起源:https://lilinchao.com/archive…
一、UidGenerator是什么
UidGenerator是百度开源的一款分布式高性能的惟一ID生成器,是基于snowflake模型的一种ID生成器
二、UidGenerator的劣势
- 解决了时钟回调的问题
- 应用ringbuffer,无锁进行id的生产与生产,速度十分快
- 实用于多线程,不会有单线程瓶颈
三、整合
本次通过SpringBoot2.x和MyBatis对百度UidGenerator进行整合。
3.1 UidGenerator引入
个别应用两种形式引入UidGenerator:
1)从官网下载源码作为本人我的项目的一个Module引入到我的项目中
官网地址:https://github.com/baidu/uid-…
2)互联网jar包引入(本文采取的是该种形式)
因为UidGenerator自带引入了mybatis,和本人我的项目有抵触的能够进行排除
<dependency>
<groupId>com.xfvape.uid</groupId>
<artifactId>uid-generator</artifactId>
<version>0.0.4-RELEASE</version>
</dependency>
排除抵触依赖
uid-generator中依赖了logback和mybatis。个别在我的项目搭建过程中,springboot中曾经有了logback依赖,mybatis会作为独自的依赖引入。如果版本和uid-generator中的依赖不统一的话,就会导致抵触。
排除抵触的依赖如下:
<dependency>
<groupId>com.xfvape.uid</groupId>
<artifactId>uid-generator</artifactId>
<version>0.0.4-RELEASE</version>
<exclusions>
<exclusion>
<groupId>org.slf4j</groupId>
<artifactId>log4j-over-slf4j</artifactId>
</exclusion>
<exclusion>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
</exclusion>
<exclusion>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
</exclusion>
<exclusion>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
</exclusion>
<exclusion>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
</exclusion>
</exclusions>
</dependency>
3.2 创立表
在 MySQL数据库中建一个名为 WORKER_NODE
的数据表,其 sql如下:
CREATE TABLE WORKER_NODE
(
ID BIGINT NOT NULL AUTO_INCREMENT COMMENT 'auto increment id',
HOST_NAME VARCHAR(64) NOT NULL COMMENT 'host name',
PORT VARCHAR(64) NOT NULL COMMENT 'port',
TYPE INT NOT NULL COMMENT 'node type: ACTUAL or CONTAINER',
LAUNCH_DATE DATE NOT NULL COMMENT 'launch date',
MODIFIED TIMESTAMP NOT NULL COMMENT 'modified time',
CREATED TIMESTAMP NOT NULL COMMENT 'created time',
PRIMARY KEY(ID)
)
COMMENT='DB WorkerID Assigner for UID Generator',ENGINE = INNODB;
建表时可能会报错,起因是该建表语句定义了两个TIMESTAMP字段,因为mysql 低版本控制比拟严格
解决办法:
形式一:
间接把TIMESTAMP改成DATETIME 即可
形式二:
建表前先设置sql_mode:
set sql_mode="NO_ENGINE_SUBSTITUTION";
3.3 将uid-generator外围对象拆卸为spring的bean
uid-generator提供了两种生成器: DefaultUidGenerator、CachedUidGenerator。如对UID生成性能有要求, 请应用CachedUidGenerator。
@Configuration
public class WorkerNodeConfig {
@Bean("disposableWorkerIdAssigner")
public DisposableWorkerIdAssigner disposableWorkerIdAssigner(){
DisposableWorkerIdAssigner disposableWorkerIdAssigner = new DisposableWorkerIdAssigner();
return disposableWorkerIdAssigner;
}
@Bean("cachedUidGenerator")
public UidGenerator uidGenerator(DisposableWorkerIdAssigner disposableWorkerIdAssigner){
CachedUidGenerator cachedUidGenerator = new CachedUidGenerator();
cachedUidGenerator.setWorkerIdAssigner(disposableWorkerIdAssigner);
return cachedUidGenerator;
}
}
间接创立WorkerNodeConfig类,复制以上代码。
3.4 重写WorkerIdAssigner接口
public class DisposableWorkerIdAssigner implements WorkerIdAssigner {
@Resource
private WorkerNodeMapper workerNodeMapper;
@Override
@Transactional
public long assignWorkerId() {
WorkerNode workerNode = buildWorkerNode();
