SpringJDBC多数据源配置

提示：本文章代码基本来自gitbook.cn的教程《精通Sringboot 42 讲》，作者纯洁的微笑。我写这篇文章的原因是因为原文代码直接在本地跑不通，需要添加一些代码，做一些修改才能完美运行，所以将修改后的版本分享出来，原教程还是不错的，附上链接精通springboot42讲。

涉及的maven依赖：

	org.springframework.boot
	spring-boot-starter-jdbc


	mysql
	mysql-connector-java


	com.alibaba
	druid
	1.0.9

application.properties中数据源的配置：

spring.datasource.primary.jdbc-url=jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
spring.datasource.primary.username=root
spring.datasource.primary.password=
spring.datasource.primary.driver-class-name=com.mysql.cj.jdbc.Driver

spring.datasource.secondary.jdbc-url=jdbc:mysql://localhost:3306/test2?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
spring.datasource.secondary.username=root
spring.datasource.secondary.password=
spring.datasource.secondary.driver-class-name=com.mysql.cj.jdbc.Driver

多数据源配置类：

import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
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 DataSourceConfig {
    @Primary
    @Bean(name = "primaryDataSource")
    @Qualifier("primaryDataSource")
    @ConfigurationProperties(prefix="spring.datasource.primary")
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "secondaryDataSource")
    @Qualifier("secondaryDataSource")
    @ConfigurationProperties(prefix="spring.datasource.secondary")
    public DataSource secondaryDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Primary//注意这里要加此注解以免依赖冲突
    @Bean(name="primaryJdbcTemplate")
    public JdbcTemplate primaryJdbcTemplate (
            @Qualifier("primaryDataSource")  DataSource dataSource ) {
        return new JdbcTemplate(dataSource);
    }

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

建表sql:

DROP TABLE IF EXISTS `users`;
CREATE TABLE `users` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '主键id',
  `name` varchar(32) DEFAULT NULL COMMENT '用户名',
  `password` varchar(32) DEFAULT NULL COMMENT '密码',
  `age`  int DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

实体类：

public class User {
    private Long id;
    private String name;
    private String password;
    private int age;

    public User() {
    }

    public User(String name, String password, int age) {
        this.name = name;
        this.password = password;
        this.age = age;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", password='" + password + '\'' +
                ", age=" + age +
                '}';
    }
}

 

数据库访问层接口与实现：

接口：

public interface UserRepository {
    int save(User user,JdbcTemplate jdbcTemplate);
}

实现：

import com.kbdct.hello.jdbcL.entity.User;
import com.kbdct.hello.jdbcL.entity.UserRowMapper;
import com.kbdct.hello.jdbcL.resposity.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;
import java.util.List;

@Repository
public class UserRepositoryImpl implements UserRepository{

    @Autowired
    private JdbcTemplate primaryJdbcTemplate;

    public int save(User user,JdbcTemplate jdbcTemplate) {
        if(jdbcTemplate == null){
            System.out.println("jdbcTemplate is null");
            jdbcTemplate= primaryJdbcTemplate;
        }
        return jdbcTemplate.update("INSERT INTO users(name, password, age) values(?, ?, ?)",
                user.getName(), user.getPassword(), user.getAge());
    }
}

测试例：

import com.kbdct.hello.jdbcL.entity.User;
import com.kbdct.hello.jdbcL.resposity.UserRepository;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.test.context.junit4.SpringRunner;
import javax.annotation.Resource;
import java.util.List;

@RunWith(SpringRunner.class)
@SpringBootTest
public class UserRepositoryTest {
    @Autowired
    private UserRepository userRepository;

    @Resource(name="primaryJdbcTemplate")//注意要用byname的方式注入
    private JdbcTemplate primaryJdbcTemplate;

    @Resource(name="secondaryJdbcTemplate")//注意要用byname的方式注入
    private JdbcTemplate secondaryJdbcTemplate;

    @Test
    public void testSave2() {
        User user =new User("smile","123456",30);
        System.out.println("before call primaryJdbcTemplate");
        userRepository.save(user,primaryJdbcTemplate);
        System.out.println("before call secondaryJdbcTemplate");
        userRepository.save(user,secondaryJdbcTemplate);
    }
}

运行完测试例后可在两个数据库中看到插入的记录。

注意，如果是配置单数据源，一定要记得在主类中添加数据源的配置：

import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.core.env.Environment;

import javax.sql.DataSource;

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
public class HelloApplication {

	public static void main(String[] args) {
		SpringApplication.run(HelloApplication.class, args);
	}

	@Autowired
	private Environment env;

	@Bean
	public DataSource dataSource() {
		DruidDataSource dataSource = new DruidDataSource();
		dataSource.setUrl(env.getProperty("spring.datasource.url"));
		dataSource.setUsername(env.getProperty("spring.datasource.username"));//用户名
		dataSource.setPassword(env.getProperty("spring.datasource.password"));//密码
		dataSource.setDriverClassName(env.getProperty("spring.datasource.driver-class-name"));
		dataSource.setInitialSize(2);//初始化时建立物理连接的个数
		dataSource.setMaxActive(20);//最大连接池数量
		dataSource.setMinIdle(0);//最小连接池数量
		dataSource.setMaxWait(60000);//获取连接时最大等待时间，单位毫秒。
		dataSource.setValidationQuery("SELECT 1");//用来检测连接是否有效的sql
		dataSource.setTestOnBorrow(false);//申请连接时执行validationQuery检测连接是否有效
		dataSource.setTestWhileIdle(true);//建议配置为true，不影响性能，并且保证安全性。
		dataSource.setPoolPreparedStatements(false);//是否缓存preparedStatement，也就是PSCache
		return dataSource;
	}
}

最后BB:

过去的两个月公司项目赶进度，我比较忙碌，没有写总结文章了，也偷懒了两个月下班后没学什么东西，这种状态可不行，我要stay hungry，我要学学学！但是过去两个月也不是完全没收获，写了一套hive查询让我对大数据环境的运行与使用有了一定了解，还是挺高兴的。