Added Java code snippets for cuckoo filters (#3679)

* Add CuckooFilterExample

* Add step start comment

* Update CuckooFilterExample.java

---------

Co-authored-by: Ranjeet Singh <ranjeetsingh@192.168.1.7>
Co-authored-by: M Sazzadul Hoque <7600764+sazzad16@users.noreply.github.com>

src/test/java/io/redis/examples/CuckooFilterExample.java

@@ -0,0 +1,45 @@
+// EXAMPLE: cuckoo_tutorial
+
+// HIDE_START
+package io.redis.examples;
+
+import org.junit.Assert;
+import org.junit.Test;
+import redis.clients.jedis.UnifiedJedis;
+
+public class CuckooFilterExample {
+    @Test
+    public void run() {
+        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");
+        // HIDE_END
+
+        // REMOVE_START
+        jedis.del("bikes:models");
+        // REMOVE_END
+
+        // STEP_START cuckoo
+        String res1 = jedis.cfReserve("bikes:models", 1000000);
+        System.out.println(res1); // >>> OK
+
+        // REMOVE_START
+        Assert.assertEquals(res1, "OK");
+        // REMOVE_END
+
+        boolean res2 = jedis.cfAdd("bikes:models", "Smoky Mountain Striker");
+        System.out.println(res2); // >>> True
+
+        boolean res3 = jedis.cfExists("bikes:models", "Smoky Mountain Striker");
+        System.out.println(res3); // >>> True
+
+        boolean res4 = jedis.cfExists("bikes:models", "Terrible Bike Name");
+        System.out.println(res4); // >>> False
+
+        boolean res5 = jedis.cfDel("bikes:models", "Smoky Mountain Striker");
+        System.out.println(res5); // >>> True
+
+        // REMOVE_START
+        Assert.assertTrue(res5);
+        // REMOVE_END
+        // STEP_END
+    }
+}