/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2009 The eXist Project
* http://exist-db.org
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $Id$
*/
package org.exist.xquery.functions.fn;
import org.exist.dom.QName;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Dependency;
import org.exist.xquery.Function;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Profiler;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.BooleanValue;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
/**
* xpath-library function: boolean(object)
*
*/
public class FunBoolean extends Function {
public final static FunctionSignature signature =
new FunctionSignature(
new QName("boolean", Function.BUILTIN_FUNCTION_NS),
"Computes the xs:boolean value of the sequence items.",
new SequenceType[] {
new FunctionParameterSequenceType("items", Type.ITEM,
Cardinality.ZERO_OR_MORE, "The items")
},
new FunctionReturnSequenceType(Type.BOOLEAN, Cardinality.ONE,
"The boolean value, ebv, of the items")
);
public FunBoolean(XQueryContext context) {
super(context, signature);
}
public int returnsType() {
return Type.BOOLEAN;
}
public Sequence eval(Sequence contextSequence, Item contextItem) throws XPathException {
if (context.getProfiler().isEnabled()) {
context.getProfiler().start(this);
context.getProfiler().message(this, Profiler.DEPENDENCIES,
"DEPENDENCIES", Dependency.getDependenciesName(this.getDependencies()));
if (contextSequence != null)
{context.getProfiler().message(this, Profiler.START_SEQUENCES,
"CONTEXT SEQUENCE", contextSequence);}
if (contextItem != null)
{context.getProfiler().message(this, Profiler.START_SEQUENCES,
"CONTEXT ITEM", contextItem.toSequence());}
}
final Sequence arg = getArgument(0).eval(contextSequence, contextItem);
final Sequence result = arg.effectiveBooleanValue() ?
BooleanValue.TRUE : BooleanValue.FALSE;
if (context.getProfiler().isEnabled())
{context.getProfiler().end(this, "", result);}
return result;
}
}