springboot使用DynamicDataSource动态切换数据源的实现过程

public class DynamicDataSource extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return DynamicDataSourceContextHolder.getDataSourceName();
    }
    public DynamicDataSource(DataSource defaultTargetDataSource, Map<Object, Object> targetDataSources) {
        super.setDefaultTargetDataSource(defaultTargetDataSource);
        super.setTargetDataSources(targetDataSources);
        super.afterPropertiesSet();
    }
}

public class DynamicDataSourceContextHolder {
    private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();
    /**
     * 设置当前数据源的名称
     */
    public static void setDataSourceName(String dataSourceName) {
        contextHolder.set(dataSourceName);
    }
    /**
     * 获取当前数据源的名称
     */
    public static String getDataSourceName() {
        return contextHolder.get();
    }
    /**
     * 清除当前数据源的名称
     */
    public static void clearDataSourceName() {
        contextHolder.remove();
    }
}

spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://****:3306/emp_ts?nullNamePatternMatchesAll=true&tinyInt1isBit=false&useSSL=false&nullCatalogMeansCurrent=true&useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8
    username: root
    password: root
mutil-datasource:
  connection:
    - dbName: dataSource1
      dbDriver: com.mysql.cj.jdbc.Driver
      dbUrl: jdbc:mysql://****:3306/emp_ts_1?nullNamePatternMatchesAll=true&tinyInt1isBit=false&useSSL=false&nullCatalogMeansCurrent=true&useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8
      dbUsername: root
      dbPassword: root

public class DbConnection {
    private String dbName;
    private String dbDialect;
    private String dbDriver;
    private String dbUrl;
    private String dbUsername;
    private String dbPassword;
    public DbConnection() {
    }
    public String getDbName() {
        return this.dbName;
    }
    public String getDbDialect() {
        return this.dbDialect;
    }
    public String getDbDriver() {
        return this.dbDriver;
    }
    public String getDbUrl() {
        return this.dbUrl;
    }
    public String getDbUsername() {
        return this.dbUsername;
    }
    public String getDbPassword() {
        return this.dbPassword;
    }
    public void setDbName(String dbName) {
        this.dbName = dbName;
    }
    public void setDbDialect(String dbDialect) {
        this.dbDialect = dbDialect;
    }
    public void setDbDriver(String dbDriver) {
        this.dbDriver = dbDriver;
    }
    public void setDbUrl(String dbUrl) {
        this.dbUrl = dbUrl;
    }
    public void setDbUsername(String dbUsername) {
        this.dbUsername = dbUsername;
    }
    public void setDbPassword(String dbPassword) {
        this.dbPassword = dbPassword;
    }
}

@Configuration
@ConfigurationProperties(
    prefix = "mutil-datasource"
)
public class MutilDataSourceProperties {
    private List<DbConnection> connection = new ArrayList();
    public MutilDataSourceProperties() {
    }
    public List<DbConnection> getConnection() {
        return this.connection;
    }
    public void setConnection(List<DbConnection> connection) {
        this.connection = connection;
    }
}

@Configuration
public class DataSourceConfig {
    @Resource
    private MutilDataSourceProperties mutilDataSourceProperties;
    public DataSourceConfig() {
    }
    @Bean
    @ConfigurationProperties("spring.datasource")
    public DataSource hikariDataSource(DataSourceProperties properties) {
        return DataSourceBuilder.create(properties.getClassLoader()).driverClassName(properties.determineDriverClassName()).url(properties.determineUrl()).username(properties.determineUsername()).password(properties.determinePassword()).build();
    }
    @Bean
    @Primary
    public DynamicDataSource dynamicDataSource(DataSource hikariDataSource) {
        Map<Object, Object> targetDataSources = this.createTargetDataSource();
        return new DynamicDataSource(hikariDataSource, targetDataSources);
    }
     private Map<Object, Object> createTargetDataSource() {
        Map<Object, Object> targetDataSources = new HashMap();
        List<DbConnection> connections = this.mutilDataSourceProperties.getConnection();
        connections.forEach(e -> {
            DataSource dataSource = this.createDataSource(e);
            targetDataSources.put(e.getDbName(), dataSource);
        });
        return targetDataSources;
     }
     public DataSource createDataSource(DbConnection connection) {
        return DataSourceBuilder.create().driverClassName(connection.getDbDriver()).url(connection.getDbUrl())
                .username(connection.getDbName()).password(connection.getDbPassword()).build();
     }
}

@Service
public class UserServiceImpl implements UserService {
    @Autowired
    private UserMapper userMapper;
    @Override
    public void addUser(User user) {
        DynamicDataSource.setDataSource("dataSource1");
        userMapper.insert(user);
    }
    @Override
    public void updateUser(User user) {
        DynamicDataSource.setDataSource("dataSource1");
        userMapper.updateById(user);
    }
}