/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.hp.hpl.jena.sparql.function.library;
//import org.apache.commons.logging.*;
import java.util.ArrayList ;
import java.util.Iterator ;
import java.util.List ;
import org.apache.jena.atlas.lib.StrUtils ;
import com.hp.hpl.jena.query.QueryBuildException ;
import com.hp.hpl.jena.sparql.ARQInternalErrorException ;
import com.hp.hpl.jena.sparql.expr.ExprList ;
import com.hp.hpl.jena.sparql.expr.NodeValue ;
import com.hp.hpl.jena.sparql.function.FunctionBase ;
import com.hp.hpl.jena.sparql.util.Utils ;
/** Function that concatenates strings using a separator.
* This is not fn:string-join because
* (1) that takes a sequence as argument
* (2) the arguments are in a different order
*/
public class strjoin extends FunctionBase
{
@Override
public final NodeValue exec(List<NodeValue> args)
{
if ( args == null )
// The contract on the function interface is that this should not happen.
throw new ARQInternalErrorException(Utils.className(this)+": Null args list") ;
Iterator<NodeValue> iter = args.iterator() ;
String sep = iter.next().asString() ;
List<String> x = new ArrayList<String>() ;
for ( ; iter.hasNext() ; )
{
NodeValue arg = iter.next();
x.add( arg.asString() ) ;
}
return NodeValue.makeString(StrUtils.strjoin(sep, x)) ;
}
@Override
public void checkBuild(String uri, ExprList args)
{
if ( args.size() < 1 )
throw new QueryBuildException("Function '"+Utils.className(this)+"' requires at least one arguments") ;
}
}