- Redis is an open source, advanced key-value store that can store different data structures like strings, hashes, lists, sets and sorted sets. - Jedis is the recommended Redis client library for Java. It can be used to connect to Redis and execute commands to set, get, and manipulate Redis data structures. - The document provides examples of common Redis commands to work with strings, lists, sets, sorted sets, hashes, publish/subscribe and more using the Jedis client.

2. What is Redis?
• Redis is an open source, advanced key-value store. It is often referred to as a data
structure server since keys can contain strings, hashes, lists, sets and sorted sets.
http://redis.io

3. What is Jedis?
• Redis recommended client is Jedis.
• Available at https://github.com/xetorthio/jedis/wiki/Getting-started
Maven dependency
<dependency>
Setting up the Pool <groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
private void setupPool(){ <version>2.0.0</version>
try{ <type>jar</type>
pool = new JedisPool(new JedisPoolConfig(), HOST, PORT, <scope>compile</scope>
poolTimeout) ; </dependency>
jedis = pool.getResource();
System.out.println("Redis Client is connection to: " + HOST + ":" +
PORT) ;
jedis.auth("foobared");
jedis.configSet("timeout", "500");
jedis.connect();
jedis.flushAll();
}catch(Exception ex){
ex.printStackTrace();
}
}
http://redis.io/clients git clone git://github.com/xetorthio/jedis.git

4. Installation
Download, extract and compile Redis with:
$ wget http://redis.googlecode.com/files/redis-2.4.13.tar.gz
$ tar xzf redis-2.4.13.tar.gz
$ cd redis-2.4.13
$ make

5. Basic Usage- Strings
$ src/redis-cli
redis> set foo bar
OK
redis> get foo
"bar"

6. Basic Usage- Strings
APPEND – Make a string longer
GET – Fetch a string at key
GETRANGE – Fetch a substring of key's value
GETSET – Get and Set in one operation
MGET – Multiple Gets
MSET – Multiple Sets
MSETNX – SET Multiple if Not eXists
SET – SET a value if not exists
SETEX – SET a value that EXpires
SETNX – Set if Not eXists
SETRANGE – Rewrite a substring
STRLEN – Integer length of string

7. Basic Usage- More with Strings
INCR, INCRBY, DECR, DECRBY,
Atomic Counters!
Atomic operation - prevents any
other processor or I/O device from
writing or reading memory until
the operation is complete.

8. More with Strings
In fact, all of the built-in
commands of Redis are atomic.
And they can be chained together
(pipelined) to create complex
atomic transactions.

9. Command Line Interface
Basic Usage – Keys
redis> keys b*
1) "baz"
2) "bar"
(Use sparingly, though; keys is expensive.)

10. Basic Usage - Lists
redis> LPUSH mylist "world"
public void lPushListTest(String queueName,
(integer) 1
String value){
redis> LPUSH mylist "hello"
try{
(integer) 2
jedis.lpush(queueName, value) ;
// [ 'world', 'hello' ]
}catch(Exception ex){
redis> LRANGE mylist 0 -1
ex.printStackTrace();
1) "hello"
}
2) "world"
}
public void lPopList(String queueName){
while(jedis.llen(queueName) != 0 ){
String item = jedis.lpop(queueName);
}
}

11. Basic Usage - Lists
LINDEX – Return the list item at a certain position
LINSERT – Insert item into list BEFORE|AFTER item
LLEN – Number of list items (length)
LRANGE – Return some of the items
LREM – Remove one or more items
LSET – Sets the list element at index to value
LTRIM – Lop off some items
LPOP, LPUSH, LPUSHX – Left pop/push
RPOP, RPUSH, RPUSHX, RPOPLPUSH – Right pop/push
BLPOP, BRPOP, BRPOPLPUSH – Blocking pop/push

12. Basic Usage - Sets
redis> SADD myset "Hello"
(integer) 1
redis> SADD myset "World"
(integer) 1
redis> SADD myset "World" public void sAdd(String key, String member)
(integer) 0
redis> SMEMBERS myset throws Exception {
1) "World" 2) "Hello“ Jedis jedis = null;
redis> try{
jedis = (Jedis) getJedisInstance() ;
jedis.sadd(key, member);
}catch(Exception ex){
ex.printStackTrace();
}finally{
returnJedisInstance(jedis);
getLog( getClass()
).logInfo("returnJedisInstance");
}
}

