redis.clients.jedis
Class Jedis

java.lang.Object
  redis.clients.jedis.Jedis

public class Jedis
extends Object

Constructor Summary

Jedis(JedisShardInfo shardInfo)

Jedis(String host)

Jedis(String host, int port)

Jedis(String host, int port, int timeout)

Method Summary

Integer	append(String key, String value) If the key already exists and is a string, this command appends the provided value at the end of the string.
String	auth(String password) Request for authentication in a password protected Redis server.
String	bgrewriteaof() Rewrite the append only file in background when it gets too big.
String	bgsave() Asynchronously save the DB on disk.
List<String>	blpop(int timeout, String... keys) BLPOP (and BRPOP) is a blocking list pop primitive.
List<String>	brpop(int timeout, String... keys) BLPOP (and BRPOP) is a blocking list pop primitive.
List<String>	configGet(String pattern) Retrieve the configuration of a running Redis server.
String	configSet(String parameter, String value) Alter the configuration of a running Redis server.
void	connect()
Integer	dbSize() Return the number of keys in the currently selected database.
String	debug(DebugParams params)
Integer	decr(String key) Decrement the number stored at key by one.
Integer	decrBy(String key, int integer) IDECRBY work just like INCR but instead to decrement by 1 the decrement is integer.
Integer	del(String... keys) Remove the specified keys.
void	disconnect()
String	echo(String string)
Integer	exists(String key) Test if the specified key exists.
Integer	expire(String key, int seconds) Set a timeout on the specified key.
Integer	expireAt(String key, long unixTime) EXPIREAT works exctly like EXPIRE but instead to get the number of seconds representing the Time To Live of the key as a second argument (that is a relative way of specifing the TTL), it takes an absolute one in the form of a UNIX timestamp (Number of seconds elapsed since 1 Gen 1970).
String	flushAll() Delete all the keys of all the existing databases, not just the currently selected one.
String	flushDB() Delete all the keys of the currently selected DB.
String	get(String key) Get the value of the specified key.
String	getSet(String key, String value) GETSET is an atomic set this value and return the old value command.
Integer	hdel(String key, String field) Remove the specified field from an hash stored at key.
Integer	hexists(String key, String field) Test for existence of a specified field in a hash.
String	hget(String key, String field) If key holds a hash, retrieve the value associated to the specified field.
Map<String,String>	hgetAll(String key) Return all the fields and associated values in a hash.
Integer	hincrBy(String key, String field, int value) Increment the number stored at field in the hash at key by value.
List<String>	hkeys(String key) Return all the fields in a hash.
Integer	hlen(String key) Return the number of items in a hash.
List<String>	hmget(String key, String... fields) Retrieve the values associated to the specified fields.
String	hmset(String key, Map<String,String> hash) Set the respective fields to the respective values.
Integer	hset(String key, String field, String value) Set the specified hash field to the specified value.
Integer	hsetnx(String key, String field, String value) Set the specified hash field to the specified value if the field not exists.
List<String>	hvals(String key) Return all the values in a hash.
Integer	incr(String key) Increment the number stored at key by one.
Integer	incrBy(String key, int integer) INCRBY work just like INCR but instead to increment by 1 the increment is integer.
String	info() Provide information and statistics about the server.
boolean	isConnected()
List<String>	keys(String pattern) Returns all the keys matching the glob-style pattern as space separated strings.
Integer	lastsave() Return the UNIX time stamp of the last successfully saving of the dataset on disk.
String	lindex(String key, int index) Return the specified element of the list stored at the specified key.
Integer	linsert(String key, Client.LIST_POSITION where, String pivot, String value)
Integer	llen(String key) Return the length of the list stored at the specified key.
String	lpop(String key) Atomically return and remove the first (LPOP) or last (RPOP) element of the list.
Integer	lpush(String key, String string) Add the string value to the head (LPUSH) or tail (RPUSH) of the list stored at key.
Integer	lpushx(String key, String string)
List<String>	lrange(String key, int start, int end) Return the specified elements of the list stored at the specified key.
Integer	lrem(String key, int count, String value) Remove the first count occurrences of the value element from the list.
String	lset(String key, int index, String value) Set a new value as the element at index position of the List at key.
String	ltrim(String key, int start, int end) Trim an existing list so that it will contain only the specified range of elements specified.
List<String>	mget(String... keys) Get the values of all the specified keys.
void	monitor(JedisMonitor jedisMonitor) Dump all the received requests in real time.
Integer	move(String key, int dbIndex) Move the specified key from the currently selected DB to the specified destination DB.
String	mset(String... keysvalues) Set the the respective keys to the respective values.
Integer	msetnx(String... keysvalues) Set the the respective keys to the respective values.
Transaction	multi()
List<Object>	multi(TransactionBlock jedisTransaction)
Integer	persist(String key) Undo a expire at turning the expire key into a normal key.
String	ping()
List<Object>	pipelined(JedisPipeline jedisPipeline)
void	psubscribe(JedisPubSub jedisPubSub, String... patterns)
Integer	publish(String channel, String message)
void	quit() Ask the server to silently close the connection.
String	randomKey() Return a randomly selected key from the currently selected DB.
String	rename(String oldkey, String newkey) Atomically renames the key oldkey to newkey.
Integer	renamenx(String oldkey, String newkey) Rename oldkey into newkey but fails if the destination key newkey already exists.
String	rpop(String key) Atomically return and remove the first (LPOP) or last (RPOP) element of the list.
String	rpoplpush(String srckey, String dstkey) Atomically return and remove the last (tail) element of the srckey list, and push the element as the first (head) element of the dstkey list.
Integer	rpush(String key, String string) Add the string value to the head (LPUSH) or tail (RPUSH) of the list stored at key.
Integer	rpushx(String key, String string)
Integer	sadd(String key, String member) Add the specified member to the set value stored at key.
String	save() Synchronously save the DB on disk.
Integer	scard(String key) Return the set cardinality (number of elements).
Set<String>	sdiff(String... keys) Return the difference between the Set stored at key1 and all the Sets key2, ..., keyN
Integer	sdiffstore(String dstkey, String... keys) This command works exactly like SDIFF but instead of being returned the resulting set is stored in dstkey.
String	select(int index) Select the DB with having the specified zero-based numeric index.
String	set(String key, String value) Set the string value as value of the key.
String	setex(String key, int seconds, String value) The command is exactly equivalent to the following group of commands: SET + EXPIRE.
Integer	setnx(String key, String value) SETNX works exactly like SET with the only difference that if the key already exists no operation is performed.
String	shutdown() Synchronously save the DB on disk, then shutdown the server.
Set<String>	sinter(String... keys) Return the members of a set resulting from the intersection of all the sets hold at the specified keys.
Integer	sinterstore(String dstkey, String... keys) This commnad works exactly like SINTER but instead of being returned the resulting set is sotred as dstkey.
Integer	sismember(String key, String member) Return 1 if member is a member of the set stored at key, otherwise 0 is returned.
String	slaveof(String host, int port) Change the replication settings.
String	slaveofNoOne()
Set<String>	smembers(String key) Return all the members (elements) of the set value stored at key.
Integer	smove(String srckey, String dstkey, String member) Move the specifided member from the set at srckey to the set at dstkey.
List<String>	sort(String key) Sort a Set or a List.
List<String>	sort(String key, SortingParams sortingParameters) Sort a Set or a List accordingly to the specified parameters.
Integer	sort(String key, SortingParams sortingParameters, String dstkey) Sort a Set or a List accordingly to the specified parameters and store the result at dstkey.
Integer	sort(String key, String dstkey) Sort a Set or a List and Store the Result at dstkey.
String	spop(String key) Remove a random element from a Set returning it as return value.
String	srandmember(String key) Return a random element from a Set, without removing the element.
Integer	srem(String key, String member) Remove the specified member from the set value stored at key.
Integer	strlen(String key)
void	subscribe(JedisPubSub jedisPubSub, String... channels)
String	substr(String key, int start, int end) Return a subset of the string from offset start to offset end (both offsets are inclusive).
Set<String>	sunion(String... keys) Return the members of a set resulting from the union of all the sets hold at the specified keys.
Integer	sunionstore(String dstkey, String... keys) This command works exactly like SUNION but instead of being returned the resulting set is stored as dstkey.
void	sync()
Integer	ttl(String key) The TTL command returns the remaining time to live in seconds of a key that has an EXPIRE set.
String	type(String key) Return the type of the value stored at key in form of a string.
String	unwatch()
String	watch(String key)
Integer	zadd(String key, double score, String member) Add the specified member having the specifeid score to the sorted set stored at key.
Integer	zcard(String key) Return the sorted set cardinality (number of elements).
Integer	zcount(String key, double min, double max)
Double	zincrby(String key, double score, String member) If member already exists in the sorted set adds the increment to its score and updates the position of the element in the sorted set accordingly.
Integer	zinterstore(String dstkey, String... sets) Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey.
Integer	zinterstore(String dstkey, ZParams params, String... sets) Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey.
Set<String>	zrange(String key, int start, int end)
Set<String>	zrangeByScore(String key, double min, double max) Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).
Set<String>	zrangeByScore(String key, double min, double max, int offset, int count) Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).
Set<Tuple>	zrangeByScoreWithScores(String key, double min, double max) Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).
Set<Tuple>	zrangeByScoreWithScores(String key, double min, double max, int offset, int count) Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).
Set<Tuple>	zrangeWithScores(String key, int start, int end)
Integer	zrank(String key, String member) Return the rank (or index) or member in the sorted set at key, with scores being ordered from low to high.
Integer	zrem(String key, String member) Remove the specified member from the sorted set value stored at key.
Integer	zremrangeByRank(String key, int start, int end) Remove all elements in the sorted set at key with rank between start and end.
Integer	zremrangeByScore(String key, double start, double end) Remove all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).
Set<String>	zrevrange(String key, int start, int end)
Set<Tuple>	zrevrangeWithScores(String key, int start, int end)
Integer	zrevrank(String key, String member) Return the rank (or index) or member in the sorted set at key, with scores being ordered from high to low.
Double	zscore(String key, String member) Return the score of the specified element of the sorted set at key.
Integer	zunionstore(String dstkey, String... sets) Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey.
Integer	zunionstore(String dstkey, ZParams params, String... sets) Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Jedis

