spring boot+mybatis 多数据源切换(实例讲解)

@Retention(RetentionPolicy.RUNTIME)@Target(ElementType.METHOD)public @interface TargetDataSource { String value();//此处接收的是数据源的名称}

package com.example.demo.datasource; import com.alibaba.druid.pool.DruidDataSource;import com.alibaba.druid.support.http.StatViewServlet;import com.alibaba.druid.support.http.WebStatFilter;import com.example.demo.datasource.DynamicDataSource;import com.zaxxer.hikari.HikariConfig;import com.zaxxer.hikari.HikariDataSource;import lombok.extern.slf4j.Slf4j;import org.mybatis.spring.annotation.MapperScan;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.beans.factory.annotation.Qualifier;import org.springframework.beans.factory.annotation.Value;import org.springframework.boot.web.servlet.FilterRegistrationBean;import org.springframework.boot.web.servlet.ServletRegistrationBean;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.jdbc.datasource.DataSourceTransactionManager;import org.springframework.scheduling.annotation.EnableScheduling;import org.springframework.scheduling.annotation.Scheduled;import org.springframework.transaction.PlatformTransactionManager;import org.w3c.dom.NodeList;import org.w3c.dom.Document;import org.w3c.dom.Element;import org.w3c.dom.Node; import javax.servlet.annotation.WebInitParam;import javax.servlet.annotation.WebServlet;import javax.sql.DataSource;import javax.xml.parsers.DocumentBuilder;import javax.xml.parsers.DocumentBuilderFactory;import java.lang.reflect.Field;import java.lang.reflect.Method;import java.util.HashMap;import java.util.Map;import java.io.File;import com.alibaba.druid.support.http.StatViewServlet;/** * Author: wangchao * Version： * Date:  2017/9/11 * Description:数据源配置 * Modification History: * Date    Author    Version   Description * -------------------------------------------------------------- * Why & What is modified: */ @Configuration@EnableSchedulingpublic class DataSourceConfig {  /*@Autowired private DBProperties properties;*/ @Value("${datasource.filePath}") private String filePath;//数据源配置  @Bean(name = "dataSource") public DataSource dataSource() {  //按照目标数据源名称和目标数据源对象的映射存放在Map中  Map<Object, Object> targetDataSources = new HashMap<>();  //查找xml数据连接字符串  targetDataSources=getdataMap(filePath);  //动态获取DBProperties类申明的属性  /*Field[] fields=properties.getClass().getDeclaredFields();  for(int i=0;i<fields.length;i++)  {   targetDataSources.put(fields[i].getName(), getFieldValueByName(fields[i].getName(),properties));  }*/  //采用是想AbstractRoutingDataSource的对象包装多数据源  DynamicDataSource dataSource = new DynamicDataSource();  dataSource.setTargetDataSources(targetDataSources);  //设置默认的数据源，当拿不到数据源时，使用此配置  //dataSource.setDefaultTargetDataSource(properties.getUzaiTravel());  return dataSource; }  @Bean public PlatformTransactionManager txManager() {  return new DataSourceTransactionManager(dataSource()); }  /** *获取数据源集合 */  private Map<Object, Object> getdataMap(String fiePath) {   try {   Map<Object, Object> targetDataSources = new HashMap<>();   File xmlFile = new File(fiePath);    DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();    DocumentBuilder builder = builderFactory.newDocumentBuilder();    Document doc = builder.parse(xmlFile);    doc.getDocumentElement().normalize();    System.out.println("Root element: " + doc.getDocumentElement().getNodeName());    NodeList nList = doc.getElementsByTagName("db");   for(int i = 0 ; i<nList.getLength();i++) {     Node node = nList.item(i);    Element ele = (Element)node;     /*HikariConfig config = new HikariConfig();    config.setDriverClassName(ele.getElementsByTagName("driver-class").item(0).getTextContent());    config.setJdbcUrl(ele.getElementsByTagName("jdbc-url").item(0).getTextContent());    config.setUsername(ele.getElementsByTagName("username").item(0).getTextContent());    config.setPassword(ele.getElementsByTagName("password").item(0).getTextContent());    //config.addDataSourceProperty("password", ele.getElementsByTagName("password").item(0).getTextContent());    HikariDataSource dataSource = new HikariDataSource(config);*/      DruidDataSource dataSource = new DruidDataSource();    dataSource.setDriverClassName(ele.getElementsByTagName("driver-class").item(0).getTextContent());    dataSource.setUsername(ele.getElementsByTagName("username").item(0).getTextContent());    dataSource.setPassword(ele.getElementsByTagName("password").item(0).getTextContent());    dataSource.setUrl(ele.getElementsByTagName("jdbc-url").item(0).getTextContent());    dataSource.setInitialSize(5);    dataSource.setMinIdle(1);    dataSource.setMaxActive(10);// 启用监控统计功能    dataSource.setFilters("stat");//设置是否显示sql语句    targetDataSources.put(ele.getElementsByTagName("databasename").item(0).getTextContent(), dataSource);   }   return targetDataSources;  }  catch (Exception ex)  {   return null;  }  } //访问的ip @Value("${druid.IP}") private String IP; //登录名 @Value("${druid.druidLgoinName}") private String druidLgoinName; //密码 @Value("${druid.druidLgoinPassword}") private String druidLgoinPassword;  @Bean public ServletRegistrationBean DruidStatViewServle() {  //org.springframework.boot.context.embedded.ServletRegistrationBean提供类的进行注册.  ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");  //添加初始化参数：initParams   //白名单：  servletRegistrationBean.addInitParameter("allow",IP);  //IP黑名单 (存在共同时，deny优先于allow) : 如果满足deny的话提示:Sorry, you are not permitted to view this page.  // servletRegistrationBean.addInitParameter("deny", "192.168.1.73");  //登录查看信息的账号密码.  servletRegistrationBean.addInitParameter("loginUsername",druidLgoinName);  servletRegistrationBean.addInitParameter("loginPassword",druidLgoinPassword);  //是否能够重置数据.  servletRegistrationBean.addInitParameter("resetEnable","false");  return servletRegistrationBean; }  /**   * 注册一个：filterRegistrationBean   * @return  */ @Bean public FilterRegistrationBean druidStatFilter2(){  FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());  //添加过滤规则.  filterRegistrationBean.addUrlPatterns("/*");  //添加不需要忽略的格式信息.  filterRegistrationBean.addInitParameter("exclusions","*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");  return filterRegistrationBean; } }

