| /** |
| * 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.distributedlog.limiter; |
| |
| |
| import com.google.common.base.Stopwatch; |
| import com.google.common.collect.ImmutableList; |
| import java.util.concurrent.TimeUnit; |
| import org.apache.bookkeeper.stats.NullStatsLogger; |
| import org.apache.bookkeeper.stats.OpStatsLogger; |
| import org.apache.bookkeeper.stats.StatsLogger; |
| import org.apache.distributedlog.exceptions.OverCapacityException; |
| |
| |
| |
| |
| /** |
| * Chain request limiters for easier management of multi limiter policy. |
| */ |
| public class ChainedRequestLimiter<Request> implements RequestLimiter<Request> { |
| private final ImmutableList<RequestLimiter<Request>> limiters; |
| private final OpStatsLogger applyTime; |
| |
| /** |
| * Builder to build ChainedRequestLimiter. |
| */ |
| public static class Builder<Request> { |
| private final ImmutableList.Builder<RequestLimiter<Request>> limitersBuilder; |
| private StatsLogger statsLogger = NullStatsLogger.INSTANCE; |
| |
| public Builder() { |
| this.limitersBuilder = new ImmutableList.Builder<RequestLimiter<Request>>(); |
| } |
| |
| public Builder<Request> addLimiter(RequestLimiter<Request> limiter) { |
| this.limitersBuilder.add(limiter); |
| return this; |
| } |
| |
| public Builder<Request> statsLogger(StatsLogger statsLogger) { |
| this.statsLogger = statsLogger; |
| return this; |
| } |
| |
| public ChainedRequestLimiter<Request> build() { |
| return new ChainedRequestLimiter<Request>(limitersBuilder.build(), statsLogger); |
| } |
| } |
| |
| private ChainedRequestLimiter(ImmutableList<RequestLimiter<Request>> limiters, |
| StatsLogger statsLogger) { |
| this.limiters = limiters; |
| this.applyTime = statsLogger.getOpStatsLogger("apply"); |
| } |
| |
| public void apply(Request request) throws OverCapacityException { |
| Stopwatch stopwatch = Stopwatch.createStarted(); |
| try { |
| for (RequestLimiter<Request> limiter : limiters) { |
| limiter.apply(request); |
| } |
| } finally { |
| applyTime.registerSuccessfulEvent(stopwatch.elapsed(TimeUnit.MICROSECONDS), TimeUnit.MICROSECONDS); |
| } |
| } |
| } |