1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache license, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. 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 package org.apache.logging.log4j.core.async; 18 19 import com.lmax.disruptor.Sequence; 20 import com.lmax.disruptor.SequenceReportingEventHandler; 21 22 /** 23 * This event handler gets passed messages from the RingBuffer as they become 24 * available. Processing of these messages is done in a separate thread, 25 * controlled by the {@code Executor} passed to the {@code Disruptor} 26 * constructor. 27 */ 28 public class RingBufferLogEventHandler implements 29 SequenceReportingEventHandler<RingBufferLogEvent> { 30 31 private static final int NOTIFY_PROGRESS_THRESHOLD = 50; 32 private Sequence sequenceCallback; 33 private int counter; 34 35 @Override 36 public void setSequenceCallback(final Sequence sequenceCallback) { 37 this.sequenceCallback = sequenceCallback; 38 } 39 40 @Override 41 public void onEvent(final RingBufferLogEvent event, final long sequence, 42 final boolean endOfBatch) throws Exception { 43 event.execute(endOfBatch); 44 event.clear(); 45 46 // notify the BatchEventProcessor that the sequence has progressed. 47 // Without this callback the sequence would not be progressed 48 // until the batch has completely finished. 49 if (++counter > NOTIFY_PROGRESS_THRESHOLD) { 50 sequenceCallback.set(sequence); 51 counter = 0; 52 } 53 } 54 55 }