springboot使用切面方式（自定义注解）动态连接多数据源
前言
springboot里面可以有多种方式配置多数据源。之前写过将mapper与指定数据源锁定，但是随着项目的扩大，动态使用多数据源已经不可避免，这些天将代码搭建好了并成功上线使用。记录以供各路大神重复造轮子。（ps:springboot版本 1.5.9）
配置以及代码
分析：动态切换数据源，我们可不可以自定义一个注解，然后在需要切换数据源的地方加上自定义的注解，让程序自动切换呢？很显然是可以的。
自定义注解：
/**
* create by liuliang
* on 2019-09-03 19:16
*/
@Target({ElementType.METHOD,ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface MFTDataSource {
DataSourceEnum value() default DataSourceEnum.DB_EXPEND;
}
注解定义好了，我们需要有一个切面，去环绕这个注解，做我们需要的增强。为了简洁方便，我将使用枚举来切换多数据源。
/**
* create by liuliang
* on 2019-09-03 19:17
*/
@Component
@Slf4j
@Aspect
@Order(-1)
public class DataSourceAspect {
@Pointcut("@within(com.meifute.expend.config.datasource.MFTDataSource) || @annotation(com.meifute.expend.config.datasource.MFTDataSource)")
public void pointCut(){
}
@Before("pointCut() && @annotation(dataSource)")
public void doBefore(MFTDataSource dataSource){
log.info("===========选择数据源=========>>> "+dataSource.value().getValue());
DataSourceContextHolder.setDataSource(dataSource.value().getValue());
}
@After("pointCut()")
public void doAfter(){
DataSourceContextHolder.clear();
}
}
枚举类：
/**
* create by liuliang
* on 2019-09-03 19:14
*/
public enum DataSourceEnum {
DB_EXPEND("expend"),DB_USER("user"),DB_AGENT("agent"),DB_ADMIN("admin");
private String value;
DataSourceEnum(String value){this.value=value;}
public String getValue() {
return value;
}
}
上面定义好了以后，我们需要使用一个线程变量，来存放当前注解所在线程的连接信息，在进入注解所在方法的时候，给线程变量赋值指定数据源连接，在结束的时候，就清理当前线程：
/**
* create by liuliang
* on 2019-09-03 19:12
*/
public class DataSourceContextHolder {
private static final ThreadLocal<String> contextHolder = new InheritableThreadLocal<>();
/**
* 设置数据源
* @param db
*/
public static void setDataSource(String db){
contextHolder.set(db);
}
/**
* 取得当前数据源
* @return
*/
public static String getDataSource(){
return contextHolder.get();
}
/**
* 清除上下文数据
*/
public static void clear(){
contextHolder.remove();
}
}
当然，我们需要把切换数据源的工作交给spring，这里继承AbstractRoutingDataSource，重写determineCurrentLookupKey方法，使用我们自定义的线程变量获取当前数据源。
/**
* create by liuliang
* on 2019-09-03 19:14
*/
public class MultipleDataSource extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
return DataSourceContextHolder.getDataSource();
}
}
当然，最重要的多数据源配置，我们可以这样配置：
@Configuration
@MapperScan("com.meifute.expend.mapper.*")
public class MyBatiesPlusConfiguration {
//expend
@Bean(name = "expend")
@ConfigurationProperties(prefix = "spring.datasource.druid.expend" )
public DataSource expend() {
DruidDataSource build = DruidDataSourceBuilder.create().build();
return build;
}
//user
@Bean(name = "user")
@ConfigurationProperties(prefix = "spring.datasource.druid.user" )
public DataSource user() {
return DruidDataSourceBuilder.create().build();
}
//agent
@Bean(name = "agent")
@ConfigurationProperties(prefix = "spring.datasource.druid.agent" )
public DataSource agent() {
return DruidDataSourceBuilder.create().build();
}
@Bean(name = "admin")
@ConfigurationProperties(prefix = "spring.datasource.druid.admin" )
public DataSource admin() {
return DruidDataSourceBuilder.create().build();
}
/**
* 动态数据源配置
* @return
*/
@Bean
@Primary
public DataSource multipleDataSource(@Qualifier("expend") DataSource expend,
@Qualifier("user") DataSource user,
@Qualifier("agent") DataSource agent,
@Qualifier("admin") DataSource admin
) {
MultipleDataSource multipleDataSource = new MultipleDataSource();
Map< Object, Object > targetDataSources = new HashMap<>();
targetDataSources.put(DataSourceEnum.DB_EXPEND.getValue(), expend);
targetDataSources.put(DataSourceEnum.DB_USER.getValue(), user);
