001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements. See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership. The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the  "License");
007     * you may not use this file except in compliance with the License.
008     * You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    /*
019     * $Id: FuncSubstringBefore.java 468655 2006-10-28 07:12:06Z minchau $
020     */
021    package org.apache.xpath.functions;
022    
023    import org.apache.xpath.XPathContext;
024    import org.apache.xpath.objects.XObject;
025    import org.apache.xpath.objects.XString;
026    
027    /**
028     * Execute the SubstringBefore() function.
029     * @xsl.usage advanced
030     */
031    public class FuncSubstringBefore extends Function2Args
032    {
033        static final long serialVersionUID = 4110547161672431775L;
034    
035      /**
036       * Execute the function.  The function must return
037       * a valid object.
038       * @param xctxt The current execution context.
039       * @return A valid XObject.
040       *
041       * @throws javax.xml.transform.TransformerException
042       */
043      public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
044      {
045    
046        String s1 = m_arg0.execute(xctxt).str();
047        String s2 = m_arg1.execute(xctxt).str();
048        int index = s1.indexOf(s2);
049    
050        return (-1 == index)
051               ? XString.EMPTYSTRING : new XString(s1.substring(0, index));
052      }
053    }