org.jobrunr.server.threadpool.VirtualThreadJobRunrExecutor Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jobrunr Show documentation
An easy way to perform background processing on the JVM. Backed by persistent storage. Open and free for commercial use.
There is a newer version: 7.3.1
Show newest version
package org.jobrunr.server.threadpool;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.lang.reflect.Method;
import java.time.Duration;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.TimeUnit;

import static org.jobrunr.utils.reflection.ReflectionUtils.findMethod;

public class VirtualThreadJobRunrExecutor implements JobRunrExecutor {

    private static final Logger LOGGER = LoggerFactory.getLogger(VirtualThreadJobRunrExecutor.class);

    private final ExecutorService executorService;
    private final int workerCount;
    private boolean started;
    private boolean isStopping;

    public VirtualThreadJobRunrExecutor(int workerCount) {
        this(workerCount, "backgroundjob-worker");
    }

    public VirtualThreadJobRunrExecutor(int workerCount, String name) {
        this(workerCount, createVirtualThreadExecutorService(name));
    }

    public VirtualThreadJobRunrExecutor(int workerCount, ExecutorService executorService) {
        this.workerCount = workerCount;
        this.executorService = executorService;
    }

    @Override
    public int getWorkerCount() {
        return workerCount;
    }

    @Override
    public void start() {
        this.started = true;
        LOGGER.info("ThreadManager of type 'VirtualThreadPerTask' started");
    }

    @Override
    public void stop(Duration awaitTimeout) {
        this.isStopping = true;
        this.started = false;
        executorService.shutdown();
        try {
            if (!executorService.awaitTermination(awaitTimeout.getSeconds(), TimeUnit.SECONDS)) {
                executorService.shutdownNow();
            }
        } catch (InterruptedException e) {
            executorService.shutdownNow();
            Thread.currentThread().interrupt(); // Preserve interrupt status
        }
    }

    @Override
    public boolean isStopping() {
        return isStopping;
    }

    @Override
    public void execute(Runnable command) {
        if (started) {
            executorService.submit(command);
        }
    }

    static ExecutorService createVirtualThreadExecutorService(String name) {
        try {
            Method virtualThreadBuilderMethod = findMethod(Thread.class, "ofVirtual").orElseThrow(() -> new NoSuchMethodException("java.lang.Thread.ofVirtual()"));
            Object virtualThreadBuilder = virtualThreadBuilderMethod.invoke(null);

            Method nameVirtualThreadBuilderMethod = findMethod(virtualThreadBuilderMethod.getReturnType(), "name", String.class).orElseThrow(() -> new NoSuchMethodException("java.lang.Thread.Builder.OfVirtual.name(java.lang.String)"));
            virtualThreadBuilder = nameVirtualThreadBuilderMethod.invoke(virtualThreadBuilder, name);

            Method factoryVirtualThreadBuilderMethod = findMethod(Class.forName("java.lang.Thread$Builder"), "factory").orElseThrow(() -> new NoSuchMethodException("java.lang.Thread.Builder.OfVirtual.factory()"));
            ThreadFactory factory = (ThreadFactory) factoryVirtualThreadBuilderMethod.invoke(virtualThreadBuilder);
            Method newThreadPerTaskExecutorMethod = findMethod(Executors.class, "newThreadPerTaskExecutor", ThreadFactory.class).orElseThrow(() -> new NoSuchMethodException("java.util.concurrent.Executors.newThreadPerTaskExecutor(java.util.concurrent.ThreadFactory)"));
            return (ExecutorService) newThreadPerTaskExecutorMethod.invoke(null, factory);
        } catch (ReflectiveOperationException e) {
            throw new IllegalStateException("Could not create VirtualThreadJobRunrExecutor on Java " + System.getProperty("java.version"), e);
        }
    }
}