最近在一个需要中需要去连接其他的项目的数据库，本来想使用jbdc直接链接下的，反正就是获取数据，但是想想还是算了，正好springboot数据源配置还没有玩过，那么就正好趁这次机会学习并使用下
至于pom文件需要的依赖自然不必多说。直接从yml文件说起
1 spring:
2 datasource:
3 druid:
4 master:
5 driver-class-name: com.mysql.cj.jdbc.Driver
6 url: jdbc:mysql://xxxx:3306/test?useUnicode=true&characterEncoding=utf8&useSSL=false
7 username: root
8 password: 111111
9 slave:
10 url: jdbc:mysql://yyyy:3306/test?useUnicode=true&characherEncoding=utf-8&useSSL=false
11 username: root
12 password: 111111
13 driver-class-name: com.mysql.cj.jdbc.Driver
14 db-type: com.alibaba.druid.pool.DruidDataSource
15 initial-size: 50
16 min-idle: 50
17 max-active: 100
18 max-wait: 60000
19 time-between-eviction-runs-millis: 60000
注意其中加粗的部分：
master表示主数据源，slave表示从数据源。公共的部分可以直接写在druid节点下面。下面需要注意的时候针对不同的数据源需要有不同的配置文件
主数据源的配置类
1 package com.test;
2
3 import com.alibaba.druid.pool.DruidDataSource;
4 import org.apache.ibatis.session.SqlSessionFactory;
5 import org.mybatis.spring.SqlSessionFactoryBean;
6 import org.mybatis.spring.annotation.MapperScan;
7 import org.springframework.beans.factory.annotation.Autowired;
8 import org.springframework.beans.factory.annotation.Value;
9 import org.springframework.context.annotation.Bean;
10 import org.springframework.context.annotation.Configuration;
11 import org.springframework.context.annotation.Primary;
12 import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
13 import org.springframework.jdbc.datasource.DataSourceTransactionManager;
14
15 import javax.sql.DataSource;
16
17 @Configuration
18 // 扫描 Mapper 接口并容器管理
19 @MapperScan(basePackages = MasterDataSourceConfig.PACKAGE, sqlSessionFactoryRef = "masterSqlSessionFactory")
20 public class MasterDataSourceConfig {
21
22 //mapper接口文件存放的目录 精确到 master 目录，以便跟其他数据源隔离
23 static final String PACKAGE = "com.test.mapper.master";
24 static final String MAPPER_LOCATION = "classpath:mapper/master/*.xml";
25
26 @Value("${spring.datasource.druid.master.url}")
27 private String url;
28
29 @Value("${spring.datasource.druid.master.username}")
30 private String user;
31
32 @Value("${spring.datasource.druid.master.password}")
33 private String password;
34
35 @Value("${spring.datasource.druid.master.driver-class-name}")
36 private String driverClass;
37
38 /**
39 * 默认数据源
40 * @return
41 */
43 @Bean
44 @Primary
45 public DataSource masterDataSource() {
46 DruidDataSource dataSource = new DruidDataSource();
47 dataSource.setDriverClassName(driverClass);
48 dataSource.setUrl(url);
49 dataSource.setUsername(user);
50 dataSource.setPassword(password);
51 return dataSource;
52 }
53
54 //@Bean(name = "masterTransactionManager")
55 @Bean
56 @Primary
57 public DataSourceTransactionManager masterTransactionManager() {
58 return new DataSourceTransactionManager(masterDataSource());
59 }
60
61
62 @Bean
63 @Primary
64 public SqlSessionFactory masterSqlSessionFactory(@Autowired DataSource masterDataSource)
65 throws Exception {
66 final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
67 sessionFactory.setDataSource(masterDataSource);
68 sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
69 .getResources(MasterDataSourceConfig.MAPPER_LOCATION));
70 return sessionFactory.getObject();
71 }
72 }
从数据源的配置类
1 package com.test;
2
3 import com.alibaba.druid.pool.DruidDataSource;
4 import org.apache.ibatis.session.SqlSessionFactory;
5 import org.mybatis.spring.SqlSessionFactoryBean;
6 import org.mybatis.spring.annotation.MapperScan;
7 import org.springframework.beans.factory.annotation.Autowired;
8 import org.springframework.beans.factory.annotation.Value;
9 import org.springframework.context.annotation.Bean;
10 import org.springframework.context.annotation.Configuration;
11 import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
12 import org.springframework.jdbc.datasource.DataSourceTransactionManager;
13
14 import javax.sql.DataSource;
15
16
17 @Configuration
18 // 扫描 Mapper 接口并容器管理
19 @MapperScan(basePackages = SlaveDataSourceConfig.PACKAGE, sqlSessionFactoryRef = "slaveSqlSessionFactory")
20 public class SlaveDataSourceConfig {
21
22 //mapper接口文件的存放目录 精确到 slave目录，以便跟其他数据源隔离
23 static final String PACKAGE = "com.test.mapper.slave";
24 static final String MAPPER_LOCATION = "classpath:mapper/slave/*.xml";
25
26 @Value("${spring.datasource.druid.slave.url}")
27 private String url;
28
29 @Value("${spring.datasource.druid.slave.username}")
30 private String user;
31
32 @Value("${spring.datasource.druid.slave.password}")
33 private String password;
34
35 @Value("${spring.datasource.druid.slave.driver-class-name}")
36 private String driverClass;
37
38
39 @Bean
40 public DataSource slaveDataSource() {
41 DruidDataSource dataSource = new DruidDataSource();
42 dataSource.setDriverClassName(driverClass);
43 dataSource.setUrl(url);
44 dataSource.setUsername(user);
45 dataSource.setPassword(password);
46 return dataSource;
47 }
48
49
50 @Bean
51 public DataSourceTransactionManager slaveTransactionManager() {
52 return new DataSourceTransactionManager(slaveDataSource());
53 }
54
55
56 @Bean
57 public SqlSessionFactory slaveSqlSessionFactory(@Autowired DataSource slaveDataSource)
58 throws Exception {
59 final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
60 sessionFactory.setDataSource(slaveDataSource);
61 sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
62 .getResources(SlaveDataSourceConfig.MAPPER_LOCATION));
63 return sessionFactory.getObject();
64 }
65 }
总结：上面的配置类的位置是随便放的，方式MappSacan的位置需要注意，数据源扫描哪个mapper目录。那么该mapper目录就默认使用当前是数据源