public class DynamicDataSource extends AbstractRoutingDataSource{ //数据源路由，此方用于产生要选取的数据源逻辑名称 @Override protected Object determineCurrentLookupKey() {  //从共享线程中获取数据源名称  return DynamicDataSourceHolder.getDataSource(); }}public class DynamicDataSourceHolder { /**  * 本地线程共享对象  */ private static final ThreadLocal<String> THREAD_LOCAL = new ThreadLocal<>();  public static void putDataSource(String name) {  THREAD_LOCAL.set(name); }  public static String getDataSource() {  return THREAD_LOCAL.get(); }  public static void removeDataSource() {  THREAD_LOCAL.remove(); }}

@Component@Aspectpublic class DataSourceAspect { //切换放在mapper接口的方法上，所以这里要配置AOP切面的切入点 @Pointcut("execution( * com.example.demo.dao.*.*(..))") public void dataSourcePointCut() { }  @Before("dataSourcePointCut()") public void before(JoinPoint joinPoint) {  Object target = joinPoint.getTarget();  String method = joinPoint.getSignature().getName();  Class<?>[] clazz = target.getClass().getInterfaces();  Class<?>[] parameterTypes = ((MethodSignature) joinPoint.getSignature()).getMethod().getParameterTypes();  try {   Method m = clazz[0].getMethod(method, parameterTypes);   //如果方法上存在切换数据源的注解，则根据注解内容进行数据源切换   if (m != null && m.isAnnotationPresent(TargetDataSource.class)) {    TargetDataSource data = m.getAnnotation(TargetDataSource.class);    String dataSourceName = data.value();    DynamicDataSourceHolder.putDataSource(dataSourceName);    } else {    }  } catch (Exception e) {   } }  //执行完切面后，将线程共享中的数据源名称清空 @After("dataSourcePointCut()") public void after(JoinPoint joinPoint){  DynamicDataSourceHolder.removeDataSource(); }}