@Override
    public void rejectedExecution(final Runnable r, final ThreadPoolExecutor e) {
        LOG.error("Thread pool [{}] is exhausted! {}.", threadPoolName, e.toString());

        dumpJvmInfoIfNeeded();

        if (!e.isShutdown()) {
            r.run();
        }
    }
A handler for rejected tasks that use the caller-runs policy,
not discard task, not throw exception, let caller thread to
execute the task.

@author jiachun.fjc
jraft-rheakv/rheakv-core/src/main/java/com/alipay/sofa/jraft/rhea/util/concurrent/CallerRunsPolicyWithReport.java