/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * 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.

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package com.sun.org.apache.xpath.internal.functions;

import com.sun.org.apache.xpath.internal.XPathContext;

import com.sun.org.apache.xpath.internal.objects.XObject;

import com.sun.org.apache.xpath.internal.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());

  }

}