13. Basic Usage - Sets
SADD – Add a member to a set
SCARD – Set CARDinality – Number of set members
SDIFF – Calculate difference between 2 sets
SDIFFSTORE – Store the Difference of 2 sets in a set
SINTER – Calculate the intersection between 2 sets
SINTERSTORE – Store the intersection of 2 sets in a set
SISMEMBER – Bool test whether X is a member of set S
SMEMBERS – list out all the members
SMOVE – Move a member from a set to another set
SPOP – Pop a member off from a set
SRANDMEMBER – Fetch a random set member
SREM – Remove a member from the set
SUNION – Merge two sets together
SUNIONSTORE – Store the merger of two sets in a set

14. Basic Usage - Hashes
redis> HMSET myhash field1 "Hello" field2 "World"
OK
redis> HGET myhash field1
"Hello“
redis> HGET myhash field2
"World"
redis>
public void hSetTest(String queueName,
String key, String value){
try{
jedis.hsetnx(queueName, key, value) ;
}catch(Exception ex){
ex.printStackTrace();
}
}

15. Basic Usage - Hashes
HDEL – Delete a field & value from a hash
HEXISTS – Bool test whether field is in hash
HGET – fetch value stored under hash → field
HGETALL – fetch the whole hash
HINCRBY – Increment a value stored under a hash field
HKEYS – keys as a set → array_keys( )
HLEN – Integer – Number of fields stored in hash
HMGET – Array – Fetch multiple fields from hash
HMSET – Set multiple fields in a hash
HSET – Set one field in a hash
HSETNX – Set a hash field if it doesn't exist
HVALS – vals as a list → array_values( )

16. Basic Usage - Sorted Sets
redis> ZADD myzset 1 "one“
(integer) 1
redis> ZADD myzset 1 "uno"
(integer) 1
redis> ZADD myzset 2 "two" public void zAdd(String key, Sting score, String
(integer) 1
redis> ZADD myzset 3 "two" member) throws Exception {
(integer) 0 Jedis jedis = null;
redis> ZRANGE myzset 0 -1 try{
WITHSCORES jedis = (Jedis) getJedisInstance() ;
1) "one“
2) "1" jedis.zadd(key, score, member);
3) "uno"
4) "1" }catch(Exception ex){
5) "two"
6) "3"
ex.printStackTrace();
redis> }finally{
returnJedisInstance(jedis);
getLog( getClass()
).logInfo("returnJedisInstance");
}
}

17. Basic Usage - Sorted Sets
ZADD – Add a member to a set with a score
ZCARD – Count how many members are in the sorted set
ZCOUNT – Count how many elemenents between 2 scores
ZINCRBY – Increase/Decrease a member's score
ZINTERSTORE – Intersect on scores and store it
ZRANGE – Return some members between 2 indexes
ZRANGEBYSCORE – Return some members between 2 scores
ZRANK – Returns a member index from Lo to Hi
ZREM – Remove a sorted set's member
ZREMRANGEBYRANK – Remove some members by rank
ZREMRANGEBYSCORE – Remove some members by score
ZREVRANGE – Fetch members by index in desc order
ZREVRANGEBYSCORE – Fetch members by score in desc order
ZREVRANK – Returns the index from Hi to Lo
ZSCORE – Fetch the score of a member
ZUNIONSTORE – Merge 2 sorted sets into a 3rd sorted set

18. Basic Usage- Pub/Sub
redis>
redis> subscribe foo
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) “foo"
3) (integer) 1

19. Basic Usage- Pub/Sub
redis>publish foo test
(integer) 1
redis> subscribe foo
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) “foo"
3) (integer) 1
1) "message"
2) “foo"
3) “test"

20. Basic Usage- Pub/Sub
public void publishMessage(String channel,
String message){
try{
jedis.publish(channel, message);
}catch(Exception ex){
ex.printStackTrace();
}
}
public void subscribeChannels(String channel1, String channel2){
try{
jedis.subscribe(this, channel1, channel2);
System.out.println("sub.getSubscribedChannels();" +
this.getSubscribedChannels());
}catch(Exception ex){
ex.printStackTrace();
}
}

21. Utilities
public void flushAllQueue(){
try{
jedis.flushAll();
jedis.flushDB();
}catch(Exception ex){
ex.printStackTrace();
}
}
public void saveQueueToDisk(){
jedis.save();
}