public Jedis(String host)

Jedis

public Jedis(String host,
             int port)

Jedis

public Jedis(String host,
             int port,
             int timeout)

Jedis

public Jedis(JedisShardInfo shardInfo)

Method Detail

ping

public String ping()

set

public String set(String key,
                  String value)

Set the string value as value of the key. The string can't be longer than 1073741824 bytes (1 GB).

Time complexity: O(1)

Parameters:

key -

value -

Returns:

Status code reply

get

public String get(String key)

Get the value of the specified key. If the key does not exist the special value 'nil' is returned. If the value stored at key is not a string an error is returned because GET can only handle string values.

Time complexity: O(1)

Parameters:

key -

Returns:

Bulk reply

quit

public void quit()

Ask the server to silently close the connection.

exists

public Integer exists(String key)

Test if the specified key exists. The command returns "0" if the key exists, otherwise "1" is returned. Note that even keys set with an empty string as value will return "1". Time complexity: O(1)

Parameters:

key -

Returns:

Integer reply, "0" if the key exists, otherwise "1"

del

public Integer del(String... keys)

Remove the specified keys. If a given key does not exist no operation is performed for this key. The command returns the number of keys removed. Time complexity: O(1)

Parameters:

keys -

Returns:

Integer reply, specifically: an integer greater than 0 if one or more keys were removed 0 if none of the specified key existed

type

public String type(String key)

Return the type of the value stored at key in form of a string. The type can be one of "none", "string", "list", "set". "none" is returned if the key does not exist. Time complexity: O(1)

Parameters:

key -

Returns:

Status code reply, specifically: "none" if the key does not exist "string" if the key contains a String value "list" if the key contains a List value "set" if the key contains a Set value "zset" if the key contains a Sorted Set value "hash" if the key contains a Hash value

flushDB

public String flushDB()

Delete all the keys of the currently selected DB. This command never fails.

Returns:

Status code reply

keys

public List<String> keys(String pattern)

Returns all the keys matching the glob-style pattern as space separated strings. For example if you have in the database the keys "foo" and "foobar" the command "KEYS foo*" will return "foo foobar".

Note that while the time complexity for this operation is O(n) the constant times are pretty low. For example Redis running on an entry level laptop can scan a 1 million keys database in 40 milliseconds. Still it's better to consider this one of the slow commands that may ruin the DB performance if not used with care.

In other words this command is intended only for debugging and special operations like creating a script to change the DB schema. Don't use it in your normal code. Use Redis Sets in order to group together a subset of objects.

Glob style patterns examples:

• h?llo will match hello hallo hhllo
• h*llo will match hllo heeeello
• h[ae]llo will match hello and hallo, but not hillo

Use \ to escape special chars if you want to match them verbatim.

Time complexity: O(n) (with n being the number of keys in the DB, and assuming keys and pattern of limited length)

Parameters:

pattern -

Returns:

Multi bulk reply

randomKey

public String randomKey()

Return a randomly selected key from the currently selected DB.

Time complexity: O(1)

Returns:

Singe line reply, specifically the randomly selected key or an empty string is the database is empty

rename

public String rename(String oldkey,
                     String newkey)

Atomically renames the key oldkey to newkey. If the source and destination name are the same an error is returned. If newkey already exists it is overwritten.

Time complexity: O(1)

Parameters:

oldkey -

newkey -

Returns:

Status code repy

renamenx

public Integer renamenx(String oldkey,
                        String newkey)

Rename oldkey into newkey but fails if the destination key newkey already exists.

Time complexity: O(1)

Parameters:

oldkey -

newkey -

Returns:

Integer reply, specifically: 1 if the key was renamed 0 if the target key already exist

dbSize

public Integer dbSize()

Return the number of keys in the currently selected database.

Returns:

Integer reply

expire

public Integer expire(String key,
                      int seconds)

Set a timeout on the specified key. After the timeout the key will be automatically deleted by the server. A key with an associated timeout is said to be volatile in Redis terminology.

Voltile keys are stored on disk like the other keys, the timeout is persistent too like all the other aspects of the dataset. Saving a dataset containing expires and stopping the server does not stop the flow of time as Redis stores on disk the time when the key will no longer be available as Unix time, and not the remaining seconds.

Since Redis 2.1.3 you can update the value of the timeout of a key already having an expire set. It is also possible to undo the expire at all turning the key into a normal key using the PERSIST command.

Time complexity: O(1)

Parameters:

key -

seconds -

Returns:

Integer reply, specifically: 1: the timeout was set. 0: the timeout was not set since the key already has an associated timeout (this may happen only in Redis versions < 2.1.3, Redis >= 2.1.3 will happily update the timeout), or the key does not exist.

See Also:

ExpireCommand

expireAt

public Integer expireAt(String key,
                        long unixTime)

EXPIREAT works exctly like EXPIRE but instead to get the number of seconds representing the Time To Live of the key as a second argument (that is a relative way of specifing the TTL), it takes an absolute one in the form of a UNIX timestamp (Number of seconds elapsed since 1 Gen 1970).

EXPIREAT was introduced in order to implement the Append Only File persistence mode so that EXPIRE commands are automatically translated into EXPIREAT commands for the append only file. Of course EXPIREAT can also used by programmers that need a way to simply specify that a given key should expire at a given time in the future.

Since Redis 2.1.3 you can update the value of the timeout of a key already having an expire set. It is also possible to undo the expire at all turning the key into a normal key using the PERSIST command.

Time complexity: O(1)

Parameters:

key -

unixTime -

Returns:

Integer reply, specifically: 1: the timeout was set. 0: the timeout was not set since the key already has an associated timeout (this may happen only in Redis versions < 2.1.3, Redis >= 2.1.3 will happily update the timeout), or the key does not exist.

See Also:

ExpireCommand

ttl

public Integer ttl(String key)

The TTL command returns the remaining time to live in seconds of a key that has an EXPIRE set. This introspection capability allows a Redis client to check how many seconds a given key will continue to be part of the dataset.

Parameters:

key -

Returns:

Integer reply, returns the remaining time to live in seconds of a key that has an EXPIRE. If the Key does not exists or does not have an associated expire, -1 is returned.

select

public String select(int index)

Select the DB with having the specified zero-based numeric index. For default every new client connection is automatically selected to DB 0.

Parameters:

index -

Returns:

Status code reply

move

public Integer move(String key,
                    int dbIndex)

Move the specified key from the currently selected DB to the specified destination DB. Note that this command returns 1 only if the key was successfully moved, and 0 if the target key was already there or if the source key was not found at all, so it is possible to use MOVE as a locking primitive.

Parameters:

key -

dbIndex -

Returns:

Integer reply, specifically: 1 if the key was moved 0 if the key was not moved because already present on the target DB or was not found in the current DB.

flushAll

public String flushAll()

Delete all the keys of all the existing databases, not just the currently selected one. This command never fails.

Returns:

Status code reply

getSet

public String getSet(String key,
                     String value)

GETSET is an atomic set this value and return the old value command. Set key to the string value and return the old value stored at key. The string can't be longer than 1073741824 bytes (1 GB).

