@domenico
You cannot directly add a Java HashMap object into Redis, as Redis is a key-value store that only accepts string values. However, you can serialize the HashMap object into a JSON string and then store it in Redis using a specific key.
Here is an example of how you can add a HashMap into Redis using Jedis, a popular Java client for Redis:
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import redis.clients.jedis.Jedis; import com.google.gson.Gson; import java.util.HashMap; public class RedisExample { public static void main(String[] args) { Jedis jedis = new Jedis("localhost"); // Create a HashMap HashMap<String, String> map = new HashMap<>(); map.put("key1", "value1"); map.put("key2", "value2"); // Serialize the HashMap into a JSON string Gson gson = new Gson(); String json = gson.toJson(map); // Store the JSON string in Redis jedis.set("myHashMap", json); // Retrieve the HashMap from Redis String jsonFromRedis = jedis.get("myHashMap"); HashMap<String, String> mapFromRedis = gson.fromJson(jsonFromRedis, HashMap.class); // Print the HashMap retrieved from Redis System.out.println(mapFromRedis); jedis.close(); } } |
In this example, we first create a HashMap object and serialize it into a JSON string using the Gson library. Next, we store this JSON string in Redis with the key "myHashMap". Finally, we retrieve the JSON string from Redis, deserialize it back into a HashMap object, and print it out.