c5db.ConcurrencyTestUtil.java Source code

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Here is the source code for c5db.ConcurrencyTestUtil.java

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/*
 * Copyright 2014 WANdisco
 *
 *  WANdisco 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 c5db;

import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.SettableFuture;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

/**
 * Utilities for running concurrency tests.
 */
public class ConcurrencyTestUtil {

    public static void runAConcurrencyTestSeveralTimes(int numThreads, int numAttempts, ConcurrencyTest test)
            throws Exception {
        final ExecutorService taskSubmitter = Executors.newFixedThreadPool(numThreads);

        for (int attempt = 0; attempt < numAttempts; attempt++) {
            test.run(numThreads * 2, taskSubmitter);
        }

        taskSubmitter.shutdown();
        taskSubmitter.awaitTermination(10, TimeUnit.SECONDS);
    }

    public static void runNTimesAndWaitForAllToComplete(int nTimes, ExecutorService executor,
            IndexedExceptionThrowingRunnable runnable) throws Exception {
        final List<ListenableFuture<Boolean>> completionFutureList = new ArrayList<>(nTimes);

        for (int i = 0; i < nTimes; i++) {
            completionFutureList.add(runAndReturnCompletionFuture(executor, runnable, i));
        }

        waitForAll(completionFutureList);
    }

    public static void runNTimesAndWaitForAllToComplete(int nTimes, ExecutorService executor,
            ExceptionThrowingRunnable runnable) throws Exception {
        runNTimesAndWaitForAllToComplete(nTimes, executor, (int ignore) -> runnable.run());
    }

    private static ListenableFuture<Boolean> runAndReturnCompletionFuture(ExecutorService executor,
            IndexedExceptionThrowingRunnable runnable, int invocationIndex) {
        final SettableFuture<Boolean> setWhenFinished = SettableFuture.create();

        executor.execute(() -> {
            try {
                runnable.run(invocationIndex);
                setWhenFinished.set(true);
            } catch (Throwable t) {
                setWhenFinished.setException(t);
            }
        });
        return setWhenFinished;
    }

    private static void waitForAll(List<ListenableFuture<Boolean>> futures) throws Exception {
        Futures.allAsList(futures).get();
    }

    public interface ConcurrencyTest {
        void run(int degreeOfConcurrency, ExecutorService executorService) throws Exception;
    }

    public interface IndexedExceptionThrowingRunnable {
        void run(int indexIdentifyingThisInvocation) throws Exception;
    }

    public interface ExceptionThrowingRunnable {
        void run() throws Exception;
    }
}