Check jedis is connected before executing commands

src/test/java/redis/clients/jedis/tests/JedisTest.java

@@ -0,0 +1,14 @@
+package redis.clients.jedis.tests;
+
+import org.junit.Test;
+
+import redis.clients.jedis.Jedis;
+import redis.clients.jedis.JedisException;
+
+public class JedisTest {
+    @Test(expected = JedisException.class)
+    public void useWithoutConnecting() throws JedisException {
+	Jedis jedis = new Jedis("localhost");
+	jedis.dbSize();
+    }
+}