mirror of git://gcc.gnu.org/git/gcc.git
550 lines
17 KiB
Java
550 lines
17 KiB
Java
/* Expr.java --
|
|
Copyright (C) 2004,2006 Free Software Foundation, Inc.
|
|
|
|
This file is part of GNU Classpath.
|
|
|
|
GNU Classpath 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, or (at your option)
|
|
any later version.
|
|
|
|
GNU Classpath 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
|
|
General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GNU Classpath; see the file COPYING. If not, write to the
|
|
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
02110-1301 USA.
|
|
|
|
Linking this library statically or dynamically with other modules is
|
|
making a combined work based on this library. Thus, the terms and
|
|
conditions of the GNU General Public License cover the whole
|
|
combination.
|
|
|
|
As a special exception, the copyright holders of this library give you
|
|
permission to link this library with independent modules to produce an
|
|
executable, regardless of the license terms of these independent
|
|
modules, and to copy and distribute the resulting executable under
|
|
terms of your choice, provided that you also meet, for each linked
|
|
independent module, the terms and conditions of the license of that
|
|
module. An independent module is a module which is not derived from
|
|
or based on this library. If you modify this library, you may extend
|
|
this exception to your version of the library, but you are not
|
|
obligated to do so. If you do not wish to do so, delete this
|
|
exception statement from your version. */
|
|
|
|
package gnu.xml.xpath;
|
|
|
|
import gnu.java.lang.CPStringBuilder;
|
|
|
|
import java.io.IOException;
|
|
import java.text.DecimalFormat;
|
|
import java.text.DecimalFormatSymbols;
|
|
import java.util.ArrayList;
|
|
import java.util.Collection;
|
|
import java.util.Collections;
|
|
import java.util.Comparator;
|
|
import java.util.HashSet;
|
|
import java.util.Iterator;
|
|
import java.util.List;
|
|
import java.util.Locale;
|
|
import java.util.Set;
|
|
import java.util.StringTokenizer;
|
|
import javax.xml.namespace.QName;
|
|
import javax.xml.parsers.DocumentBuilder;
|
|
import javax.xml.parsers.DocumentBuilderFactory;
|
|
import javax.xml.parsers.ParserConfigurationException;
|
|
import javax.xml.xpath.XPathConstants;
|
|
import javax.xml.xpath.XPathExpression;
|
|
import javax.xml.xpath.XPathExpressionException;
|
|
import org.w3c.dom.Document;
|
|
import org.w3c.dom.Node;
|
|
import org.w3c.dom.NodeList;
|
|
import org.xml.sax.InputSource;
|
|
import org.xml.sax.SAXException;
|
|
|
|
/**
|
|
* An XPath expression.
|
|
* This can be evaluated in the context of a node to produce a result.
|
|
*
|
|
* @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
|
|
*/
|
|
public abstract class Expr
|
|
implements XPathExpression
|
|
{
|
|
|
|
protected static final Comparator<Node> documentOrderComparator =
|
|
new DocumentOrderComparator();
|
|
|
|
protected static final DecimalFormat decimalFormat =
|
|
new DecimalFormat("####################################################" +
|
|
".####################################################",
|
|
new DecimalFormatSymbols(Locale.US));
|
|
|
|
static class ExprNodeSet implements NodeList
|
|
{
|
|
|
|
private ArrayList<Node> list;
|
|
|
|
ExprNodeSet(Collection<Node> collection)
|
|
{
|
|
if (collection instanceof ArrayList)
|
|
list = (ArrayList<Node>) collection;
|
|
else
|
|
list = new ArrayList<Node>(collection);
|
|
}
|
|
|
|
public int getLength()
|
|
{
|
|
return list.size();
|
|
}
|
|
|
|
public Node item(int index)
|
|
{
|
|
try
|
|
{
|
|
return list.get(index);
|
|
}
|
|
catch (ArrayIndexOutOfBoundsException e)
|
|
{
|
|
return null;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
public Object evaluate(Object item, QName returnType)
|
|
throws XPathExpressionException
|
|
{
|
|
Object ret = null;
|
|
Node context = null;
|
|
if (item instanceof Node)
|
|
{
|
|
context = (Node) item;
|
|
ret = evaluate(context, 1, 1);
|
|
if (XPathConstants.STRING == returnType &&
|
|
!(ret instanceof String))
|
|
{
|
|
ret = _string(context, ret);
|
|
}
|
|
else if (XPathConstants.NUMBER == returnType &&
|
|
!(ret instanceof Double))
|
|
{
|
|
ret = new Double(_number(context, ret));
|
|
}
|
|
else if (XPathConstants.BOOLEAN == returnType &&