Time complexity: O(1)

Parameters:

key -

value -

Returns:

Bulk reply

mget

public List<String> mget(String... keys)

Get the values of all the specified keys. If one or more keys dont exist or is not of type String, a 'nil' value is returned instead of the value of the specified key, but the operation never fails.

Time complexity: O(1) for every key

Parameters:

keys -

Returns:

Multi bulk reply

setnx

public Integer setnx(String key,
                     String value)

SETNX works exactly like SET with the only difference that if the key already exists no operation is performed. SETNX actually means "SET if Not eXists".

Time complexity: O(1)

Parameters:

key -

value -

Returns:

Integer reply, specifically: 1 if the key was set 0 if the key was not set

setex

public String setex(String key,
                    int seconds,
                    String value)

The command is exactly equivalent to the following group of commands: SET + EXPIRE. The operation is atomic.

Time complexity: O(1)

Parameters:

key -

seconds -

value -

Returns:

Status code reply

mset

public String mset(String... keysvalues)

Set the the respective keys to the respective values. MSET will replace old values with new values, while MSETNX will not perform any operation at all even if just a single key already exists.

Because of this semantic MSETNX can be used in order to set different keys representing different fields of an unique logic object in a way that ensures that either all the fields or none at all are set.

Both MSET and MSETNX are atomic operations. This means that for instance if the keys A and B are modified, another client talking to Redis can either see the changes to both A and B at once, or no modification at all.

Parameters:

keysvalues -

Returns:

Status code reply Basically +OK as MSET can't fail

See Also:

msetnx(String...)

msetnx

public Integer msetnx(String... keysvalues)

Set the the respective keys to the respective values. MSET will replace old values with new values, while MSETNX will not perform any operation at all even if just a single key already exists.

Because of this semantic MSETNX can be used in order to set different keys representing different fields of an unique logic object in a way that ensures that either all the fields or none at all are set.

Both MSET and MSETNX are atomic operations. This means that for instance if the keys A and B are modified, another client talking to Redis can either see the changes to both A and B at once, or no modification at all.

Parameters:

keysvalues -

Returns:

Integer reply, specifically: 1 if the all the keys were set 0 if no key was set (at least one key already existed)

See Also:

mset(String...)

decrBy

public Integer decrBy(String key,
                      int integer)

IDECRBY work just like INCR but instead to decrement by 1 the decrement is integer.

INCR commands are limited to 64 bit signed integers.

Note: this is actually a string operation, that is, in Redis there are not "integer" types. Simply the string stored at the key is parsed as a base 10 64 bit signed integer, incremented, and then converted back as a string.

Time complexity: O(1)

Parameters:

key -

integer -

Returns:

Integer reply, this commands will reply with the new value of key after the increment.

See Also:

incr(String), decr(String), incrBy(String, int)

decr

public Integer decr(String key)

Decrement the number stored at key by one. If the key does not exist or contains a value of a wrong type, set the key to the value of "0" before to perform the decrement operation.

INCR commands are limited to 64 bit signed integers.

Note: this is actually a string operation, that is, in Redis there are not "integer" types. Simply the string stored at the key is parsed as a base 10 64 bit signed integer, incremented, and then converted back as a string.

Time complexity: O(1)

Parameters:

key -

Returns:

Integer reply, this commands will reply with the new value of key after the increment.

See Also:

incr(String), incrBy(String, int), decrBy(String, int)

incrBy

public Integer incrBy(String key,
                      int integer)

INCRBY work just like INCR but instead to increment by 1 the increment is integer.

INCR commands are limited to 64 bit signed integers.

Note: this is actually a string operation, that is, in Redis there are not "integer" types. Simply the string stored at the key is parsed as a base 10 64 bit signed integer, incremented, and then converted back as a string.

Time complexity: O(1)

Parameters:

key -

integer -

Returns:

Integer reply, this commands will reply with the new value of key after the increment.

See Also:

incr(String), decr(String), decrBy(String, int)

incr

public Integer incr(String key)

Increment the number stored at key by one. If the key does not exist or contains a value of a wrong type, set the key to the value of "0" before to perform the increment operation.

INCR commands are limited to 64 bit signed integers.

Note: this is actually a string operation, that is, in Redis there are not "integer" types. Simply the string stored at the key is parsed as a base 10 64 bit signed integer, incremented, and then converted back as a string.

Time complexity: O(1)

Parameters:

key -

Returns:

Integer reply, this commands will reply with the new value of key after the increment.

See Also:

incrBy(String, int), decr(String), decrBy(String, int)

append

public Integer append(String key,
                      String value)

If the key already exists and is a string, this command appends the provided value at the end of the string. If the key does not exist it is created and set as an empty string, so APPEND will be very similar to SET in this special case.

Time complexity: O(1). The amortized time complexity is O(1) assuming the appended value is small and the already present value is of any size, since the dynamic string library used by Redis will double the free space available on every reallocation.

Parameters:

key -

value -

Returns:

Integer reply, specifically the total length of the string after the append operation.

substr

public String substr(String key,
                     int start,
                     int end)

Return a subset of the string from offset start to offset end (both offsets are inclusive). Negative offsets can be used in order to provide an offset starting from the end of the string. So -1 means the last char, -2 the penultimate and so forth.

The function handles out of range requests without raising an error, but just limiting the resulting range to the actual length of the string.

Time complexity: O(start+n) (with start being the start index and n the total length of the requested range). Note that the lookup part of this command is O(1) so for small strings this is actually an O(1) command.

Parameters:

key -

start -

end -

Returns:

Bulk reply

hset

public Integer hset(String key,
                    String field,
                    String value)

Set the specified hash field to the specified value.

If key does not exist, a new key holding a hash is created.

Time complexity: O(1)

Parameters:

key -

field -

value -

Returns:

If the field already exists, and the HSET just produced an update of the value, 0 is returned, otherwise if a new field is created 1 is returned.

hget

public String hget(String key,
                   String field)

If key holds a hash, retrieve the value associated to the specified field.

If the field is not found or the key does not exist, a special 'nil' value is returned.

Time complexity: O(1)

Parameters:

key -

field -

Returns:

Bulk reply

hsetnx

public Integer hsetnx(String key,
                      String field,
                      String value)

Set the specified hash field to the specified value if the field not exists. Time complexity: O(1)

Parameters:

key -

field -

value -

Returns:

If the field already exists, 0 is returned, otherwise if a new field is created 1 is returned.

hmset

public String hmset(String key,
                    Map<String,String> hash)

Set the respective fields to the respective values. HMSET replaces old values with new values.

If key does not exist, a new key holding a hash is created.

Time complexity: O(N) (with N being the number of fields)

Parameters:

key -

hash -

Returns:

Always OK because HMSET can't fail

hmget

public List<String> hmget(String key,
                          String... fields)

Retrieve the values associated to the specified fields.

If some of the specified fields do not exist, nil values are returned. Non existing keys are considered like empty hashes.

Time complexity: O(N) (with N being the number of fields)

Parameters:

key -

fields -

Returns:

Multi Bulk Reply specifically a list of all the values associated with the specified fields, in the same order of the request.

hincrBy

public Integer hincrBy(String key,
                       String field,
                       int value)

Increment the number stored at field in the hash at key by value. If key does not exist, a new key holding a hash is created. If field does not exist or holds a string, the value is set to 0 before applying the operation. Since the value argument is signed you can use this command to perform both increments and decrements.

The range of values supported by HINCRBY is limited to 64 bit signed integers.

Time complexity: O(1)

Parameters:

key -

field -

value -

Returns:

Integer reply The new value at field after the increment operation.

hexists

public Integer hexists(String key,
                       String field)

Test for existence of a specified field in a hash. Time complexity: O(1)

Parameters:

key -

field -

Returns:

Return 1 if the hash stored at key contains the specified field. Return 0 if the key is not found or the field is not present.

hdel

public Integer hdel(String key,
                    String field)

Remove the specified field from an hash stored at key.

Time complexity: O(1)

Parameters:

key -

field -

Returns:

If the field was present in the hash it is deleted and 1 is returned, otherwise 0 is returned and no operation is performed.

hlen

public Integer hlen(String key)

Return the number of items in a hash.

Time complexity: O(1)

Parameters:

key -

Returns:

The number of entries (fields) contained in the hash stored at key. If the specified key does not exist, 0 is returned assuming an empty hash.

hkeys

public List<String> hkeys(String key)

Return all the fields in a hash.

Time complexity: O(N), where N is the total number of entries

Parameters:

key -

Returns:

All the fields names contained into a hash.

hvals

public List<String> hvals(String key)

Return all the values in a hash.