targetDataSources.put(DataSourceEnum.DB_AGENT.getValue(), agent);
targetDataSources.put(DataSourceEnum.DB_ADMIN.getValue(), admin);
//添加数据源
multipleDataSource.setTargetDataSources(targetDataSources);
//设置默认数据源
multipleDataSource.setDefaultTargetDataSource(expend());
return multipleDataSource;
}
@Bean("sqlSessionFactory")
public SqlSessionFactory sqlSessionFactory() throws Exception {
MybatisSqlSessionFactoryBean sqlSessionFactory = new MybatisSqlSessionFactoryBean();
sqlSessionFactory.setDataSource(multipleDataSource(expend(),user(),agent(),admin()));
// sqlSessionFactory.setDataSource(db2());
sqlSessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:/mapper/*Mapper.xml"));
MybatisConfiguration configuration = new MybatisConfiguration();
//configuration.setDefaultScriptingLanguage(MybatisXMLLanguageDriver.class);
configuration.setJdbcTypeForNull(JdbcType.NULL);
configuration.setMapUnderscoreToCamelCase(true);
configuration.setCacheEnabled(false);
sqlSessionFactory.setConfiguration(configuration);
PaginationInterceptor pagination = new PaginationInterceptor();
pagination.setDialectType("mysql");
sqlSessionFactory.setPlugins(new Interceptor[]{ //PerformanceInterceptor(),OptimisticLockerInterceptor()
pagination //添加分页功能
});
return sqlSessionFactory.getObject();
}
}
@Configuration
public class DruidConfiguration {
@Bean
public ServletRegistrationBean startViewServlet(){
ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(),"/druid/*");
// IP白名单
servletRegistrationBean.addInitParameter("allow","127.0.0.1");
// IP黑名单(共同存在时，deny优先于allow)
servletRegistrationBean.addInitParameter("deny","127.0.0.1");
//控制台管理用户
servletRegistrationBean.addInitParameter("loginUsername","admin");
servletRegistrationBean.addInitParameter("loginPassword","123456");
//是否能够重置数据
servletRegistrationBean.addInitParameter("resetEnable","false");
return servletRegistrationBean;
}
@Bean
public FilterRegistrationBean statFilter(){
FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());
//添加过滤规则
filterRegistrationBean.addUrlPatterns("/*");
//忽略过滤的格式
filterRegistrationBean.addInitParameter("exclusions","*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
return filterRegistrationBean;
}
}
好了，到此代码层面就配置结束了，需要在我们的配置文件，与MyBatiesPlusConfiguration配置的对应即可（为了安全，我把关键信息隐藏了，各位大佬记得改为自己的连接方式）：
spring:
datasource:
druid:
expend:
url: jdbc:mysql://172.19.95.**:3332/mft_expend?useUnicode=true&characterEncoding=utf8
username: **
password: **
driver-class-name: com.mysql.jdbc.Driver
user:
url: jdbc:mysql://172.19.95.**:3332/m_mall_user?useUnicode=true&characterEncoding=utf8
username: **
password: **
driver-class-name: com.mysql.jdbc.Driver
agent:
url: jdbc:mysql://www.**.cn:3306/m_mall_agent?useUnicode=true&characterEncoding=utf8
username: root
password: 123456
driver-class-name: com.mysql.jdbc.Driver
admin:
url: jdbc:mysql://172.19.95.**:3332/m_mall_admin?useUnicode=true&characterEncoding=utf8
username: **
password: **
driver-class-name: com.mysql.jdbc.Driver
至此，多数据源动态切换配置结束。下面我们看一下使用方式和注意事项：
使用方式
controller:
/**
* <p>
* 用户表 前端控制器
* </p>
*
* @author liuliang
* @since 2019-09-07
*/
@Slf4j
@RestController
@RequestMapping("/expend/admin")
@Api(tags = "admin平台", value = "admin平台")
public class AdminController extends BaseController {
@Autowired
private AdminServiceImpl adminService;
@GetMapping("/test")
public void test(){
adminService.test();;
}
}
service:
/**
* <p>
* 用户表 服务实现类
* </p>
*
* @author liuliang
* @since 2019-09-07
*/
@Service
@Slf4j
public class AdminServiceImpl extends ServiceImpl<AdminMapper, Admin> implements IAdminService {
@Autowired
