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 */ 017package org.apache.logging.log4j.core.async; 018 019import com.lmax.disruptor.Sequence; 020import com.lmax.disruptor.SequenceReportingEventHandler; 021 022/** 023 * This event handler gets passed messages from the RingBuffer as they become 024 * available. Processing of these messages is done in a separate thread, 025 * controlled by the {@code Executor} passed to the {@code Disruptor} 026 * constructor. 027 */ 028public class RingBufferLogEventHandler implements 029 SequenceReportingEventHandler<RingBufferLogEvent> { 030 031 private static final int NOTIFY_PROGRESS_THRESHOLD = 50; 032 private Sequence sequenceCallback; 033 private int counter; 034 035 @Override 036 public void setSequenceCallback(final Sequence sequenceCallback) { 037 this.sequenceCallback = sequenceCallback; 038 } 039 040 @Override 041 public void onEvent(final RingBufferLogEvent event, final long sequence, 042 final boolean endOfBatch) throws Exception { 043 event.execute(endOfBatch); 044 event.clear(); 045 046 // notify the BatchEventProcessor that the sequence has progressed. 047 // Without this callback the sequence would not be progressed 048 // until the batch has completely finished. 049 if (++counter > NOTIFY_PROGRESS_THRESHOLD) { 050 sequenceCallback.set(sequence); 051 counter = 0; 052 } 053 } 054 055}