Time complexity: O(N), where N is the total number of entries

Parameters:

key -

Returns:

All the fields values contained into a hash.

hgetAll

public Map<String,String> hgetAll(String key)

Return all the fields and associated values in a hash.

Time complexity: O(N), where N is the total number of entries

Parameters:

key -

Returns:

All the fields and values contained into a hash.

rpush

public Integer rpush(String key,
                     String string)

Add the string value to the head (LPUSH) or tail (RPUSH) of the list stored at key. If the key does not exist an empty list is created just before the append operation. If the key exists but is not a List an error is returned.

Time complexity: O(1)

Parameters:

key -

string -

Returns:

Integer reply, specifically, the number of elements inside the list after the push operation.

See Also:

lpush(String, String)

lpush

public Integer lpush(String key,
                     String string)

Add the string value to the head (LPUSH) or tail (RPUSH) of the list stored at key. If the key does not exist an empty list is created just before the append operation. If the key exists but is not a List an error is returned.

Time complexity: O(1)

Parameters:

key -

string -

Returns:

Integer reply, specifically, the number of elements inside the list after the push operation.

See Also:

rpush(String, String)

llen

public Integer llen(String key)

Return the length of the list stored at the specified key. If the key does not exist zero is returned (the same behaviour as for empty lists). If the value stored at key is not a list an error is returned.

Time complexity: O(1)

Parameters:

key -

Returns:

The length of the list.

lrange

public List<String> lrange(String key,
                           int start,
                           int end)

Return the specified elements of the list stored at the specified key. Start and end are zero-based indexes. 0 is the first element of the list (the list head), 1 the next element and so on.

For example LRANGE foobar 0 2 will return the first three elements of the list.

start and end can also be negative numbers indicating offsets from the end of the list. For example -1 is the last element of the list, -2 the penultimate element and so on.

Consistency with range functions in various programming languages

Note that if you have a list of numbers from 0 to 100, LRANGE 0 10 will return 11 elements, that is, rightmost item is included. This may or may not be consistent with behavior of range-related functions in your programming language of choice (think Ruby's Range.new, Array#slice or Python's range() function).

LRANGE behavior is consistent with one of Tcl.

Out-of-range indexes

Indexes out of range will not produce an error: if start is over the end of the list, or start > end, an empty list is returned. If end is over the end of the list Redis will threat it just like the last element of the list.

Time complexity: O(start+n) (with n being the length of the range and start being the start offset)

Parameters:

key -

start -

end -

Returns:

Multi bulk reply, specifically a list of elements in the specified range.

ltrim

public String ltrim(String key,
                    int start,
                    int end)

Trim an existing list so that it will contain only the specified range of elements specified. Start and end are zero-based indexes. 0 is the first element of the list (the list head), 1 the next element and so on.

For example LTRIM foobar 0 2 will modify the list stored at foobar key so that only the first three elements of the list will remain.

start and end can also be negative numbers indicating offsets from the end of the list. For example -1 is the last element of the list, -2 the penultimate element and so on.

Indexes out of range will not produce an error: if start is over the end of the list, or start > end, an empty list is left as value. If end over the end of the list Redis will threat it just like the last element of the list.

Hint: the obvious use of LTRIM is together with LPUSH/RPUSH. For example:

lpush("mylist", "someelement"); ltrim("mylist", 0, 99); *

The above two commands will push elements in the list taking care that the list will not grow without limits. This is very useful when using Redis to store logs for example. It is important to note that when used in this way LTRIM is an O(1) operation because in the average case just one element is removed from the tail of the list.

Time complexity: O(n) (with n being len of list - len of range)

Parameters:

key -

start -

end -

Returns:

Status code reply

lindex

public String lindex(String key,
                     int index)

Return the specified element of the list stored at the specified key. 0 is the first element, 1 the second and so on. Negative indexes are supported, for example -1 is the last element, -2 the penultimate and so on.

If the value stored at key is not of list type an error is returned. If the index is out of range a 'nil' reply is returned.

Note that even if the average time complexity is O(n) asking for the first or the last element of the list is O(1).

Time complexity: O(n) (with n being the length of the list)

Parameters:

key -

index -

Returns:

Bulk reply, specifically the requested element

lset

public String lset(String key,
                   int index,
                   String value)

Set a new value as the element at index position of the List at key.

Out of range indexes will generate an error.

Similarly to other list commands accepting indexes, the index can be negative to access elements starting from the end of the list. So -1 is the last element, -2 is the penultimate, and so forth.

Time complexity:

O(N) (with N being the length of the list), setting the first or last elements of the list is O(1).

Parameters:

key -

index -

value -

Returns:

Status code reply

See Also:

lindex(String, int)

lrem

public Integer lrem(String key,
                    int count,
                    String value)

Remove the first count occurrences of the value element from the list. If count is zero all the elements are removed. If count is negative elements are removed from tail to head, instead to go from head to tail that is the normal behaviour. So for example LREM with count -2 and hello as value to remove against the list (a,b,c,hello,x,hello,hello) will lave the list (a,b,c,hello,x). The number of removed elements is returned as an integer, see below for more information about the returned value. Note that non existing keys are considered like empty lists by LREM, so LREM against non existing keys will always return 0.

Time complexity: O(N) (with N being the length of the list)

Parameters:

key -

count -

value -

Returns:

Integer Reply, specifically: The number of removed elements if the operation succeeded

lpop

public String lpop(String key)

Atomically return and remove the first (LPOP) or last (RPOP) element of the list. For example if the list contains the elements "a","b","c" LPOP will return "a" and the list will become "b","c".

If the key does not exist or the list is already empty the special value 'nil' is returned.

Parameters:

key -

Returns:

Bulk reply

See Also:

rpop(String)

rpop

public String rpop(String key)

Atomically return and remove the first (LPOP) or last (RPOP) element of the list. For example if the list contains the elements "a","b","c" LPOP will return "a" and the list will become "b","c".

If the key does not exist or the list is already empty the special value 'nil' is returned.

Parameters:

key -

Returns:

Bulk reply

See Also:

lpop(String)

rpoplpush

public String rpoplpush(String srckey,
                        String dstkey)

Atomically return and remove the last (tail) element of the srckey list, and push the element as the first (head) element of the dstkey list. For example if the source list contains the elements "a","b","c" and the destination list contains the elements "foo","bar" after an RPOPLPUSH command the content of the two lists will be "a","b" and "c","foo","bar".

If the key does not exist or the list is already empty the special value 'nil' is returned. If the srckey and dstkey are the same the operation is equivalent to removing the last element from the list and pusing it as first element of the list, so it's a "list rotation" command.

Time complexity: O(1)

Parameters:

srckey -

dstkey -

Returns:

Bulk reply

sadd

public Integer sadd(String key,
                    String member)

Add the specified member to the set value stored at key. If member is already a member of the set no operation is performed. If key does not exist a new set with the specified member as sole member is created. If the key exists but does not hold a set value an error is returned.

Time complexity O(1)

Parameters:

key -

member -

Returns:

Integer reply, specifically: 1 if the new element was added 0 if the element was already a member of the set

smembers

public Set<String> smembers(String key)

Return all the members (elements) of the set value stored at key. This is just syntax glue for SINTER.

Time complexity O(N)

Parameters:

key -

Returns:

Multi bulk reply

srem

public Integer srem(String key,
                    String member)

Remove the specified member from the set value stored at key. If member was not a member of the set no operation is performed. If key does not hold a set value an error is returned.

Time complexity O(1)

Parameters:

key -

member -

Returns:

Integer reply, specifically: 1 if the new element was removed 0 if the new element was not a member of the set

spop

public String spop(String key)

Remove a random element from a Set returning it as return value. If the Set is empty or the key does not exist, a nil object is returned.

The srandmember(String) command does a similar work but the returned element is not removed from the Set.

Time complexity O(1)

Parameters:

key -

Returns:

Bulk reply

smove

public Integer smove(String srckey,
                     String dstkey,
                     String member)

Move the specifided member from the set at srckey to the set at dstkey. This operation is atomic, in every given moment the element will appear to be in the source or destination set for accessing clients.

If the source set does not exist or does not contain the specified element no operation is performed and zero is returned, otherwise the element is removed from the source set and added to the destination set. On success one is returned, even if the element was already present in the destination set.

An error is raised if the source or destination keys contain a non Set value.

Time complexity O(1)

Parameters:

srckey -

dstkey -

member -

Returns:

Integer reply, specifically: 1 if the element was moved 0 if the element was not found on the first set and no operation was performed

scard

public Integer scard(String key)

Return the set cardinality (number of elements). If the key does not exist 0 is returned, like for empty sets.

