gateway-test-utils/src/main/java/org/apache/knox/test/log/CollectAppender.java

/*
 * 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.knox.test.log;

import org.apache.logging.log4j.core.Appender;
import org.apache.logging.log4j.core.Core;
import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.appender.AbstractAppender;
import org.apache.logging.log4j.core.config.Property;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;

import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;

@Plugin(
    name = "CollectAppender",
    category = Core.CATEGORY_NAME,
    elementType = Appender.ELEMENT_TYPE)
public class CollectAppender extends AbstractAppender {
  public static final BlockingQueue<LogEvent> queue = new LinkedBlockingQueue<>();

  private CollectAppender(String name, Filter filter) {
    super(name, filter, null, false, Property.EMPTY_ARRAY);
  }

  @PluginFactory
  public static CollectAppender createAppender(
      @PluginAttribute("name") String name,
      @PluginElement("Filter") Filter filter) {
    return new CollectAppender(name, filter);
  }

  @Override
  public void append(LogEvent event) {
    queue.add( event );
  }
}