CompletableFuture.supplyAsync在jdk11下的坑

CompletableFuture.supplyAsync 使用的线程池在默认情况下是 jdk 的 ForkJoinPool.common。

在jdk11的情况下该类创建的线程使用的classLoader是SystemClassLoader，这会造成一些场景下需要在该线程中动态加载业务类的话，会出现class not found。

解决方式就是不使用jdk默认提供的ForkJoin线程池。

private static final Executor executor =
            new ForkJoinPool(Runtime.getRuntime().availableProcessors(), new DefaultForkJoinWorkerThreadFactory(), null, false);

    private static final class DefaultForkJoinWorkerThreadFactory
            implements ForkJoinPool.ForkJoinWorkerThreadFactory {

        @Override
        public final ForkJoinWorkerThread newThread(ForkJoinPool pool) {
            return new CustomerForkJoinWorkerThread(pool);
        }

        private static class CustomerForkJoinWorkerThread extends ForkJoinWorkerThread {

            private CustomerForkJoinWorkerThread(final ForkJoinPool pool) {
                super(pool);
                // set the correct classloader here
                setContextClassLoader(Thread.currentThread().getContextClassLoader());
            }
        }

    }


CompletableFuture.supplyAsync(() -> {
            你的业务逻辑
        }, executor);