|
|
!(ret instanceof Boolean))
|
|
{
|
|
ret = _boolean(context, ret) ? Boolean.TRUE : Boolean.FALSE;
|
|
}
|
|
else if (XPathConstants.NODE == returnType)
|
|
{
|
|
if (ret instanceof Collection)
|
|
{
|
|
/* Suppression is safe, as we know context
|
|
produces Collection<Node> */
|
|
@SuppressWarnings("unchecked")
|
|
Collection<Node> ns = (Collection<Node>) ret;
|
|
switch (ns.size())
|
|
{
|
|
case 0:
|
|
ret = null;
|
|
break;
|
|
case 1:
|
|
ret = ns.iterator().next();
|
|
break;
|
|
default:
|
|
throw new XPathExpressionException("multiple nodes in node-set");
|
|
}
|
|
}
|
|
else if (ret != null)
|
|
{
|
|
throw new XPathExpressionException("return value is not a node-set");
|
|
}
|
|
}
|
|
else if (XPathConstants.NODESET == returnType)
|
|
{
|
|
if (ret != null && !(ret instanceof Collection))
|
|
{
|
|
throw new XPathExpressionException("return value is not a node-set");
|
|
}
|
|
if (ret != null)
|
|
{
|
|
/* Suppression is safe, as we know context produces Collection<Node> */
|
|
@SuppressWarnings("unchecked")
|
|
Collection<Node> nodes = (Collection<Node>) ret;
|
|
ret = new ExprNodeSet(nodes);
|
|
}
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
public String evaluate(Object item)
|
|
throws XPathExpressionException
|
|
{
|
|
return (String) evaluate(item, XPathConstants.STRING);
|
|
}
|
|
|
|
public Object evaluate(InputSource source, QName returnType)
|
|
throws XPathExpressionException
|
|
{
|
|
try
|
|
{
|
|
DocumentBuilderFactory factory =
|
|
new gnu.xml.dom.JAXPFactory();
|
|
DocumentBuilder builder = factory.newDocumentBuilder();
|
|
Document doc = builder.parse(source);
|
|
return evaluate(doc, returnType);
|
|
}
|
|
catch (ParserConfigurationException e)
|
|
{
|
|
throw new XPathExpressionException(e);
|
|
}
|
|
catch (SAXException e)
|
|
{
|
|
throw new XPathExpressionException(e);
|
|
}
|
|
catch (IOException e)
|
|
{
|
|
throw new XPathExpressionException(e);
|
|
}
|
|
}
|
|
|
|
public String evaluate(InputSource source)
|
|
throws XPathExpressionException
|
|
{
|
|
return (String) evaluate(source, XPathConstants.STRING);
|
|
}
|
|
|
|
public abstract Object evaluate(Node context, int pos, int len);
|
|
|
|
public abstract Expr clone(Object context);
|
|
|
|
public abstract boolean references(QName var);
|
|
|
|
/* -- 4.1 Node Set Functions -- */
|
|
|
|
/**
|
|
* The id function selects elements by their unique ID.
|
|
* When the argument to id is of type node-set, then the result is
|
|
* the union of the result of applying id to the string-value of each of
|
|
* the nodes in the argument node-set. When the argument to id is of any
|
|
* other type, the argument is converted to a string as if by a call to
|
|
* the string function; the string is split into a whitespace-separated
|
|
* list of tokens (whitespace is any sequence of characters matching the
|
|
* production S); the result is a node-set containing the elements in the
|
|
* same document as the context node that have a unique ID equal to any of
|
|
* the tokens in the list.
|
|
*/
|
|
public static Collection<Node> _id(Node context, Object object)
|
|
{
|
|
Set<Node> ret = new HashSet<Node>();
|
|
if (object instanceof Collection)
|
|
{
|
|
/* Suppression is safe, as the iteration will check each value is a Node */
|
|
@SuppressWarnings("unchecked")
|
|
Collection<Node> nodeSet = (Collection<Node>) object;
|
|
for (Iterator<Node> i = nodeSet.iterator(); i.hasNext(); )
|
|
{
|
|
String string = stringValue(i.next());
|
|
ret.addAll(_id (context, string));
|
|
}
|
|
}
|
|
else
|
|
{
|
|
Document doc = (context instanceof Document) ? (Document) context :
|
|
context.getOwnerDocument();
|
|
String string = _string(context, object);
|
|
StringTokenizer st = new StringTokenizer(string, " \t\r\n");
|
|
while (st.hasMoreTokens())
|
|
{
|
|
Node element = doc.getElementById(st.nextToken());
|
|
if (element != null)
|
|
{
|
|
ret.add(element);
|
|
}
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* The local-name function returns the local part of the expanded-name of
|
|
* the node in the argument node-set that is first in document order. If
|
|
* the argument node-set is empty or the first node has no expanded-name,
|
|
* an empty string is returned. If the argument is omitted, it defaults to
|
|
* a node-set with the context node as its only member.
