Java调用Redis集群代码及问题解决

<dependency>
  <groupId>org.apache.commons</groupId>
  <artifactId>commons-pool2</artifactId>
  <version>2.6.2</version>
</dependency>
 
<dependency>
  <groupId>redis.clients</groupId>
  <artifactId>jedis</artifactId>
  <version>3.0.1</version>
</dependency>
 
<dependency>
  <groupId>org.slf4j</groupId>
  <artifactId>slf4j-api</artifactId>
  <version>1.7.26</version>
</dependency>
 
<dependency>
  <groupId>org.slf4j</groupId>
  <artifactId>slf4j-simple</artifactId>
  <version>1.7.26</version>
  <scope>test</scope>
</dependency>

package Main;
import java.io.IOException;
import java.util.LinkedHashSet;
import java.util.Set;
import redis.clients.jedis.HostAndPort;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisCluster;
import redis.clients.jedis.JedisPoolConfig;
@SuppressWarnings("all")
public class RedisMain {
   public static void main(String[] args) {
     JedisCluster cluster =null;
     try {       
        Set<HostAndPort> nodes = new LinkedHashSet<HostAndPort>();
        //一般选用slaveof从IP+端口进行增删改查，不用master
        nodes.add(new HostAndPort("外网IP", 7003));
        nodes.add(new HostAndPort("外网", 7004));
        nodes.add(new HostAndPort("外网IP", 7004));
        // Jedis连接池配置
        JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
        // 最大空闲连接数, 默认8个
        jedisPoolConfig.setMaxIdle(100);
        // 最大连接数, 默认8个
        jedisPoolConfig.setMaxTotal(500);
        //最小空闲连接数, 默认0
        jedisPoolConfig.setMinIdle(0);
        // 获取连接时的最大等待毫秒数(如果设置为阻塞时BlockWhenExhausted),如果超时就抛异常, 小于零:阻塞不确定的时间, 默认-1
        jedisPoolConfig.setMaxWaitMillis(2000); // 设置2秒
        //对拿到的connection进行validateObject校验
        jedisPoolConfig.setTestOnBorrow(true);
        //未设置auth Password
        JedisCluster jedis = new JedisCluster(nodes, jedisPoolConfig);
        //设置auth Password
        //JedisCluster jedis = new JedisCluster(nodes,5000,3000,10,{auth_password}, new JedisPoolConfig());
        System.out.println(jedis.get("mykey"));       
     }catch(Exception e) {
       e.printStackTrace();
     }finally {
       if(null !=cluster)
         cluster.close();
     }
   }
}