Parameters:

key -

Returns:

Integer reply, specifically: the cardinality (number of elements) of the set as an integer.

sismember

public Integer sismember(String key,
                         String member)

Return 1 if member is a member of the set stored at key, otherwise 0 is returned.

Time complexity O(1)

Parameters:

key -

member -

Returns:

Integer reply, specifically: 1 if the element is a member of the set 0 if the element is not a member of the set OR if the key does not exist

sinter

public Set<String> sinter(String... keys)

Return the members of a set resulting from the intersection of all the sets hold at the specified keys. Like in LRANGE the result is sent to the client as a multi-bulk reply (see the protocol specification for more information). If just a single key is specified, then this command produces the same result as SMEMBERS. Actually SMEMBERS is just syntax sugar for SINTER.

Non existing keys are considered like empty sets, so if one of the keys is missing an empty set is returned (since the intersection with an empty set always is an empty set).

Time complexity O(N*M) worst case where N is the cardinality of the smallest set and M the number of sets

Parameters:

keys -

Returns:

Multi bulk reply, specifically the list of common elements.

sinterstore

public Integer sinterstore(String dstkey,
                           String... keys)

This commnad works exactly like SINTER but instead of being returned the resulting set is sotred as dstkey.

Time complexity O(N*M) worst case where N is the cardinality of the smallest set and M the number of sets

Parameters:

dstkey -

keys -

Returns:

Status code reply

sunion

public Set<String> sunion(String... keys)

Return the members of a set resulting from the union of all the sets hold at the specified keys. Like in LRANGE the result is sent to the client as a multi-bulk reply (see the protocol specification for more information). If just a single key is specified, then this command produces the same result as SMEMBERS.

Non existing keys are considered like empty sets.

Time complexity O(N) where N is the total number of elements in all the provided sets

Parameters:

keys -

Returns:

Multi bulk reply, specifically the list of common elements.

sunionstore

public Integer sunionstore(String dstkey,
                           String... keys)

This command works exactly like SUNION but instead of being returned the resulting set is stored as dstkey. Any existing value in dstkey will be over-written.

Time complexity O(N) where N is the total number of elements in all the provided sets

Parameters:

dstkey -

keys -

Returns:

Status code reply

sdiff

public Set<String> sdiff(String... keys)

Return the difference between the Set stored at key1 and all the Sets key2, ..., keyN

Example:

 key1 = [x, a, b, c]
 key2 = [c]
 key3 = [a, d]
 SDIFF key1,key2,key3 => [x, b]
 

Non existing keys are considered like empty sets.

Time complexity:

O(N) with N being the total number of elements of all the sets

Parameters:

keys -

Returns:

Return the members of a set resulting from the difference between the first set provided and all the successive sets.

sdiffstore

public Integer sdiffstore(String dstkey,
                          String... keys)

This command works exactly like SDIFF but instead of being returned the resulting set is stored in dstkey.

Parameters:

dstkey -

keys -

Returns:

Status code reply

srandmember

public String srandmember(String key)

Return a random element from a Set, without removing the element. If the Set is empty or the key does not exist, a nil object is returned.

The SPOP command does a similar work but the returned element is popped (removed) from the Set.

Time complexity O(1)

Parameters:

key -

Returns:

Bulk reply

zadd

public Integer zadd(String key,
                    double score,
                    String member)

Add the specified member having the specifeid score to the sorted set stored at key. If member is already a member of the sorted set the score is updated, and the element reinserted in the right position to ensure sorting. If key does not exist a new sorted set with the specified member as sole member is crated. If the key exists but does not hold a sorted set value an error is returned.

The score value can be the string representation of a double precision floating point number.

Time complexity O(log(N)) with N being the number of elements in the sorted set

Parameters:

key -

score -

member -

Returns:

Integer reply, specifically: 1 if the new element was added 0 if the element was already a member of the sorted set and the score was updated

zrange

public Set<String> zrange(String key,
                          int start,
                          int end)

zrem

public Integer zrem(String key,
                    String member)

Remove the specified member from the sorted set value stored at key. If member was not a member of the set no operation is performed. If key does not not hold a set value an error is returned.

Time complexity O(log(N)) with N being the number of elements in the sorted set

Parameters:

key -

member -

Returns:

Integer reply, specifically: 1 if the new element was removed 0 if the new element was not a member of the set

zincrby

public Double zincrby(String key,
                      double score,
                      String member)

If member already exists in the sorted set adds the increment to its score and updates the position of the element in the sorted set accordingly. If member does not already exist in the sorted set it is added with increment as score (that is, like if the previous score was virtually zero). If key does not exist a new sorted set with the specified member as sole member is crated. If the key exists but does not hold a sorted set value an error is returned.

The score value can be the string representation of a double precision floating point number. It's possible to provide a negative value to perform a decrement.

For an introduction to sorted sets check the Introduction to Redis data types page.

Time complexity O(log(N)) with N being the number of elements in the sorted set

Parameters:

key -

score -

member -

Returns:

The new score

zrank

public Integer zrank(String key,
                     String member)

Return the rank (or index) or member in the sorted set at key, with scores being ordered from low to high.

When the given member does not exist in the sorted set, the special value 'nil' is returned. The returned rank (or index) of the member is 0-based for both commands.

Time complexity:

O(log(N))

Parameters:

key -

member -

Returns:

Integer reply or a nil bulk reply, specifically: the rank of the element as an integer reply if the element exists. A nil bulk reply if there is no such element.

See Also:

zrevrank(String, String)

zrevrank

public Integer zrevrank(String key,
                        String member)

Return the rank (or index) or member in the sorted set at key, with scores being ordered from high to low.

When the given member does not exist in the sorted set, the special value 'nil' is returned. The returned rank (or index) of the member is 0-based for both commands.

Time complexity:

O(log(N))

Parameters:

key -

member -

Returns:

Integer reply or a nil bulk reply, specifically: the rank of the element as an integer reply if the element exists. A nil bulk reply if there is no such element.

See Also:

zrank(String, String)

zrevrange

public Set<String> zrevrange(String key,
                             int start,
                             int end)

zrangeWithScores

public Set<Tuple> zrangeWithScores(String key,
                                   int start,
                                   int end)

zrevrangeWithScores

public Set<Tuple> zrevrangeWithScores(String key,
                                      int start,
                                      int end)

zcard

public Integer zcard(String key)

Return the sorted set cardinality (number of elements). If the key does not exist 0 is returned, like for empty sorted sets.

Time complexity O(1)

Parameters:

key -

Returns:

the cardinality (number of elements) of the set as an integer.

zscore

public Double zscore(String key,
                     String member)

Return the score of the specified element of the sorted set at key. If the specified element does not exist in the sorted set, or the key does not exist at all, a special 'nil' value is returned.

Time complexity: O(1)

Parameters:

key -

member -

Returns:

the score

multi

public Transaction multi()

multi

public List<Object> multi(TransactionBlock jedisTransaction)

connect

public void connect()
             throws UnknownHostException,
                    IOException

Throws:

UnknownHostException

IOException

disconnect

public void disconnect()
                throws IOException

Throws:

IOException

watch

public String watch(String key)

unwatch

public String unwatch()

sort

public List<String> sort(String key)

Sort a Set or a List.

Sort the elements contained in the List, Set, or Sorted Set value at key. By default sorting is numeric with elements being compared as double precision floating point numbers. This is the simplest form of SORT.

Parameters:

key -

Returns:

Assuming the Set/List at key contains a list of numbers, the return value will be the list of numbers ordered from the smallest to the biggest number.

See Also:

sort(String, String), sort(String, SortingParams), sort(String, SortingParams, String)

sort

public List<String> sort(String key,
                         SortingParams sortingParameters)

Sort a Set or a List accordingly to the specified parameters.

examples:

Given are the following sets and key/values:

 x = [1, 2, 3]
 y = [a, b, c]
 
 k1 = z
 k2 = y
 k3 = x
 
 w1 = 9
 w2 = 8
 w3 = 7
 

Sort Order:

 sort(x) or sort(x, sp.asc())
 -> [1, 2, 3]
 
 sort(x, sp.desc())
 -> [3, 2, 1]
 
 sort(y)
 -> [c, a, b]
 
 sort(y, sp.alpha())
 -> [a, b, c]
 
 sort(y, sp.alpha().desc())
 -> [c, a, b]
 

Limit (e.g. for Pagination):

 sort(x, sp.limit(0, 2))
 -> [1, 2]
 
 sort(y, sp.alpha().desc().limit(1, 2))
 -> [b, a]
 

Sorting by external keys:

 sort(x, sb.by(w*))
 -> [3, 2, 1]
 
 sort(x, sb.by(w*).desc())
 -> [1, 2, 3]
 

Getting external keys:

 sort(x, sp.by(w*).get(k*))
 -> [x, y, z]
 
 sort(x, sp.by(w*).get(#).get(k*))
 -> [3, x, 2, y, 1, z]
 

Parameters:

key -

sortingParameters -

Returns:

a list of sorted elements.