|
|
*/
|
|
public static String _local_name(Node context, Collection<Node> nodeSet)
|
|
{
|
|
if (nodeSet == null || nodeSet.isEmpty())
|
|
return "";
|
|
Node node = firstNode(nodeSet);
|
|
String ret = node.getLocalName();
|
|
return (ret == null) ? "" : ret;
|
|
}
|
|
|
|
/**
|
|
* The namespace-uri function returns the namespace URI of the
|
|
* expanded-name of the node in the argument node-set that is first in
|
|
* document order. If the argument node-set is empty, the first node has
|
|
* no expanded-name, or the namespace URI of the expanded-name is null, an
|
|
* empty string is returned. If the argument is omitted, it defaults to a
|
|
* node-set with the context node as its only member.
|
|
*/
|
|
public static String _namespace_uri(Node context, Collection<Node> nodeSet)
|
|
{
|
|
if (nodeSet == null || nodeSet.isEmpty())
|
|
return "";
|
|
Node node = firstNode(nodeSet);
|
|
String ret = node.getNamespaceURI();
|
|
return (ret == null) ? "" : ret;
|
|
}
|
|
|
|
/**
|
|
* The name function returns a string containing a QName representing the
|
|
* expanded-name of the node in the argument node-set that is first in
|
|
* document order. The QName must represent the expanded-name with respect
|
|
* to the namespace declarations in effect on the node whose expanded-name
|
|
* is being represented. Typically, this will be the QName that occurred
|
|
* in the XML source. This need not be the case if there are namespace
|
|
* declarations in effect on the node that associate multiple prefixes
|
|
* with the same namespace. However, an implementation may include
|
|
* information about the original prefix in its representation of nodes;
|
|
* in this case, an implementation can ensure that the returned string is
|
|
* always the same as the QName used in the XML source. If the argument
|
|
* node-set is empty or the first node has no expanded-name, an empty
|
|
* string is returned. If the argument it omitted, it defaults to a
|
|
* node-set with the context node as its only member.
|
|
*/
|
|
public static String _name(Node context, Collection<Node> nodeSet)
|
|
{
|
|
if (nodeSet == null || nodeSet.isEmpty())
|
|
return "";
|
|
Node node = firstNode(nodeSet);
|
|
String ret = null;
|
|
switch (node.getNodeType())
|
|
{
|
|
case Node.ATTRIBUTE_NODE:
|
|
case Node.ELEMENT_NODE:
|
|
case Node.PROCESSING_INSTRUCTION_NODE:
|
|
ret = node.getNodeName();
|
|
}
|
|
return (ret == null) ? "" : ret;
|
|
}
|
|
|
|
/**
|
|
* Returns the first node in the set in document order.
|
|
*/
|
|
static Node firstNode(Collection<Node> nodeSet)
|
|
{
|
|
List<Node> list = new ArrayList<Node>(nodeSet);
|
|
Collections.sort(list, documentOrderComparator);
|
|
return list.get(0);
|
|
}
|
|
|
|
/* -- 4.2 String Functions -- */
|
|
|
|
/**
|
|
* Implementation of the XPath <code>string</code> function.
|
|
*/
|
|
public static String _string(Node context, Object object)
|
|
{
|
|
if (object == null)
|
|
{
|
|
return stringValue(context);
|
|
}
|
|
if (object instanceof String)
|
|
{
|
|
return (String) object;
|
|
}
|
|
if (object instanceof Boolean)
|
|
{
|
|
return object.toString();
|
|
}
|
|
if (object instanceof Double)
|
|
{
|
|
double d = ((Double) object).doubleValue();
|
|
if (Double.isNaN(d))
|
|
{
|
|
return "NaN";
|
|
}
|
|
else if (d == 0.0d)
|
|
{
|
|
return "0";
|
|
}
|
|
else if (Double.isInfinite(d))
|
|
{
|
|
if (d < 0)
|
|
{
|
|
return "-Infinity";
|
|
}
|
|
else
|
|
{
|
|
return "Infinity";
|
|
}
|
|
}
|
|
else
|
|
{
|
|
String ret = decimalFormat.format(d);
|
|
if (ret.endsWith (".0"))
|
|
{
|
|
ret = ret.substring(0, ret.length() - 2);
|
|
}
|
|
return ret;
|
|
}
|
|
}
|
|
if (object instanceof Collection)
|
|
{
|
|
/* Suppression is safe, as we fail immediately if the
|
|
* first element is not a Node and don't use the rest */
|
|
@SuppressWarnings("unchecked")
|
|
Collection<Node> nodeSet = (Collection<Node>) object;
|
|
if (nodeSet.isEmpty())
|
|
{
|
|
return "";
|
|
}
|
|
Node node = firstNode(nodeSet);
|
|
return stringValue(node);
|
|
}
|
|
throw new IllegalArgumentException(object.toString());
|
|
}
|
|
|
|
/* -- 4.3 Boolean Functions -- */
|
|
|
|
/**
|
|
* Implementation of the XPath <code>boolean</code> function.