private MallAgentChangeLogServiceImpl changeLogService;
@Override
public void test(){
changeLogService.test1();
changeLogService.test2();
}
}
changeLogService
/**
* <p>
* 服务实现类
* </p>
*
* @author liuliang
* @since 2019-09-05
*/
@Service
@Slf4j
public class MallAgentChangeLogServiceImpl extends ServiceImpl<MallAgentChangeLogMapper, MallAgentChangeLog> implements IMallAgentChangeLogService {
@MFTDataSource(DataSourceEnum.DB_AGENT)
public void test1(){
log.info(this+"");
// adminMapper.test1();
}
@MFTDataSource(DataSourceEnum.DB_EXPEND)
public void test2(){
log.info(this+"");
// adminMapper.test2();
}
}
执行代码：通过日志我们可以看到，按照我们预期的效果动态切换了，非常棒！
2019-09-24 10:11:01,916 INFO [http-nio-5550-exec-1] [DirectJDKLog.java:179] Initializing Spring FrameworkServlet 'dispatcherServlet'
2019-09-24 10:11:01,916 INFO [http-nio-5550-exec-1] [FrameworkServlet.java:489] FrameworkServlet 'dispatcherServlet': initialization started
2019-09-24 10:11:01,949 INFO [http-nio-5550-exec-1] [FrameworkServlet.java:508] FrameworkServlet 'dispatcherServlet': initialization completed in 33 ms
2019-09-24 10:11:01,999 INFO [http-nio-5550-exec-1] [RequestLogAdvice.java:68] -----------GET-------------request[/expend/admin/test]--start--[request params：{}]----------
2019-09-24 10:11:02,012 INFO [http-nio-5550-exec-1] [DataSourceAspect.java:32] ===========选择数据源=========>>> agent
2019-09-24 10:11:02,017 INFO [http-nio-5550-exec-1] [MallAgentChangeLogServiceImpl.java:29] com.meifute.expend.service.impl.MallAgentChangeLogServiceImpl@81a56b2
2019-09-24 10:11:02,018 INFO [http-nio-5550-exec-1] [DataSourceAspect.java:32] ===========选择数据源=========>>> expend
2019-09-24 10:11:02,018 INFO [http-nio-5550-exec-1] [MallAgentChangeLogServiceImpl.java:36] com.meifute.expend.service.impl.MallAgentChangeLogServiceImpl@81a56b2
2019-09-24 10:11:02,113 INFO [http-nio-5550-exec-1] [RequestLogAdvice.java:83] ----------------------response[/expend/admin/test]--end--[耗时：19ms，response result:null, response path[/expend/admin/test]]----------
其实到这里多数据源动态连接就告一段落了，但是这里会涉及到一个知识点，我也是踩坑才爬出来的，下面记录一下：
我们看到们，刚刚我们从adminservice调用了两次ChangeLogService，如果我们直接从adminservice调用自己类里面的方法两次，会不会有同样的效果呢？测试一下：
/**
* <p>
* 用户表 服务实现类
* </p>
*
* @author liuliang
* @since 2019-09-07
*/
@Service
@Slf4j
public class AdminServiceImpl extends ServiceImpl<AdminMapper, Admin> implements IAdminService {
@Autowired
private MallAgentChangeLogServiceImpl changeLogService;
@Override
public void test(){
test1();
test2();
// changeLogService.test1();
// changeLogService.test2();
}
@MFTDataSource(DataSourceEnum.DB_AGENT)
public void test1(){
log.info(this+"");
}
@MFTDataSource(DataSourceEnum.DB_EXPEND)
public void test2(){
log.info(this+"");
}
}
其他代码不变，我们调用自己对象的两个方法后会惊奇的发现，数据源切换的aop居然一次都没有拦截到（没有打印“选择数据源=========>>> XX”）：
2019-09-24 10:16:41,738 INFO [http-nio-5550-exec-1] [DirectJDKLog.java:179] Initializing Spring FrameworkServlet 'dispatcherServlet'
2019-09-24 10:16:41,739 INFO [http-nio-5550-exec-1] [FrameworkServlet.java:489] FrameworkServlet 'dispatcherServlet': initialization started
2019-09-24 10:16:41,766 INFO [http-nio-5550-exec-1] [FrameworkServlet.java:508] FrameworkServlet 'dispatcherServlet': initialization completed in 27 ms
2019-09-24 10:16:41,917 INFO [http-nio-5550-exec-1] [RequestLogAdvice.java:68] -----------GET-------------request[/expend/admin/test]--start--[request params：{}]----------
2019-09-24 10:16:41,949 INFO [http-nio-5550-exec-1] [AdminServiceImpl.java:43] com.meifute.expend.service.impl.AdminServiceImpl@2b98c310