See Also:

sort(String), sort(String, SortingParams, String)

blpop

public List<String> blpop(int timeout,
                          String... keys)

BLPOP (and BRPOP) is a blocking list pop primitive. You can see this commands as blocking versions of LPOP and RPOP able to block if the specified keys don't exist or contain empty lists.

The following is a description of the exact semantic. We describe BLPOP but the two commands are identical, the only difference is that BLPOP pops the element from the left (head) of the list, and BRPOP pops from the right (tail).

Non blocking behavior

When BLPOP is called, if at least one of the specified keys contain a non empty list, an element is popped from the head of the list and returned to the caller together with the name of the key (BLPOP returns a two elements array, the first element is the key, the second the popped value).

Keys are scanned from left to right, so for instance if you issue BLPOP list1 list2 list3 0 against a dataset where list1 does not exist but list2 and list3 contain non empty lists, BLPOP guarantees to return an element from the list stored at list2 (since it is the first non empty list starting from the left).

Blocking behavior

If none of the specified keys exist or contain non empty lists, BLPOP blocks until some other client performs a LPUSH or an RPUSH operation against one of the lists.

Once new data is present on one of the lists, the client finally returns with the name of the key unblocking it and the popped value.

When blocking, if a non-zero timeout is specified, the client will unblock returning a nil special value if the specified amount of seconds passed without a push operation against at least one of the specified keys.

The timeout argument is interpreted as an integer value. A timeout of zero means instead to block forever.

Multiple clients blocking for the same keys

Multiple clients can block for the same key. They are put into a queue, so the first to be served will be the one that started to wait earlier, in a first-blpopping first-served fashion.

blocking POP inside a MULTI/EXEC transaction

BLPOP and BRPOP can be used with pipelining (sending multiple commands and reading the replies in batch), but it does not make sense to use BLPOP or BRPOP inside a MULTI/EXEC block (a Redis transaction).

The behavior of BLPOP inside MULTI/EXEC when the list is empty is to return a multi-bulk nil reply, exactly what happens when the timeout is reached. If you like science fiction, think at it like if inside MULTI/EXEC the time will flow at infinite speed :)

Time complexity: O(1)

Parameters:

timeout -

keys -

Returns:

BLPOP returns a two-elements array via a multi bulk reply in order to return both the unblocking key and the popped value.

When a non-zero timeout is specified, and the BLPOP operation timed out, the return value is a nil multi bulk reply. Most client values will return false or nil accordingly to the programming language used.

See Also:

brpop(int, String...)

sort

public Integer sort(String key,
                    SortingParams sortingParameters,
                    String dstkey)

Sort a Set or a List accordingly to the specified parameters and store the result at dstkey.

Parameters:

key -

sortingParameters -

dstkey -

Returns:

The number of elements of the list at dstkey.

See Also:

sort(String, SortingParams), sort(String), sort(String, String)

sort

public Integer sort(String key,
                    String dstkey)

Sort a Set or a List and Store the Result at dstkey.

Sort the elements contained in the List, Set, or Sorted Set value at key and store the result at dstkey. By default sorting is numeric with elements being compared as double precision floating point numbers. This is the simplest form of SORT.

Parameters:

key -

dstkey -

Returns:

The number of elements of the list at dstkey.

See Also:

sort(String), sort(String, SortingParams), sort(String, SortingParams, String)

brpop

public List<String> brpop(int timeout,
                          String... keys)

BLPOP (and BRPOP) is a blocking list pop primitive. You can see this commands as blocking versions of LPOP and RPOP able to block if the specified keys don't exist or contain empty lists.

The following is a description of the exact semantic. We describe BLPOP but the two commands are identical, the only difference is that BLPOP pops the element from the left (head) of the list, and BRPOP pops from the right (tail).

Non blocking behavior

When BLPOP is called, if at least one of the specified keys contain a non empty list, an element is popped from the head of the list and returned to the caller together with the name of the key (BLPOP returns a two elements array, the first element is the key, the second the popped value).

Keys are scanned from left to right, so for instance if you issue BLPOP list1 list2 list3 0 against a dataset where list1 does not exist but list2 and list3 contain non empty lists, BLPOP guarantees to return an element from the list stored at list2 (since it is the first non empty list starting from the left).

Blocking behavior

If none of the specified keys exist or contain non empty lists, BLPOP blocks until some other client performs a LPUSH or an RPUSH operation against one of the lists.

Once new data is present on one of the lists, the client finally returns with the name of the key unblocking it and the popped value.

When blocking, if a non-zero timeout is specified, the client will unblock returning a nil special value if the specified amount of seconds passed without a push operation against at least one of the specified keys.

The timeout argument is interpreted as an integer value. A timeout of zero means instead to block forever.

Multiple clients blocking for the same keys

Multiple clients can block for the same key. They are put into a queue, so the first to be served will be the one that started to wait earlier, in a first-blpopping first-served fashion.

blocking POP inside a MULTI/EXEC transaction

BLPOP and BRPOP can be used with pipelining (sending multiple commands and reading the replies in batch), but it does not make sense to use BLPOP or BRPOP inside a MULTI/EXEC block (a Redis transaction).

The behavior of BLPOP inside MULTI/EXEC when the list is empty is to return a multi-bulk nil reply, exactly what happens when the timeout is reached. If you like science fiction, think at it like if inside MULTI/EXEC the time will flow at infinite speed :)

Time complexity: O(1)

Parameters:

timeout -

keys -

Returns:

BLPOP returns a two-elements array via a multi bulk reply in order to return both the unblocking key and the popped value.

When a non-zero timeout is specified, and the BLPOP operation timed out, the return value is a nil multi bulk reply. Most client values will return false or nil accordingly to the programming language used.

See Also:

blpop(int, String...)

auth

public String auth(String password)

Request for authentication in a password protected Redis server. A Redis server can be instructed to require a password before to allow clients to issue commands. This is done using the requirepass directive in the Redis configuration file. If the password given by the client is correct the server replies with an OK status code reply and starts accepting commands from the client. Otherwise an error is returned and the clients needs to try a new password. Note that for the high performance nature of Redis it is possible to try a lot of passwords in parallel in very short time, so make sure to generate a strong and very long password so that this attack is infeasible.

Parameters:

password -

Returns:

Status code reply

pipelined

public List<Object> pipelined(JedisPipeline jedisPipeline)

subscribe

public void subscribe(JedisPubSub jedisPubSub,
                      String... channels)

publish

public Integer publish(String channel,
                       String message)

psubscribe

public void psubscribe(JedisPubSub jedisPubSub,
                       String... patterns)

zcount

public Integer zcount(String key,
                      double min,
                      double max)

zrangeByScore

public Set<String> zrangeByScore(String key,
                                 double min,
                                 double max)

Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).

The elements having the same score are returned sorted lexicographically as ASCII strings (this follows from a property of Redis sorted sets and does not involve further computation).

Using the optional LIMIT it's possible to get only a range of the matching elements in an SQL-alike way. Note that if offset is large the commands needs to traverse the list for offset elements and this adds up to the O(M) figure.

The ZCOUNT command is similar to ZRANGEBYSCORE but instead of returning the actual elements in the specified interval, it just returns the number of matching elements.

Exclusive intervals and infinity

min and max can be -inf and +inf, so that you are not required to know what's the greatest or smallest element in order to take, for instance, elements "up to a given value".

Also while the interval is for default closed (inclusive) it's possible to specify open intervals prefixing the score with a "(" character, so for instance:

ZRANGEBYSCORE zset (1.3 5

Will return all the values with score > 1.3 and <= 5, while for instance:

ZRANGEBYSCORE zset (5 (10

Will return all the values with score > 5 and < 10 (5 and 10 excluded).

Time complexity:

O(log(N))+O(M) with N being the number of elements in the sorted set and M the number of elements returned by the command, so if M is constant (for instance you always ask for the first ten elements with LIMIT) you can consider it O(log(N))

Parameters:

key -

min -

max -

Returns:

Multi bulk reply specifically a list of elements in the specified score range.

See Also:

zrangeByScore(String, double, double), zrangeByScore(String, double, double, int, int), zrangeByScoreWithScores(String, double, double), zrangeByScoreWithScores(String, double, double, int, int), zcount(String, double, double)

zrangeByScore

public Set<String> zrangeByScore(String key,
                                 double min,
                                 double max,
                                 int offset,
                                 int count)

Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).

