introduction

In our life, ID is actually inseparable from our life.

ID card number, QQ, mobile phone number, bank card number, student ID number, even the number lying on your hard disk.

These ID marks are so important that every background programmer has to think about this problem? What are the advantages and disadvantages?

This article takes you to learn several common ID generation strategies in simple terms.

Introductory learning

Due to space priority, it is recommended to read the following article.

Distributed ID generation requirements

UUID strategy explanation

Random generation strategy

Explanation of snowflake algorithm

ID is a common ID implementation strategy for Java design.

So that you can use it out of the box in daily development and enjoy the happiness of leaving work early~

For ID generation, all background systems must face the problem, distributed ID generation is also a very common requirement.

Recently, the code written by my colleagues, in multiple machines and issued a serial number conflict.

I think Id strategies should be aggregated into a toolkit instead of building wheels every time. Sometimes there are problems.

<dependency>
    <groupId>com.github.houbb</groupId>
    <artifactId>id</artifactId>
    <version>0.0.2</version>
</dependency>

final String snowflake = IdHelper.snowflake();

System.out.println(snowflake);

1260199310461505537

All IDS can be accessed through theIdHelperCall directly.

Serial number	method	example
1	uuid8()	dUlmJiEq
2	uuid32()	3f9afd5773d143fb8e28d80de47f3d1a
3	random()	202005122127270743937635635
4	random(prefix, length)	`random("999", 5)`It is 9992020051221340961522263
5	snowflake()	1260199914969849858
6	local()	Starting from 0, gradually add 1 to return the ID