com.epam.deltix.util.ContextContainer Maven / Gradle / Ivy

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/*
 * Copyright 2023 EPAM Systems, Inc
 *
 * See the NOTICE file distributed with this work for additional information
 * regarding copyright ownership. Licensed 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 com.epam.deltix.util;

import com.google.common.annotations.VisibleForTesting;
import com.epam.deltix.thread.affinity.AffinityConfig;
import com.epam.deltix.util.concurrent.QuickExecutor;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import javax.annotation.ParametersAreNonnullByDefault;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * @author Alexei Osipov
 */
@ParametersAreNonnullByDefault
// TODO: rename to ThreadExecutor and move to util

public class ContextContainer {
    private static final AtomicInteger namelessExecutorIndex = new AtomicInteger();
    private static final AtomicInteger testExecutorIndex = new AtomicInteger();

    private volatile AffinityConfig affinityConfig = getDefaultAffinityConfig();

    private volatile String quickExecutorName = null;
    private volatile QuickExecutor quickExecutor = null;

    @Nullable
    public AffinityConfig getAffinityConfig() {
        return affinityConfig;
    }

    public void setAffinityConfig(@Nullable AffinityConfig affinityConfig) {
        this.affinityConfig = affinityConfig;
    }

    @Nonnull
    public QuickExecutor getQuickExecutor() {
        // Lazy singleton
        if (this.quickExecutor == null) {
            synchronized (QuickExecutor.class) {
                if (this.quickExecutor == null) {
                    this.quickExecutor = createQuickExecutor();
                }
            }
        }
        return this.quickExecutor;
    }

    /**
     * Marks QuickExecutor for shutdown. Tries to avoid executor creation.
     */
    public void shutdownQuickExecutor() {
        // Note: current implementation DOES breaks instance creation check.
        if (this.quickExecutor == null) {
            return;
        }
        getQuickExecutor().shutdownInstance();
    }

    @Nonnull
    private QuickExecutor createQuickExecutor() {
        String name = this.quickExecutorName;
        if (name == null) {
            name = "ContextContainer Executor #" + namelessExecutorIndex.incrementAndGet();
        }
        return QuickExecutor.createNewInstance(name, this.affinityConfig);
    }

    public void setQuickExecutorName(String quickExecutorName) {
        this.quickExecutorName = quickExecutorName;
    }


    @VisibleForTesting
    public static ContextContainer getContextContainerForClientTests() {
        ContextContainer contextContainer = new ContextContainer();
        contextContainer.setQuickExecutorName("Client Test Executor #" + testExecutorIndex.incrementAndGet());
        return contextContainer;
    }

    @VisibleForTesting
    public static ContextContainer getContextContainerForServerTests() {
        ContextContainer contextContainer = new ContextContainer();
        contextContainer.setQuickExecutorName("Server Test Executor #" + testExecutorIndex.incrementAndGet());
        return contextContainer;
    }

    private static AffinityConfig getDefaultAffinityConfig() {
        // Null value mean no any explicit affinity
        return null;
    }
}