001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.regionserver.wal; 019 020import static org.apache.hadoop.hbase.util.FutureUtils.addListener; 021 022import java.util.concurrent.CompletableFuture; 023import java.util.concurrent.atomic.AtomicInteger; 024import org.apache.hadoop.hbase.wal.WAL.Entry; 025import org.apache.hadoop.hbase.wal.WALProvider.AsyncWriter; 026import org.apache.yetus.audience.InterfaceAudience; 027 028import org.apache.hbase.thirdparty.com.google.common.collect.ImmutableList; 029 030/** 031 * An {@link AsyncWriter} wrapper which writes data to a set of {@link AsyncWriter} instances. 032 */ 033@InterfaceAudience.Private 034public final class CombinedAsyncWriter extends CombinedWriterBase<AsyncWriter> 035 implements AsyncWriter { 036 037 private CombinedAsyncWriter(ImmutableList<AsyncWriter> writers) { 038 super(writers); 039 } 040 041 @Override 042 public void append(Entry entry) { 043 writers.forEach(w -> w.append(entry)); 044 } 045 046 @Override 047 public CompletableFuture<Long> sync(boolean forceSync) { 048 CompletableFuture<Long> future = new CompletableFuture<>(); 049 AtomicInteger remaining = new AtomicInteger(writers.size()); 050 writers.forEach(w -> addListener(w.sync(forceSync), (length, error) -> { 051 if (error != null) { 052 future.completeExceptionally(error); 053 return; 054 } 055 if (remaining.decrementAndGet() == 0) { 056 future.complete(length); 057 } 058 })); 059 return future; 060 } 061 062 public static CombinedAsyncWriter create(AsyncWriter writer, AsyncWriter... writers) { 063 return new CombinedAsyncWriter( 064 ImmutableList.<AsyncWriter> builder().add(writer).add(writers).build()); 065 } 066}