Commons Digester example source code file (Substitutor.java)

This example Commons Digester source code file (Substitutor.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons Digester tags/keywords

attributes, attributes, sax, string, string, substitutor, substitutor

The Commons Digester Substitutor.java source code

/* $Id: Substitutor.java 992060 2010-09-02 19:09:47Z simonetripodi $
 *
 * 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 org.apache.commons.digester;

import org.xml.sax.Attributes;

/**
 * <p>(Logical) Interface for substitution strategies.
 * (It happens to be implemented as a Java abstract class to allow
 * future additions to be made without breaking backwards compatibility.)
 * </p>
 * <p>
 * Usage: When {@link Digester#setSubstitutor} is set, <code>Digester
 * calls the methods in this interface to create substitute values which will
 * be passed into the Rule implementations.
 * Of course, it is perfectly acceptable for implementations not to make 
 * substitutions and simply return the inputs.
 * </p>
 * <p>Different strategies are supported for attributes and body text.

 *
 * @since 1.6 
 */
public abstract class Substitutor {
    
    /**
     * <p>Substitutes the attributes (before they are passed to the 
     * <code>Rule implementations's).

     *
     * <p>Digester will only call this method a second time 
     * once the original <code>Attributes instance can be safely reused. 
     * The implementation is therefore free to reuse the same <code>Attributes instance
     * for all calls.</p>
     *
     * @param attributes the <code>Attributes passed into Digester by the SAX parser, 
     * not null (but may be empty)
     * @return <code>Attributes to be passed to the Rule implementations. 
     * This method may pass back the Attributes passed in.
     * Not null but possibly empty.
     */
    public abstract Attributes substitute(Attributes attributes);
    
    /**
     * Substitutes for the body text.
     * This method may substitute values into the body text of the
     * elements that Digester parses.
     *
     * @param bodyText the body text (as passed to <code>Digester)
     * @return the body text to be passed to the <code>Rule implementations
     */
    public abstract String substitute(String bodyText);
}