| /* |
| * 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.fluo.core.impl; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.concurrent.BlockingQueue; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.LinkedBlockingQueue; |
| |
| import com.google.common.collect.Collections2; |
| import org.apache.fluo.api.data.Bytes; |
| import org.apache.fluo.api.data.Column; |
| import org.apache.fluo.api.data.RowColumn; |
| |
| public class AsyncReader { |
| private BlockingQueue<AsyncGet> asyncGetsQueue; |
| private ExecutorService executorService; |
| private TransactionImpl tx; |
| |
| public AsyncReader(TransactionImpl tx) { |
| this.tx = tx; |
| asyncGetsQueue = new LinkedBlockingQueue<>(); |
| executorService = Executors.newSingleThreadExecutor(); |
| } |
| |
| public CompletableFuture<Bytes> get(Bytes row, Column column) { |
| return get(row, column, null); |
| } |
| |
| public CompletableFuture<Bytes> get(Bytes row, Column column, Bytes defaultValue) { |
| AsyncGet curAsyncGet = new AsyncGet(row, column, defaultValue); |
| asyncGetsQueue.add(curAsyncGet); |
| |
| executorService.submit(() -> { |
| List<AsyncGet> getsList = new ArrayList<>(); |
| asyncGetsQueue.drainTo(getsList); |
| |
| try { |
| Collection<RowColumn> rowColumns = Collections2.transform(getsList, ag -> ag.rc); |
| |
| Map<RowColumn, Bytes> getsMap = tx.get(rowColumns); |
| |
| for (AsyncGet asyncGet : getsList) { |
| Bytes result = getsMap.get(asyncGet.rc); |
| asyncGet.res.complete(result == null ? asyncGet.defaultValue : result); |
| } |
| } catch (Exception e) { |
| for (AsyncGet asyncGet : getsList) { |
| asyncGet.res.completeExceptionally(e); |
| } |
| } |
| }); |
| |
| return curAsyncGet.res; |
| } |
| |
| public CompletableFuture<String> gets(String row, Column column) { |
| return gets(row, column, null); |
| } |
| |
| public CompletableFuture<String> gets(String row, Column column, String defaultValue) { |
| Bytes defaultValueBytes = defaultValue == null ? new Bytes() : Bytes.of(defaultValue); |
| return get(Bytes.of(row), column, defaultValueBytes).thenApply(b -> b.toString()); |
| } |
| |
| public void close() { |
| executorService.shutdown(); |
| } |
| |
| static class AsyncGet { |
| RowColumn rc; |
| CompletableFuture<Bytes> res; |
| Bytes defaultValue; |
| |
| public AsyncGet(Bytes row, Column column, Bytes defaultValue) { |
| rc = new RowColumn(row, column); |
| res = new CompletableFuture<>(); |
| this.defaultValue = defaultValue; |
| } |
| } |
| } |