Spring Boot中双不同数据源Hikari连接池的配置方法及可行性咨询

当然可以搞定！我之前帮好几个同事配置过Spring Boot里多数据源的Hikari连接池，用application.properties配合几个简单的配置类就能实现，下面一步步给你说清楚：

我们用不同的前缀区分两个数据源，比如primary（主数据源）和secondary（次数据源），把Hikari的专属配置也一起加上：

# 主数据源配置
spring.datasource.primary.url=jdbc:mysql://localhost:3306/db_primary?useSSL=false&serverTimezone=UTC
spring.datasource.primary.username=root
spring.datasource.primary.password=your_password
spring.datasource.primary.driver-class-name=com.mysql.cj.jdbc.Driver
# 主数据源的Hikari连接池配置
spring.datasource.primary.hikari.maximum-pool-size=10
spring.datasource.primary.hikari.minimum-idle=2
spring.datasource.primary.hikari.connection-timeout=30000
spring.datasource.primary.hikari.idle-timeout=600000

# 次数据源配置
spring.datasource.secondary.url=jdbc:mysql://localhost:3306/db_secondary?useSSL=false&serverTimezone=UTC
spring.datasource.secondary.username=root
spring.datasource.secondary.password=your_password
spring.datasource.secondary.driver-class-name=com.mysql.cj.jdbc.Driver
# 次数据源的Hikari连接池配置
spring.datasource.secondary.hikari.maximum-pool-size=8
spring.datasource.secondary.hikari.minimum-idle=1
spring.datasource.secondary.hikari.connection-timeout=30000
spring.datasource.secondary.hikari.idle-timeout=600000

需要创建两个配置类，分别绑定上面的配置，并且指定主数据源（避免Spring自动装配时冲突）：

主数据源配置类 #

import com.zaxxer.hikari.HikariDataSource;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import javax.sql.DataSource;

@Configuration
public class PrimaryDataSourceConfig {

    @Primary
    @Bean(name = "primaryDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.primary")
    public DataSource primaryDataSource() {
        // Spring Boot会自动把Hikari的配置绑定到这个DataSource里
        return new HikariDataSource();
    }
}

次数据源配置类 #

import com.zaxxer.hikari.HikariDataSource;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;

@Configuration
public class SecondaryDataSourceConfig {

    @Bean(name = "secondaryDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.secondary")
    public DataSource secondaryDataSource() {
        return new HikariDataSource();
    }
}

如果用JdbcTemplate来操作两个库，需要为每个数据源单独创建JdbcTemplate Bean：

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.core.JdbcTemplate;

import javax.sql.DataSource;

@Configuration
public class JdbcTemplateConfig {

    @Primary
    @Bean(name = "primaryJdbcTemplate")
    public JdbcTemplate primaryJdbcTemplate(DataSource primaryDataSource) {
        return new JdbcTemplate(primaryDataSource);
    }

    @Bean(name = "secondaryJdbcTemplate")
    public JdbcTemplate secondaryJdbcTemplate(DataSource secondaryDataSource) {
        return new JdbcTemplate(secondaryDataSource);
    }
}

在业务代码里，用@Qualifier注解指定要使用哪个JdbcTemplate（或数据源）：

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;

@Service
public class DataService {

    private final JdbcTemplate primaryJdbcTemplate;
    private final JdbcTemplate secondaryJdbcTemplate;

    // 构造注入，用@Qualifier指定Bean名称
    public DataService(@Qualifier("primaryJdbcTemplate") JdbcTemplate primaryJdbcTemplate,
                       @Qualifier("secondaryJdbcTemplate") JdbcTemplate secondaryJdbcTemplate) {
        this.primaryJdbcTemplate = primaryJdbcTemplate;
        this.secondaryJdbcTemplate = secondaryJdbcTemplate;
    }

    public void queryPrimaryDb() {
        String sql = "SELECT * FROM users";
        primaryJdbcTemplate.query(sql, (rs, rowNum) -> rs.getString("username"));
    }

    public void querySecondaryDb() {
        String sql = "SELECT * FROM orders";
        secondaryJdbcTemplate.query(sql, (rs, rowNum) -> rs.getInt("order_id"));
    }
}

注意事项 #

• 一定要给主数据源加上@Primary注解，不然Spring不知道该默认用哪个，会抛出歧义错误
• @ConfigurationProperties的前缀要和application.properties里的完全对应，这样Hikari的所有配置才会自动绑定
• 如果用JPA而不是JdbcTemplate，只需要把JdbcTemplate的配置换成EntityManagerFactory和TransactionManager的配置就行，思路是一样的

内容的提问来源于stack exchange，提问作者gcpdev-guy