001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.logging.log4j.core.config.plugins.visitors;
019
020import org.apache.logging.log4j.core.LogEvent;
021import org.apache.logging.log4j.core.config.Configuration;
022import org.apache.logging.log4j.core.config.Node;
023import org.apache.logging.log4j.core.config.plugins.PluginNode;
024
025/**
026 * PluginVisitor implementation for {@link PluginNode}
027 */
028public class PluginNodeVisitor extends AbstractPluginVisitor<PluginNode> {
029    public PluginNodeVisitor() {
030        super(PluginNode.class);
031    }
032
033    @Override
034    public Object visit(final Configuration configuration, final Node node, final LogEvent event,
035                        final StringBuilder log) {
036        if (this.conversionType.isInstance(node)) {
037            log.append("Node=").append(node.getName());
038            return node;
039        }
040        LOGGER.warn("Variable annotated with @PluginNode is not compatible with the type {}.", node.getClass());
041        return null;
042    }
043}