1. /* $Id: VariableExpander.java,v 1.6 2004/05/10 06:46:31 skitching Exp $

  2.  *

  3.  * Copyright 2003-2004 The Apache Software Foundation.

  4.  * 

  5.  * Licensed under the Apache License, Version 2.0 (the "License");

  6.  * you may not use this file except in compliance with the License.

  7.  * You may obtain a copy of the License at

  8.  * 

  9.  *      http://www.apache.org/licenses/LICENSE-2.0

  10.  * 

  11.  * Unless required by applicable law or agreed to in writing, software

  12.  * distributed under the License is distributed on an "AS IS" BASIS,

  13.  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  14.  * See the License for the specific language governing permissions and

  15.  * limitations under the License.

  16.  */ 

  17. 

  18. 

  19. package org.apache.commons.digester.substitution;

  20. 

  21. /**

  22.  * <p>An Interface describing a class capable of expanding strings which

  23.  * may contain variable references. The exact syntax of the "reference",

  24.  * and the mechanism for determining the corresponding value to be used

  25.  * is up to the concrete implementation.</p>

  26.  *

  27.  * @since 1.6

  28.  */

  29. public interface VariableExpander {

  30.     /**

  31.      * Return the input string with any variables replaced by their

  32.      * corresponding value. If there are no variables in the string,

  33.      * then the input parameter is returned unaltered.

  34.      */

  35.     public String expand(String param);

  36. }

  37.