Java连接redis异常

场景：我在window 10环境中的ecplise中用Jedis连接存在于虚拟机中的redis数据库。redis中的配置文件大部分为默认设置。

源代码：

import redis.clients.jedis.Jedis;

public class TestPing {

public static void main(String[] args) {
Jedis redis = new Jedis("100.100.1.195", 6379);
System.out.println(redis.ping());

}

}

异常1：

Exception in thread "main" redis.clients.jedis.exceptions.JedisConnectionException: java.net.ConnectException: Connection refused: connect
at redis.clients.jedis.Connection.connect(Connection.java:207)
at redis.clients.jedis.BinaryClient.connect(BinaryClient.java:93)
at redis.clients.jedis.Connection.sendCommand(Connection.java:126)
at redis.clients.jedis.Connection.sendCommand(Connection.java:121)
at redis.clients.jedis.BinaryClient.ping(BinaryClient.java:106)
at redis.clients.jedis.BinaryJedis.ping(BinaryJedis.java:195)
at com.study.redis.TestPing.main(TestPing.java:9)

这里出现这个错误的原因有两点：①：防火墙问题，你可以先ping一下，看是否能连通，如果连不通那就是防火墙的问题。可以选择关掉防火墙。②：那是因为redis的默认配置文件中有个设置，只允许本机访问。用vim打开直接输入/bind就会找到。如下图所示，把那个bind 127.0.0.1注释即可：



当你改玩这个之后，它有可能还连不通，会报下面这个错，请继续往下看。

异常2：

Exception in thread "main" redis.clients.jedis.exceptions.JedisDataException: DENIED Redis is running in protected mode because protected mode is enabled, no bind address was specified, no authentication password is requested to clients. In this mode connections are only accepted from the loopback interface. If you want to connect from external computers to Redis you may adopt one of the following solutions: 1) Just disable protected mode sending the command 'CONFIG SET protected-mode no' from the loopback interface by connecting to Redis from the same host the server is running, however MAKE SURE Redis is not publicly accessible from internet if you do so. Use CONFIG REWRITE to make this change permanent. 2) Alternatively you can just disable the protected mode by editing the Redis configuration file, and setting the protected mode option to 'no', and then restarting the server. 3) If you started the server manually just for testing, restart it with the '--protected-mode no' option. 4) Setup a bind address or an authentication password. NOTE: You only need to do one of the above things in order for the server to start accepting connections from the outside.
at redis.clients.jedis.Protocol.processError(Protocol.java:127)
at redis.clients.jedis.Protocol.process(Protocol.java:161)
at redis.clients.jedis.Protocol.read(Protocol.java:215)
at redis.clients.jedis.Connection.readProtocolWithCheckingBroken(Connection.java:340)
at redis.clients.jedis.Connection.getStatusCodeReply(Connection.java:239)
at redis.clients.jedis.BinaryJedis.ping(BinaryJedis.java:196)
at com.study.redis.TestPing.main(TestPing.java:9)

由于redis后期版本加了个保护模式，去配置文件中修改即可，如下图所示：



把那个protected-mode yes 中yes换成no即可，有兴趣可以看一下上面的注释就会明白。

到这，应该就能连通了，控制台ping的回应将会是pong，祝你们好运！