The elements having the same score are returned sorted lexicographically as ASCII strings (this follows from a property of Redis sorted sets and does not involve further computation).

Using the optional LIMIT it's possible to get only a range of the matching elements in an SQL-alike way. Note that if offset is large the commands needs to traverse the list for offset elements and this adds up to the O(M) figure.

The ZCOUNT command is similar to ZRANGEBYSCORE but instead of returning the actual elements in the specified interval, it just returns the number of matching elements.

Exclusive intervals and infinity

min and max can be -inf and +inf, so that you are not required to know what's the greatest or smallest element in order to take, for instance, elements "up to a given value".

Also while the interval is for default closed (inclusive) it's possible to specify open intervals prefixing the score with a "(" character, so for instance:

ZRANGEBYSCORE zset (1.3 5

Will return all the values with score > 1.3 and <= 5, while for instance:

ZRANGEBYSCORE zset (5 (10

Will return all the values with score > 5 and < 10 (5 and 10 excluded).

Time complexity:

O(log(N))+O(M) with N being the number of elements in the sorted set and M the number of elements returned by the command, so if M is constant (for instance you always ask for the first ten elements with LIMIT) you can consider it O(log(N))

Parameters:

key -

min -

max -

Returns:

Multi bulk reply specifically a list of elements in the specified score range.

See Also:

zrangeByScore(String, double, double), zrangeByScore(String, double, double, int, int), zrangeByScoreWithScores(String, double, double), zrangeByScoreWithScores(String, double, double, int, int), zcount(String, double, double)

zrangeByScoreWithScores

public Set<Tuple> zrangeByScoreWithScores(String key,
                                          double min,
                                          double max)

Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).

The elements having the same score are returned sorted lexicographically as ASCII strings (this follows from a property of Redis sorted sets and does not involve further computation).

Using the optional LIMIT it's possible to get only a range of the matching elements in an SQL-alike way. Note that if offset is large the commands needs to traverse the list for offset elements and this adds up to the O(M) figure.

The ZCOUNT command is similar to ZRANGEBYSCORE but instead of returning the actual elements in the specified interval, it just returns the number of matching elements.

Exclusive intervals and infinity

min and max can be -inf and +inf, so that you are not required to know what's the greatest or smallest element in order to take, for instance, elements "up to a given value".

Also while the interval is for default closed (inclusive) it's possible to specify open intervals prefixing the score with a "(" character, so for instance:

ZRANGEBYSCORE zset (1.3 5

Will return all the values with score > 1.3 and <= 5, while for instance:

ZRANGEBYSCORE zset (5 (10

Will return all the values with score > 5 and < 10 (5 and 10 excluded).

Time complexity:

O(log(N))+O(M) with N being the number of elements in the sorted set and M the number of elements returned by the command, so if M is constant (for instance you always ask for the first ten elements with LIMIT) you can consider it O(log(N))

Parameters:

key -

min -

max -

Returns:

Multi bulk reply specifically a list of elements in the specified score range.

See Also:

zrangeByScore(String, double, double), zrangeByScore(String, double, double, int, int), zrangeByScoreWithScores(String, double, double), zrangeByScoreWithScores(String, double, double, int, int), zcount(String, double, double)

zrangeByScoreWithScores

public Set<Tuple> zrangeByScoreWithScores(String key,
                                          double min,
                                          double max,
                                          int offset,
                                          int count)

Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).

The elements having the same score are returned sorted lexicographically as ASCII strings (this follows from a property of Redis sorted sets and does not involve further computation).

Using the optional LIMIT it's possible to get only a range of the matching elements in an SQL-alike way. Note that if offset is large the commands needs to traverse the list for offset elements and this adds up to the O(M) figure.

The ZCOUNT command is similar to ZRANGEBYSCORE but instead of returning the actual elements in the specified interval, it just returns the number of matching elements.

Exclusive intervals and infinity

min and max can be -inf and +inf, so that you are not required to know what's the greatest or smallest element in order to take, for instance, elements "up to a given value".

Also while the interval is for default closed (inclusive) it's possible to specify open intervals prefixing the score with a "(" character, so for instance:

ZRANGEBYSCORE zset (1.3 5

Will return all the values with score > 1.3 and <= 5, while for instance:

ZRANGEBYSCORE zset (5 (10

Will return all the values with score > 5 and < 10 (5 and 10 excluded).

Time complexity:

O(log(N))+O(M) with N being the number of elements in the sorted set and M the number of elements returned by the command, so if M is constant (for instance you always ask for the first ten elements with LIMIT) you can consider it O(log(N))

Parameters:

key -

min -

max -

Returns:

Multi bulk reply specifically a list of elements in the specified score range.

See Also:

zrangeByScore(String, double, double), zrangeByScore(String, double, double, int, int), zrangeByScoreWithScores(String, double, double), zrangeByScoreWithScores(String, double, double, int, int), zcount(String, double, double)

zremrangeByRank

public Integer zremrangeByRank(String key,
                               int start,
                               int end)

Remove all elements in the sorted set at key with rank between start and end. Start and end are 0-based with rank 0 being the element with the lowest score. Both start and end can be negative numbers, where they indicate offsets starting at the element with the highest rank. For example: -1 is the element with the highest score, -2 the element with the second highest score and so forth.

Time complexity: O(log(N))+O(M) with N being the number of elements in the sorted set and M the number of elements removed by the operation

zremrangeByScore

public Integer zremrangeByScore(String key,
                                double start,
                                double end)

Remove all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max).

Time complexity:

O(log(N))+O(M) with N being the number of elements in the sorted set and M the number of elements removed by the operation

Parameters:

key -

start -

end -

Returns:

Integer reply, specifically the number of elements removed.

zunionstore

public Integer zunionstore(String dstkey,
                           String... sets)

Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey. It is mandatory to provide the number of input keys N, before passing the input keys and the other (optional) arguments.

As the terms imply, the ZINTERSTORE command requires an element to be present in each of the given inputs to be inserted in the result. The ZUNIONSTORE command inserts all elements across all inputs.

Using the WEIGHTS option, it is possible to add weight to each input sorted set. This means that the score of each element in the sorted set is first multiplied by this weight before being passed to the aggregation. When this option is not given, all weights default to 1.

With the AGGREGATE option, it's possible to specify how the results of the union or intersection are aggregated. This option defaults to SUM, where the score of an element is summed across the inputs where it exists. When this option is set to be either MIN or MAX, the resulting set will contain the minimum or maximum score of an element across the inputs where it exists.

Time complexity: O(N) + O(M log(M)) with N being the sum of the sizes of the input sorted sets, and M being the number of elements in the resulting sorted set

Parameters:

dstkey -

sets -

Returns:

Integer reply, specifically the number of elements in the sorted set at dstkey

See Also:

zunionstore(String, String...), zunionstore(String, ZParams, String...), zinterstore(String, String...), zinterstore(String, ZParams, String...)

zunionstore

public Integer zunionstore(String dstkey,
                           ZParams params,
                           String... sets)

Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey. It is mandatory to provide the number of input keys N, before passing the input keys and the other (optional) arguments.

As the terms imply, the ZINTERSTORE command requires an element to be present in each of the given inputs to be inserted in the result. The ZUNIONSTORE command inserts all elements across all inputs.

Using the WEIGHTS option, it is possible to add weight to each input sorted set. This means that the score of each element in the sorted set is first multiplied by this weight before being passed to the aggregation. When this option is not given, all weights default to 1.

With the AGGREGATE option, it's possible to specify how the results of the union or intersection are aggregated. This option defaults to SUM, where the score of an element is summed across the inputs where it exists. When this option is set to be either MIN or MAX, the resulting set will contain the minimum or maximum score of an element across the inputs where it exists.

Time complexity: O(N) + O(M log(M)) with N being the sum of the sizes of the input sorted sets, and M being the number of elements in the resulting sorted set

Parameters:

dstkey -

sets -

params -

Returns:

Integer reply, specifically the number of elements in the sorted set at dstkey

See Also:

zunionstore(String, String...), zunionstore(String, ZParams, String...), zinterstore(String, String...), zinterstore(String, ZParams, String...)

zinterstore

public Integer zinterstore(String dstkey,
                           String... sets)

Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey. It is mandatory to provide the number of input keys N, before passing the input keys and the other (optional) arguments.

As the terms imply, the ZINTERSTORE command requires an element to be present in each of the given inputs to be inserted in the result. The ZUNIONSTORE command inserts all elements across all inputs.

