling
*
- Else if the node has a following uncle, return that uncle
*
*
* @param node the current node
* @return the next node in the preorder traversal
*/
public static Node getNext(Node node)
{
if (node == null)
return null;
if (node.getFirstChild() != null)
return node.getFirstChild();
for (; node != null; node = node.getParentNode()) {
if (node.getNextSibling() != null)
return node.getNextSibling();
}
return null;
}
/**
* Get the previous node in a DFS preorder traversal
*
* @param node the current node
* @return the previous node in the preorder traversal
*/
public static Node getPrevious(Node node)
{
Node previous;
if (node == null)
return null;
if ((previous = node.getPreviousSibling()) != null) {
for (;
previous.getLastChild() != null;
previous = previous.getLastChild()) {
}
return previous;
}
return node.getParentNode();
}
/**
* Extracts the text value from the node. Text nodes return their
* value and elements return the concatenation of the child values.
*/
public static String textValue(Node node)
{
if (node instanceof Element || node instanceof DocumentFragment) {
String s = null;
CharBuffer cb = null;
for (Node child = node.getFirstChild();
child != null;
child = child.getNextSibling()) {
String value = null;
if (child instanceof Element || child instanceof Document) {
if (cb == null)
cb = new CharBuffer();
if (s != null)
cb.append(s);
s = null;
textValue(cb, child);
}
else if ((value = child.getNodeValue()) == null || value == "") {
}
else if (cb != null)
cb.append(value);
else if (s == null && s != "") {
s = value;
}
else {
cb = new CharBuffer();
cb.append(s);
cb.append(value);
s = null;
}
}
if (s != null)
return s;
else if (cb != null)
return cb.toString();
else
return "";
}
else {
String value = node.getNodeValue();
if (value != null)
return value;
else
return "";
}
}
/**
* Extracts the text value from the node. Text nodes return their
* value and elements return the concatenation of the child values.
*/
public static void textValue(CharBuffer cb, Node node)
{
if (node instanceof Element || node instanceof DocumentFragment) {
for (Node child = node.getFirstChild();
child != null;
child = child.getNextSibling()) {
textValue(cb, child);
}
}
else if (node instanceof Comment || node instanceof ProcessingInstruction) {
}
else
cb.append(node.getNodeValue());
}
/**
* Extracts the text value from the node. Text nodes return their
* value and elements return the concatenation of the child values.
*/
public static boolean isWhitespace(String text)
{
for (int i = text.length() - 1; i >= 0; i--) {
if (! XmlChar.isWhitespace(text.charAt(i)))
return false;
}
return true;
}
/**
* Sends data to the helper.
*/
public static void toSAX(Node node, ContentHandler handler)
throws SAXException
{
for (; node != null; node = node.getNextSibling()) {
if (node instanceof ProcessingInstruction) {
ProcessingInstruction pi = (ProcessingInstruction) node;
handler.processingInstruction(pi.getNodeName(), pi.getData());
}
else if (node instanceof DocumentFragment) {
toSAX(node.getFirstChild(), handler);
}
}
}
/**
* Returns the namespace for the given prefix.
*/
public static String getNamespace(Node node, String prefix)
{
for (; node != null; node = node.getParentNode()) {
if (node instanceof CauchoElement)
return ((CauchoElement) node).getNamespace(prefix);
}
return null;
}
}