springboot集成jpa使用 sharding-jdbc进行数据库分片

一、集成jpa

这篇文章 从上篇文章：

springboot 集成jpa

基础上修改而来，所以首先数据库orm还是使用jpa，连接池也还是使用druid。
这部分内容不变

二、修改pom 依赖项

在上一篇的基础上，需要添加 sharding-jdbc的依赖，完整的pom如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.0.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.xyzh</groupId>
    <artifactId>jpademo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>jpademo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <sharding-sphere.version>4.0.0-RC1</sharding-sphere.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
            <version>${sharding-sphere.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-namespace</artifactId>
            <version>${sharding-sphere.version}</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

三、准备数据库

数据库整体结构如下图：

建库语句如下：
ds0.sql:

-- ----------------------------
-- Table structure for t_order_0
-- ----------------------------
DROP TABLE IF EXISTS `t_order_0`;
CREATE TABLE `t_order_0` (
  `order_id` bigint(50) NOT NULL AUTO_INCREMENT,
  `user_id` bigint(50) NOT NULL,
  `status` varchar(50) DEFAULT NULL,
  PRIMARY KEY (`order_id`)
) ENGINE=InnoDB AUTO_INCREMENT=8014416105477508505 DEFAULT CHARSET=utf8mb4;

-- ----------------------------
-- Table structure for t_order_1
-- ----------------------------
DROP TABLE IF EXISTS `t_order_1`;
CREATE TABLE `t_order_1` (
  `order_id` bigint(50) NOT NULL AUTO_INCREMENT,
  `user_id` bigint(50) NOT NULL,
  `status` varchar(50) DEFAULT NULL,
  PRIMARY KEY (`order_id`)
) ENGINE=InnoDB AUTO_INCREMENT=779413670294733471 DEFAULT CHARSET=utf8mb4;

ds1.sql

-- ----------------------------
-- Table structure for t_order_0
-- ----------------------------
DROP TABLE IF EXISTS `t_order_0`;
CREATE TABLE `t_order_0` (
  `order_id` bigint(50) NOT NULL AUTO_INCREMENT,
  `user_id` bigint(50) NOT NULL,
  `status` varchar(50) DEFAULT NULL,
  PRIMARY KEY (`order_id`)
) ENGINE=InnoDB AUTO_INCREMENT=779413662241669402 DEFAULT CHARSET=utf8mb4;

-- ----------------------------
-- Table structure for t_order_1
-- ----------------------------
DROP TABLE IF EXISTS `t_order_1`;
CREATE TABLE `t_order_1` (
  `order_id` bigint(50) NOT NULL AUTO_INCREMENT,
  `user_id` bigint(50) NOT NULL,
  `status` varchar(50) DEFAULT NULL,
  PRIMARY KEY (`order_id`)
) ENGINE=InnoDB AUTO_INCREMENT=779413616725082962 DEFAULT CHARSET=utf8mb4;

四、修改配置文件

server.port=8071
spring.application.name=jpademo
spring.main.allow-bean-definition-overriding=true
spring.jpa.database=mysql
#spring.jpa.database-platform=org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true

spring.shardingsphere.datasource.names=ds0,ds1
spring.shardingsphere.datasource.ds0.type=com.alibaba.druid.pool.DruidDataSource
spring.shardingsphere.datasource.ds0.driver-class-name=com.mysql.cj.jdbc.Driver
spring.shardingsphere.datasource.ds0.url=jdbc:mysql://172.30.100.194:3306/ds0?useUnicode=true&characterEncoding=UTF-8
spring.shardingsphere.datasource.ds0.username=root
spring.shardingsphere.datasource.ds0.password=Root,123

spring.shardingsphere.datasource.ds1.type=com.alibaba.druid.pool.DruidDataSource
spring.shardingsphere.datasource.ds1.driver-class-name=com.mysql.cj.jdbc.Driver
spring.shardingsphere.datasource.ds1.url=jdbc:mysql://172.30.100.194:3306/ds1?useUnicode=true&characterEncoding=UTF-8
spring.shardingsphere.datasource.ds1.username=root
spring.shardingsphere.datasource.ds1.password=Root,123

spring.shardingsphere.sharding.default-database-strategy.inline.sharding-column=order_id
spring.shardingsphere.sharding.default-database-strategy.inline.algorithm-expression=ds$->{order_id % 2}


spring.shardingsphere.sharding.tables.t_order.actual-data-nodes=ds$->{0..1}.t_order_$->{0..1}
spring.shardingsphere.sharding.tables.t_order.table-strategy.inline.sharding-column=user_id
spring.shardingsphere.sharding.tables.t_order.table-strategy.inline.algorithm-expression=t_order_$->{user_id % 2}
spring.shardingsphere.sharding.tables.t_order.key-generator.column=order_id
spring.shardingsphere.sharding.tables.t_order.key-generator.type=SNOWFLAKE

这是根据pom里面的依赖项，设置数据库连接方式、分表分库策略，基本都是按照id的一个奇偶性，这里没有用到别的特性，实际应用时，可以选择别的方式

五、修改实体类

import lombok.Data;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

@Data
@Entity
@Table(name="t_order")
public class TOrder0 {

  @Id
  private long orderId;
  private long userId;
  private String status;


  public long getOrderId() {
    return orderId;
  }

  public void setOrderId(long orderId) {
    this.orderId = orderId;
  }


  public long getUserId() {
    return userId;
  }

  public void setUserId(long userId) {
    this.userId = userId;
  }


  public String getStatus() {
    return status;
  }

  public void setStatus(String status) {
    this.status = status;
  }

}

其实这里就修改了一行，就是把 @Table中的name的值修改了下

六、修改controller

因为考虑到在 配置文件中用到了

spring.shardingsphere.sharding.tables.t_order.key-generator.type=SNOWFLAKE

这里说明下，这是在做数据分片时，对于id的取值，sharding采用的是内置的分布式数据。所以我们修改了controller，不再在controller里面 设置orderid的取值
如下：

import com.xyzh.jpademo.entity.TOrder0;
import com.xyzh.jpademo.service.IOrderService;
import net.bytebuddy.asm.Advice;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloController {

    @Autowired
    IOrderService orderService;

    @RequestMapping(value = "/hello",method = RequestMethod.GET)
    public String hello(){
        TOrder0 order0=new TOrder0();
        //order0.setOrderId(id);
        order0.setStatus("test");
        order0.setUserId(1L);
        orderService.insert(order0);

        return  "";
    }
}

七、运行程序，查看结果

数据库结果：

另外，为了加强这个分布式的id的生成算法，从网上下载了 id的生成类。可以下载