Using the WEIGHTS option, it is possible to add weight to each input sorted set. This means that the score of each element in the sorted set is first multiplied by this weight before being passed to the aggregation. When this option is not given, all weights default to 1.

With the AGGREGATE option, it's possible to specify how the results of the union or intersection are aggregated. This option defaults to SUM, where the score of an element is summed across the inputs where it exists. When this option is set to be either MIN or MAX, the resulting set will contain the minimum or maximum score of an element across the inputs where it exists.

Time complexity: O(N) + O(M log(M)) with N being the sum of the sizes of the input sorted sets, and M being the number of elements in the resulting sorted set

Parameters:

dstkey -

sets -

Returns:

Integer reply, specifically the number of elements in the sorted set at dstkey

See Also:

zunionstore(String, String...), zunionstore(String, ZParams, String...), zinterstore(String, String...), zinterstore(String, ZParams, String...)

zinterstore

public Integer zinterstore(String dstkey,
                           ZParams params,
                           String... sets)

Creates a union or intersection of N sorted sets given by keys k1 through kN, and stores it at dstkey. It is mandatory to provide the number of input keys N, before passing the input keys and the other (optional) arguments.

As the terms imply, the ZINTERSTORE command requires an element to be present in each of the given inputs to be inserted in the result. The ZUNIONSTORE command inserts all elements across all inputs.

Using the WEIGHTS option, it is possible to add weight to each input sorted set. This means that the score of each element in the sorted set is first multiplied by this weight before being passed to the aggregation. When this option is not given, all weights default to 1.

With the AGGREGATE option, it's possible to specify how the results of the union or intersection are aggregated. This option defaults to SUM, where the score of an element is summed across the inputs where it exists. When this option is set to be either MIN or MAX, the resulting set will contain the minimum or maximum score of an element across the inputs where it exists.

Time complexity: O(N) + O(M log(M)) with N being the sum of the sizes of the input sorted sets, and M being the number of elements in the resulting sorted set

Parameters:

dstkey -

sets -

params -

Returns:

Integer reply, specifically the number of elements in the sorted set at dstkey

See Also:

zunionstore(String, String...), zunionstore(String, ZParams, String...), zinterstore(String, String...), zinterstore(String, ZParams, String...)

save

public String save()

Synchronously save the DB on disk.

Save the whole dataset on disk (this means that all the databases are saved, as well as keys with an EXPIRE set (the expire is preserved). The server hangs while the saving is not completed, no connection is served in the meanwhile. An OK code is returned when the DB was fully stored in disk.

The background variant of this command is BGSAVE that is able to perform the saving in the background while the server continues serving other clients.

Returns:

Status code reply

bgsave

public String bgsave()

Asynchronously save the DB on disk.

Save the DB in background. The OK code is immediately returned. Redis forks, the parent continues to server the clients, the child saves the DB on disk then exit. A client my be able to check if the operation succeeded using the LASTSAVE command.

Returns:

Status code reply

bgrewriteaof

public String bgrewriteaof()

Rewrite the append only file in background when it gets too big. Please for detailed information about the Redis Append Only File check the Append Only File Howto.

BGREWRITEAOF rewrites the Append Only File in background when it gets too big. The Redis Append Only File is a Journal, so every operation modifying the dataset is logged in the Append Only File (and replayed at startup). This means that the Append Only File always grows. In order to rebuild its content the BGREWRITEAOF creates a new version of the append only file starting directly form the dataset in memory in order to guarantee the generation of the minimal number of commands needed to rebuild the database.

Returns:

Status code reply

lastsave

public Integer lastsave()

Return the UNIX time stamp of the last successfully saving of the dataset on disk.

Return the UNIX TIME of the last DB save executed with success. A client may check if a BGSAVE command succeeded reading the LASTSAVE value, then issuing a BGSAVE command and checking at regular intervals every N seconds if LASTSAVE changed.

Returns:

Integer reply, specifically an UNIX time stamp.

shutdown

public String shutdown()

Synchronously save the DB on disk, then shutdown the server.

Stop all the clients, save the DB, then quit the server. This commands makes sure that the DB is switched off without the lost of any data. This is not guaranteed if the client uses simply SAVE and then QUIT because other clients may alter the DB data between the two commands.

Returns:

Status code reply on error. On success nothing is returned since the server quits and the connection is closed.

info

public String info()

Provide information and statistics about the server.

The info command returns different information and statistics about the server in an format that's simple to parse by computers and easy to read by humans.

Format of the returned String:

All the fields are in the form field:value

 edis_version:0.07
 connected_clients:1
 connected_slaves:0
 used_memory:3187
 changes_since_last_save:0
 last_save_time:1237655729
 total_connections_received:1
 total_commands_processed:1
 uptime_in_seconds:25
 uptime_in_days:0
 

Notes

used_memory is returned in bytes, and is the total number of bytes allocated by the program using malloc.

uptime_in_days is redundant since the uptime in seconds contains already the full uptime information, this field is only mainly present for humans.

changes_since_last_save does not refer to the number of key changes, but to the number of operations that produced some kind of change in the dataset.

Returns:

Bulk reply

monitor

public void monitor(JedisMonitor jedisMonitor)

Dump all the received requests in real time.

MONITOR is a debugging command that outputs the whole sequence of commands received by the Redis server. is very handy in order to understand what is happening into the database. This command is used directly via telnet.

Parameters:

jedisMonitor -

slaveof

public String slaveof(String host,
                      int port)

Change the replication settings.

The SLAVEOF command can change the replication settings of a slave on the fly. If a Redis server is arleady acting as slave, the command SLAVEOF NO ONE will turn off the replicaiton turning the Redis server into a MASTER. In the proper form SLAVEOF hostname port will make the server a slave of the specific server listening at the specified hostname and port.

If a server is already a slave of some master, SLAVEOF hostname port will stop the replication against the old server and start the synchrnonization against the new one discarding the old dataset.

The form SLAVEOF no one will stop replication turning the server into a MASTER but will not discard the replication. So if the old master stop working it is possible to turn the slave into a master and set the application to use the new master in read/write. Later when the other Redis server will be fixed it can be configured in order to work as slave.

Parameters:

host -

port -

Returns:

Status code reply

slaveofNoOne

public String slaveofNoOne()

configGet

public List<String> configGet(String pattern)

Retrieve the configuration of a running Redis server. Not all the configuration parameters are supported.

CONFIG GET returns the current configuration parameters. This sub command only accepts a single argument, that is glob style pattern. All the configuration parameters matching this parameter are reported as a list of key-value pairs.

Example:

 $ redis-cli config get '*'
 1. "dbfilename"
 2. "dump.rdb"
 3. "requirepass"
 4. (nil)
 5. "masterauth"
 6. (nil)
 7. "maxmemory"
 8. "0\n"
 9. "appendfsync"
 10. "everysec"
 11. "save"
 12. "3600 1 300 100 60 10000"
 
 $ redis-cli config get 'm*'
 1. "masterauth"
 2. (nil)
 3. "maxmemory"
 4. "0\n"
 

Parameters:

pattern -

Returns:

Bulk reply.

configSet

public String configSet(String parameter,
                        String value)

Alter the configuration of a running Redis server. Not all the configuration parameters are supported.

The list of configuration parameters supported by CONFIG SET can be obtained issuing a CONFIG GET * command.

The configuration set using CONFIG SET is immediately loaded by the Redis server that will start acting as specified starting from the next command.

Parameters value format

The value of the configuration parameter is the same as the one of the same parameter in the Redis configuration file, with the following exceptions:

• The save paramter is a list of space-separated integers. Every pair of integers specify the time and number of changes limit to trigger a save. For instance the command CONFIG SET save "3600 10 60 10000" will configure the server to issue a background saving of the RDB file every 3600 seconds if there are at least 10 changes in the dataset, and every 60 seconds if there are at least 10000 changes. To completely disable automatic snapshots just set the parameter as an empty string.
• All the integer parameters representing memory are returned and accepted only using bytes as unit.

Parameters:

parameter -

value -

Returns:

Status code reply

isConnected

public boolean isConnected()

strlen

public Integer strlen(String key)

sync

public void sync()

lpushx

public Integer lpushx(String key,
                      String string)

persist

public Integer persist(String key)

Undo a expire at turning the expire key into a normal key.

Time complexity: O(1)

Parameters:

key -

Returns:

Integer reply, specifically: 1: the key is now persist. 0: the key is not persist (only happens when key not set).

rpushx

public Integer rpushx(String key,
                      String string)

echo

public String echo(String string)

linsert

public Integer linsert(String key,
                       Client.LIST_POSITION where,
                       String pivot,
                       String value)

debug

public String debug(DebugParams params)