core/src/main/java/org/apache/commons/digester3/SetNextRule.java

package org.apache.commons.digester3;

/*
 * 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.
 */


/**
 * <p>
 * Rule implementation that calls a method on the (top-1) (parent) object, passing the top object (child) as an
 * argument. It is commonly used to establish parent-child relationships.
 * </p>
 * <p>
 * This rule now supports more flexible method matching by default. It is possible that this may break (some) code
 * written against release 1.1.1 or earlier. See {@link #isExactMatch()} for more details.
 * </p>
 * <p>
 * Note that while CallMethodRule uses commons-beanutils' data-conversion functionality (ConvertUtils class) to convert
 * parameter values into the appropriate type for the parameter to the called method, this rule does not. Needing to use
 * ConvertUtils functionality when building parent-child relationships is expected to be very rare; however if you do
 * need this then instead of using this rule, create a CallMethodRule specifying targetOffset of 1 in the constructor.
 * </p>
 */
public class SetNextRule
    extends AbstractMethodRule
{

    // ----------------------------------------------------------- Constructors

    /**
     * Construct a "set next" rule with the specified method name. The method's argument type is assumed to be the class
     * of the child object.
     * 
     * @param methodName Method name of the parent method to call
     */
    public SetNextRule( final String methodName )
    {
        super( methodName );
    }

    /**
     * Construct a "set next" rule with the specified method name.
     * 
     * @param methodName Method name of the parent method to call
     * @param paramType Java class name of the parent method's argument (if you wish to use a primitive type,
     *                  specify the corresonding Java wrapper class instead, such as <code>java.lang.Boolean</code>
     *                  for a <code>boolean</code> parameter)
     */
    public SetNextRule( final String methodName, final String paramType )
    {
        super( methodName, paramType );
    }

    /**
     * Construct a "set next" rule with the specified method name.
     * 
     * @param methodName Method name of the parent method to call
     * @param paramType Java class of the parent method's argument (if you wish to use a primitive type, specify the
     *                  corresonding Java wrapper class instead, such as <code>java.lang.Boolean</code> for a
     *                  <code>boolean</code> parameter)
     */
    public SetNextRule( final String methodName, final Class<?> paramType )
    {
        super( methodName, paramType );
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected Object getChild()
    {
        return getDigester().peek( 0 );
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected Object getParent()
    {
        return getDigester().peek( 1 );
    }

}