RedisTemplate keys(String pattern) method is giving empty set

Using org.springframework.data.redis.core.RedisTemplate for storing data in redis server. I have the keys in pattern similar to "abc@xyz@pqr". Wanted to get all the keys which have the starting letters as "abc", and was using RedisTemplate.keys(String pattern) method for the same as Below:

Set<String> redisKeys = redisTemplate.keys("(abc).*");

for (String key : redisKeys) {
    System.out.println(key);
}

But its always giving me empty set.

// tried this pattern also 
Set<String> redisKeys = redisTemplate.keys("abc*");

Please help me out.