/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-09 Wolfgang M. Meier
* wolfgang@exist-db.org
* http://exist.sourceforge.net
*
* This program 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; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id$
*/
package org.exist.xquery.functions.request;
import java.util.Enumeration;
import org.apache.log4j.Logger;
import org.exist.dom.QName;
import org.exist.http.servlets.RequestWrapper;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Variable;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.JavaObjectValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;
import org.exist.xquery.value.ValueSequence;
/**
* @author Wolfgang Meier (wolfgang@exist-db.org)
*/
public class GetParameterNames extends BasicFunction {
protected static final Logger logger = Logger.getLogger(GetParameterNames.class);
public final static FunctionSignature signature =
new FunctionSignature(
new QName(
"get-parameter-names",
RequestModule.NAMESPACE_URI,
RequestModule.PREFIX),
"Returns a sequence containing the names of all parameters passed in the current request",
null,
new FunctionReturnSequenceType(Type.STRING, Cardinality.ZERO_OR_MORE, "the sequence containing the names of all parameters"));
/**
* @param context
*/
public GetParameterNames(XQueryContext context) {
super(context, signature);
}
/* (non-Javadoc)
* @see org.exist.xquery.BasicFunction#eval(org.exist.xquery.value.Sequence[], org.exist.xquery.value.Sequence)
*/
public Sequence eval(Sequence[] args, Sequence contextSequence)
throws XPathException {
final RequestModule myModule =
(RequestModule) context.getModule(RequestModule.NAMESPACE_URI);
// request object is read from global variable $request
final Variable var = myModule.resolveVariable(RequestModule.REQUEST_VAR);
if(var == null || var.getValue() == null)
{throw new XPathException(this, "No request object found in the current XQuery context.");}
if (var.getValue().getItemType() != Type.JAVA_OBJECT)
{throw new XPathException(this, "Variable $request is not bound to an Java object.");}
final JavaObjectValue value = (JavaObjectValue) var.getValue().itemAt(0);
if (value.getObject() instanceof RequestWrapper) {
final ValueSequence result = new ValueSequence();
for (final Enumeration<String> e =
((RequestWrapper) value.getObject()).getParameterNames();
e.hasMoreElements();
) {
final String param = e.nextElement();
result.add(new StringValue(param));
}
return result;
} else
{throw new XPathException(this, "Variable $request is not bound to a Request object.");}
}
}