2019-09-24 10:16:41,950 INFO [http-nio-5550-exec-1] [AdminServiceImpl.java:50] com.meifute.expend.service.impl.AdminServiceImpl@2b98c310
2019-09-24 10:16:42,090 INFO [http-nio-5550-exec-1] [RequestLogAdvice.java:83] ----------------------response[/expend/admin/test]--end--[耗时：33ms，response result:null, response path[/expend/admin/test]]----------
到底是为什么呢？其实原因和动态代理有关。这里我给出结果和怎么处理，具体的解释大姐可以参考这位大佬的文章，解析的很详细我就不重复了。
原因：SpringAOP对于最外层的函数只拦截public方法，不拦截protected和private方法，另外不会对最外层的public方法内部调用的其他方法也进行拦截，即只停留于代理对象所调用的方法。
解决方法：
在配置文件将动态代理的bean暴露出来，然后aop获取到当前的动态代理对象，再去调用就好了（解释连接： https://www.cnblogs.com/chihi... ）：
@MapperScan("com.meifute.expend.mapper")
@SpringBootApplication
@EnableScheduling
@EnableAspectJAutoProxy(proxyTargetClass=true,exposeProxy = true)//就是这个配置！！！
public class ExpendApplication {
public static void main(String[] args) {
SpringApplication.run(ExpendApplication.class, args);
}
}
然后service使用的时候，这样获取到当前动态代理对象：
/**
* <p>
* 用户表 服务实现类
* </p>
*
* @author liuliang
* @since 2019-09-07
*/
@Service
@Slf4j
public class AdminServiceImpl extends ServiceImpl<AdminMapper, Admin> implements IAdminService {
@Autowired
private MallAgentChangeLogServiceImpl changeLogService;
@Override
public void test(){
// test1();
// test2();
// changeLogService.test1();
// changeLogService.test2();
((AdminServiceImpl)AopContext.currentProxy()).test1();
((AdminServiceImpl)AopContext.currentProxy()).test2();
}
@MFTDataSource(DataSourceEnum.DB_AGENT)
public void test1(){
log.info(this+"");
// adminMapper.test1();
}
@MFTDataSource(DataSourceEnum.DB_EXPEND)
public void test2(){
log.info(this+"");
// adminMapper.test2();
}
}
这时候，我们发现也正常的切换了：
2019-09-24 10:26:12,613 INFO [http-nio-5550-exec-1] [DirectJDKLog.java:179] Initializing Spring FrameworkServlet 'dispatcherServlet'
2019-09-24 10:26:12,613 INFO [http-nio-5550-exec-1] [FrameworkServlet.java:489] FrameworkServlet 'dispatcherServlet': initialization started
2019-09-24 10:26:12,637 INFO [http-nio-5550-exec-1] [FrameworkServlet.java:508] FrameworkServlet 'dispatcherServlet': initialization completed in 24 ms
2019-09-24 10:26:12,670 INFO [http-nio-5550-exec-1] [RequestLogAdvice.java:68] -----------GET-------------request[/expend/admin/test]--start--[request params：{}]----------
2019-09-24 10:26:12,682 INFO [http-nio-5550-exec-1] [DataSourceAspect.java:32] ===========选择数据源=========>>> agent
2019-09-24 10:26:12,683 INFO [http-nio-5550-exec-1] [AdminServiceImpl.java:44] com.meifute.expend.service.impl.AdminServiceImpl@1e987f59
2019-09-24 10:26:12,683 INFO [http-nio-5550-exec-1] [DataSourceAspect.java:32] ===========选择数据源=========>>> expend
2019-09-24 10:26:12,683 INFO [http-nio-5550-exec-1] [AdminServiceImpl.java:51] com.meifute.expend.service.impl.AdminServiceImpl@1e987f59
2019-09-24 10:26:12,719 INFO [http-nio-5550-exec-1] [RequestLogAdvice.java:83] ----------------------response[/expend/admin/test]--end--[耗时：13ms，response result:null, response path[/expend/admin/test]]----------
正文到此结束
- 本文标签： js UI App 分页 Word sqlsession HashMap 2019 classpath https 配置 CTO mybatis http mapper springboot tag 测试 ip map 代码 REST core SqlSessionFactory id druid root servlet sql API value build ORM AOP Agent web 安全 管理 key dataSource bean IO Qualifier java cat CSS XML final Service NIO Proxy spring db 线程 IDE Document 锁 文章 cache JDBC rmi db2 tar 数据 解析 解决方法 ACE plugin session mysql tab
- 版权声明： 本文为互联网转载文章，出处已在文章中说明(部分除外)。如果侵权，请联系本站长删除，谢谢。
- 本文海报： 生成海报一 生成海报二
热门推荐
相关文章
近期评论
-
文章和留言都翻到11页了 没有OOM
-
-
朋友，翻页到11页，及以后，会出现OOM，无法访问
-
-
搞个gitee的项目
-
-
版本号是多少，你可以下载哪个代码仓库，jdk选1.8 直接跑就行
-
-
-
Loading...
![[HBLOG]公众号](https://www.liuhaihua.cn/img/qrcode_gzh.jpg)
