private void getAndPutTest(RheaKVStore store) {
        // regions: 1 -> [null, g), 2 -> [g, null)
        byte[] key = makeKey("put_test");
        checkRegion(store, key, 2);
        byte[] value = store.bGet(key);
        assertNull(value);

        value = makeValue("put_test_value");
        byte[] preVal = store.bGetAndPut(key, value);
        assertNull(preVal);
        byte[] newVal = makeValue("put_test_value_new");
        preVal = store.bGetAndPut(key, newVal);
        assertArrayEquals(value, preVal);
    }
Test method: {@link RheaKVStore#getAndPut(byte[], byte[])}
jraft-rheakv/rheakv-core/src/test/java/com/alipay/sofa/jraft/rhea/storage/rhea/AbstractRheaKVStoreTest.java