@Override
            public void run(final Status status, final long index, final byte[] reqCtx) {
                assertNull(reqCtx);
                assertTrue(status.isOk());
                latch.countDown();
            }
Test rollback stateMachine with readIndex for issue 317:
https://github.com/sofastack/sofa-jraft/issues/317
jraft-core/src/test/java/com/alipay/sofa/jraft/core/NodeTest.java