code: /*
   * 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.
   */
  /*
   * $Id$
   */
  package org.apache.xpath.functions;
  
  import org.apache.xpath.XPathContext;
  import org.apache.xpath.objects.XObject;
  import org.apache.xpath.objects.XString;
  
  /**
   * Execute the Translate() function.
   * @xsl.usage advanced
   */
  public class FuncTranslate extends Function3Args
  {
      static final long serialVersionUID = -1672834340026116482L;
  
    /**
     * Execute the function.  The function must return
     * a valid object.
     * @param xctxt The current execution context.
     * @return A valid XObject.
     *
     * @throws javax.xml.transform.TransformerException
     */
    public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
    {
  
      String theFirstString = m_arg0.execute(xctxt).str();
      String theSecondString = m_arg1.execute(xctxt).str();
      String theThirdString = m_arg2.execute(xctxt).str();
      int theFirstStringLength = theFirstString.length();
      int theThirdStringLength = theThirdString.length();
  
      // A vector to contain the new characters.  We'll use it to construct
      // the result string.
      StringBuffer sbuffer = new StringBuffer();
  
      for (int i = 0; i < theFirstStringLength; i++)
      {
        char theCurrentChar = theFirstString.charAt(i);
        int theIndex = theSecondString.indexOf(theCurrentChar);
  
        if (theIndex < 0)
        {
  
          // Didn't find the character in the second string, so it
          // is not translated.
          sbuffer.append(theCurrentChar);
        }
        else if (theIndex < theThirdStringLength)
        {
  
          // OK, there's a corresponding character in the
          // third string, so do the translation...
          sbuffer.append(theThirdString.charAt(theIndex));
        }
        else
        {
  
          // There's no corresponding character in the
          // third string, since it's shorter than the
          // second string.  In this case, the character
          // is removed from the output string, so don't
          // do anything.
        }
      }
  
      return new XString(sbuffer.toString());
    }
  }
  