/*
* eXist Open Source Native XML Database
* Copyright (C) 2005-2009 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 java.text.Collator;
import org.exist.dom.QName;
import org.exist.util.Collations;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Constants;
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.FunctionReturnSequenceType;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.IntegerValue;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
/**
*
* @author perig
* @author ljo
*
*/
public class FunCompare extends CollatingFunction {
public final static FunctionSignature signatures[] = {
new FunctionSignature (
new QName("compare", Function.BUILTIN_FUNCTION_NS),
"Returns the collatable comparison between $string-1 and $string-2, using $collation-uri. " +
"-1 if $string-1 is inferior to $string-2, 0 if $string-1 is equal " +
"to $string-2, 1 if $string-1 is superior to $string-2. " +
"If either comparand is the empty sequence, the empty sequence is " +
"returned. " +
"Please remember to specify the collation in the context or use, " +
"the three argument version if you don't want the system default.",
new SequenceType[] {
new FunctionParameterSequenceType("string-1", Type.STRING,
Cardinality.ZERO_OR_ONE, "The first string"),
new FunctionParameterSequenceType("string-2", Type.STRING,
Cardinality.ZERO_OR_ONE, "The second string")
},
new FunctionReturnSequenceType(Type.INTEGER, Cardinality.ZERO_OR_ONE,
"-1 if $string-1 is inferior to $string-2, " +
"0 if $string-1 is equal to $string-2, " +
"1 if $string-1 is superior to $string-2. " +
"If either comparand is the empty sequence, the empty sequence is returned.")),
new FunctionSignature (
new QName("compare", Function.BUILTIN_FUNCTION_NS),
"Returns the collatable comparison between $string-1 and $string-2, using $collation-uri. " +
"-1 if $string-1 is inferior to $string-2, 0 if $string-1 is equal " +
"to $string-2, 1 if $string-1 is superior to $string-2. " +
"If either comparand is the empty sequence, the empty sequence is returned. " +
THIRD_REL_COLLATION_ARG_EXAMPLE,
new SequenceType[] {
new FunctionParameterSequenceType("string-1", Type.STRING,
Cardinality.ZERO_OR_ONE, "The first string"),
new FunctionParameterSequenceType("string-2", Type.STRING,
Cardinality.ZERO_OR_ONE, "The second string"),
new FunctionParameterSequenceType("collation-uri", Type.STRING,
Cardinality.EXACTLY_ONE, "The relative collation URI")
},
new FunctionReturnSequenceType(Type.INTEGER, Cardinality.ZERO_OR_ONE,
"-1 if $string-1 is inferior to $string-2, " +
"0 if $string-1 is equal to $string-2, " +
"1 if $string-1 is superior to $string-2. " +
"If either comparand is the empty sequence, the empty sequence is returned."))
};
public FunCompare(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
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 seq1 = getArgument(0).eval(contextSequence, contextItem);
final Sequence seq2 = getArgument(1).eval(contextSequence, contextItem);
Sequence result;
if (seq1.isEmpty() || seq2.isEmpty()) {
result = Sequence.EMPTY_SEQUENCE;
} else {
final Collator collator = getCollator(contextSequence, contextItem, 3);
final int comparison = Collations.compare(collator, seq1.getStringValue(), seq2.getStringValue());
if (comparison == Constants.EQUAL)
{result = new IntegerValue(Constants.EQUAL);}
else if (comparison < 0)
{result = new IntegerValue(Constants.INFERIOR);}
else
{result = new IntegerValue(Constants.SUPERIOR);}
}
if (context.getProfiler().isEnabled())
{context.getProfiler().end(this, "", result);}
return result;
}
}