DocumentFunction.java [plain text]
package gnu.xml.transform;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.TreeSet;
import javax.xml.transform.TransformerException;
import javax.xml.transform.dom.DOMSource;
import javax.xml.xpath.XPathFunction;
import javax.xml.xpath.XPathFunctionException;
import org.w3c.dom.Node;
import gnu.xml.xpath.Constant;
import gnu.xml.xpath.Expr;
import gnu.xml.xpath.Function;
import gnu.xml.xpath.IdFunction;
final class DocumentFunction
extends Expr
implements Function, XPathFunction
{
final Stylesheet stylesheet;
final Node base;
List args;
List values;
DocumentFunction(Stylesheet stylesheet, Node base)
{
this.stylesheet = stylesheet;
this.base = base;
}
public Object evaluate(List args)
throws XPathFunctionException
{
values = args;
return evaluate(null, 1, 1);
}
public void setArguments(List args)
{
this.args = args;
}
public Object evaluate(Node context, int pos, int len)
{
int arity = args.size();
if (values == null)
{
values = new ArrayList(arity);
for (int i = 0; i < arity; i++)
{
Expr arg = (Expr) args.get(i);
values.add(arg.evaluate(context, pos, len));
}
}
Object ret;
switch (arity)
{
case 1:
Object arg = values.get(0);
if (arg instanceof Collection)
{
Collection ns = (Collection) arg;
Collection acc = new TreeSet();
for (Iterator i = ns.iterator(); i.hasNext(); )
{
Node node = (Node) i.next();
String s = Expr.stringValue(node);
acc.addAll(document(s, node.getBaseURI()));
}
ret = acc;
}
else
{
String s = Expr._string(context, arg);
ret = document(s, base.getBaseURI());
}
break;
case 2:
Object arg1 = values.get(0);
Object arg2 = values.get(1);
if (!(arg2 instanceof Collection))
{
throw new RuntimeException("second argument is not a node-set");
}
Collection arg2ns = (Collection) arg2;
String base2 = arg2ns.isEmpty() ? null :
((Node) arg2ns.iterator().next()).getBaseURI();
if (arg1 instanceof Collection)
{
Collection arg1ns = (Collection) arg1;
Collection acc = new TreeSet();
for (Iterator i = arg1ns.iterator(); i.hasNext(); )
{
Node node = (Node) i.next();
String s = Expr.stringValue(node);
acc.addAll(document(s, base2));
}
ret = acc;
}
else
{
String s = Expr._string(context, arg1);
ret = document(s, base2);
}
break;
default:
throw new RuntimeException("invalid arity");
}
values = null;
return ret;
}
Collection document(String uri, String base)
{
if ("".equals(uri) || uri == null)
{
uri = this.base.getBaseURI();
}
Expr fragment = null;
int hi = uri.indexOf('#');
if (hi != -1)
{
String f = uri.substring(hi + 1);
uri = uri.substring(0, hi);
fragment = new IdFunction(new Constant(f));
}
try
{
DOMSource source;
XSLURIResolver resolver = stylesheet.factory.resolver;
synchronized (resolver)
{
if (stylesheet.transformer != null)
{
resolver.setUserResolver(stylesheet.transformer.uriResolver);
resolver.setUserListener(stylesheet.transformer.errorListener);
}
source = resolver.resolveDOM(null, base, uri);
}
Node node = source.getNode();
if (fragment == null)
{
return Collections.singleton(node);
}
else
{
Object ret = fragment.evaluate(node, 1, 1);
if (!(ret instanceof Collection))
{
return Collections.EMPTY_SET;
}
return (Collection) ret;
}
}
catch (TransformerException e)
{
String msg = "can't open " + uri;
if (base != null)
{
msg += " with base " + base;
}
throw new RuntimeException(msg);
}
}
public Expr clone(Object context)
{
Stylesheet s = stylesheet;
if (context instanceof Stylesheet)
{
s = (Stylesheet) context;
}
DocumentFunction f = new DocumentFunction(s, base);
int len = args.size();
List args2 = new ArrayList(len);
for (int i = 0; i < len; i++)
{
args2.add(((Expr) args.get(i)).clone(context));
}
f.setArguments(args2);
return f;
}
}