@Test
    public void putIfAbsentTest() {
        byte[] key = makeKey("put_if_absent_test");
        byte[] value = makeValue("put_if_absent_test_value");
        TestClosure closure = new TestClosure();
        this.kvStore.putIfAbsent(key, value, closure);
        assertNull(closure.getData());
        this.kvStore.putIfAbsent(key, value, closure);
        assertArrayEquals(value, (byte[]) closure.getData());
    }
Test method: {@link RocksRawKVStore#putIfAbsent(byte[], byte[], KVStoreClosure)}
jraft-rheakv/rheakv-core/src/test/java/com/alipay/sofa/jraft/rhea/storage/rocksdb/RocksKVStoreTest.java