Java redis operation details

1. Introduction

Redis is an open source (BSD licensed) in memory key value storage system, which can be used as database, cache and message middleware.

2. Operation on key

First, establish the connection jedis jedis = new jedis ("127.0.0.1", 6379), and then operate on string, set, Zset and hash.

3. String data type

The Java operation code is:

4. List data type

Lists in redis is not an array but a linked list in the underlying implementation.

A series of operations: rpush, lpush, llen, lrange, lpop and rpop.

We can use lpush to insert a new element on the left side of lists, rpush to insert a new element on the right side of lists, and lrange to specify a range from lists to extract elements.

The Java operation code is:

5. Set type

The redis collection is an unordered collection. The elements in the collection have no order. A series of operations: Sadd, SREM, sismember, smembers and Sunion Set related operations are also very rich, such as adding new elements, deleting existing elements, taking intersection sets, taking union sets, taking difference sets, etc.

Java operation code:

6. Sorted sets type

We all call the ordered sets in redis zsets

The Java operation code is:

7. Hash type

Hashes stores the mapping between strings and string values

Java operation code:

8. Services

Transaction refers to "a complete action, either all performed or nothing done". Before talking about redis transaction processing, I'd like to introduce four redis instructions, namely multi, exec, discard and watch. These four instructions form the basis of redis transaction processing.

1. Multi is used to assemble a transaction; 2. Exec is used to execute a transaction; 3. Discard is used to cancel a transaction; 4. Watch is used to monitor some keys. Once these keys are changed before the transaction is executed, the execution of the transaction will be cancelled.

The Java operation code is:

Pipeline operation java code:

summary

The above is all about the detailed introduction of Java operation redis in this article. I hope it will be helpful to you. If there are deficiencies, please leave a message to point out. Thank you for your support.