|
|
*/
|
|
public static boolean _boolean(Node context, Object object)
|
|
{
|
|
if (object instanceof Boolean)
|
|
{
|
|
return ((Boolean) object).booleanValue();
|
|
}
|
|
if (object instanceof Double)
|
|
{
|
|
Double value = (Double) object;
|
|
if (value.isNaN())
|
|
return false;
|
|
return value.doubleValue() != 0.0;
|
|
}
|
|
if (object instanceof String)
|
|
{
|
|
return ((String) object).length() != 0;
|
|
}
|
|
if (object instanceof Collection)
|
|
{
|
|
return ((Collection<?>) object).size() != 0;
|
|
}
|
|
return false; // TODO user defined types
|
|
}
|
|
|
|
/* -- 4.4 Number Functions -- */
|
|
|
|
/**
|
|
* Implementation of the XPath <code>number</code> function.
|
|
*/
|
|
public static double _number(Node context, Object object)
|
|
{
|
|
if (object == null)
|
|
{
|
|
object = Collections.singleton(context);
|
|
}
|
|
if (object instanceof Double)
|
|
{
|
|
return ((Double) object).doubleValue();
|
|
}
|
|
if (object instanceof Boolean)
|
|
{
|
|
return ((Boolean) object).booleanValue() ? 1.0 : 0.0;
|
|
}
|
|
if (object instanceof Collection)
|
|
{
|
|
/* Suppression is safe, as we fail immediately if one
|
|
* of the elements is not a Node */
|
|
@SuppressWarnings("unchecked")
|
|
Collection<Node> nodeSet = (Collection<Node>) object;
|
|
// Convert node-set to string
|
|
object = stringValue(nodeSet);
|
|
}
|
|
if (object instanceof String)
|
|
{
|
|
String string = ((String) object).trim();
|
|
try
|
|
{
|
|
return Double.parseDouble(string);
|
|
}
|
|
catch (NumberFormatException e)
|
|
{
|
|
return Double.NaN;
|
|
}
|
|
}
|
|
return Double.NaN; // TODO user-defined types
|
|
}
|
|
|
|
/**
|
|
* Computes the XPath string-value of the specified node-set.
|
|
*/
|
|
public static String stringValue(Collection<Node> nodeSet)
|
|
{
|
|
CPStringBuilder buf = new CPStringBuilder();
|
|
for (Iterator<Node> i = nodeSet.iterator(); i.hasNext(); )
|
|
{
|
|
buf.append(stringValue(i.next()));
|
|
}
|
|
return buf.toString();
|
|
}
|
|
|
|
/**
|
|
* Computes the XPath string-value of the specified node.
|
|
*/
|
|
public static String stringValue(Node node)
|
|
{
|
|
return stringValue(node, false);
|
|
}
|
|
|
|
static String stringValue(Node node, boolean elementMode)
|
|
{
|
|
switch (node.getNodeType())
|
|
{
|
|
case Node.DOCUMENT_NODE: // 5.1 Root Node
|
|
case Node.DOCUMENT_FRAGMENT_NODE:
|
|
case Node.ELEMENT_NODE: // 5.2 Element Nodes
|
|
CPStringBuilder buf = new CPStringBuilder();
|
|
for (Node ctx = node.getFirstChild(); ctx != null;
|
|
ctx = ctx.getNextSibling())
|
|
{
|
|
buf.append(stringValue(ctx, true));
|
|
}
|
|
return buf.toString();
|
|
case Node.TEXT_NODE: // 5.7 Text Nodes
|
|
case Node.CDATA_SECTION_NODE:
|
|
return node.getNodeValue();
|
|
case Node.ATTRIBUTE_NODE: // 5.3 Attribute Nodes
|
|
case Node.PROCESSING_INSTRUCTION_NODE: // 5.5 Processing Instruction
|
|
case Node.COMMENT_NODE: // 5.6 Comment Nodes
|
|
if (!elementMode)
|
|
{
|
|
return node.getNodeValue();
|
|
}
|
|
default:
|
|
return "";
|
|
}
|
|
}
|
|
|
|
static int intValue(Object val)
|
|
{
|
|
if (val instanceof Double)
|
|
{
|
|
Double d = (Double) val;
|
|
return d.isNaN() ? 0 : d.intValue();
|
|
}
|
|
else
|
|
return (int) Math.ceil(_number(null, val));
|
|
}
|
|
|
|
}
|