workerNodeMapper.addWorkerNode(workerNode);
return workerNode.getId();
}
private WorkerNode buildWorkerNode() {
WorkerNode workNode = new WorkerNode();
if (DockerUtils.isDocker()) {
workNode.setType(WorkerNodeType.CONTAINER.value());
workNode.setHostName(DockerUtils.getDockerHost());
workNode.setPort(DockerUtils.getDockerPort());
workNode.setLaunchDate(new Date());
} else {
workNode.setType(WorkerNodeType.ACTUAL.value());
workNode.setHostName(NetUtils.getLocalAddress());
workNode.setPort(System.currentTimeMillis() + "-" + RandomUtils.nextInt(100000));
workNode.setLaunchDate(new Date());
}
return workNode;
}
}
创立一个DisposableWorkerIdAssigner类间接复制以上代码。
3.5 引入WorkerNodeMapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.uidgenerator.mapper.WorkerNodeMapper">
<resultMap id="BaseResultMap"
type="com.uidgenerator.entity.WorkerNode">
<id column="ID" jdbcType="BIGINT" property="id" />
<result column="HOST_NAME" jdbcType="VARCHAR" property="hostName" />
<result column="PORT" jdbcType="VARCHAR" property="port" />
<result column="TYPE" jdbcType="INTEGER" property="type" />
<result column="LAUNCH_DATE" jdbcType="DATE" property="launchDate" />
<result column="MODIFIED" jdbcType="TIMESTAMP" property="modified" />
<result column="CREATED" jdbcType="TIMESTAMP" property="created" />
</resultMap>
<insert id="addWorkerNode" useGeneratedKeys="true" keyProperty="id"
parameterType="com.uidgenerator.entity.WorkerNode">
INSERT INTO WORKER_NODE
(HOST_NAME,
PORT,
TYPE,
LAUNCH_DATE,
MODIFIED,
CREATED)
VALUES (
#{hostName},
#{port},
#{type},
#{launchDate},
NOW(),
NOW())
</insert>
<select id="getWorkerNodeByHostPort" resultMap="BaseResultMap ">
SELECT
ID,
HOST_NAME,
PORT,
TYPE,
LAUNCH_DATE,
MODIFIED,
CREATED
FROM
WORKER_NODE
WHERE
HOST_NAME = #{host} AND PORT = #{port}
</select>
</mapper>
能够通过mybatis生成工具间接生成文件和实体类,而后将插入和查询方法复制
留神批改resultMap中的type和insert中的keyProperty为本身我的项目的实体类地址
在application.yml文件中减少如下配置
mybatis:
mapper-locations: classpath:mybatis/*.xml
3.6实体类
应用插件生成的实体类
3.7创立Mapper
@Mapper
public interface WorkerNodeMapper {
int addWorkerNode(WorkerNode workerNodeEntity);
WorkerNode getWorkerNodeByHostPort(@Param("host") String host, @Param("port") String port);
}
3.8 Service
IWorkerNodeService接口
public interface IWorkerNodeService {
public long genUid();
}
WorkerNodeServiceImpl实现类
@Service
public class WorkerNodeServiceImpl implements IWorkerNodeService {
@Resource
private UidGenerator uidGenerator;
@Override
public long genUid() {
Long uu_id = UidGeneratorComponent.uu_id;
return uidGenerator.getUID();
}
}
3.8 Controller
@RestController
public class WorkerNodeServiceController {
@Resource
private IWorkerNodeService workerNodeService;
/**
* 集成百度uid-generator生成id
* @return
*/
@GetMapping("/baidu/uid")
public long baiduUid(){
long uid = workerNodeService.genUid();
return uid;
}
}
3.9 拜访接口测试
http://127.0.0.1:8099/test/ba…
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