1. 数据源配置 spring.xml
2、配置数据源动态切面 spring.xml
3、配置数据库连接参数 jdbc.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/
jdbc.dbname1=family
jdbc.dbname2=employees
jdbc.params= useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true
jdbc.username=root
jdbc.password=123
#配置初始化大小、最小、最大
initialSize=0
maxActive=8
minIdle=0
maxIdle=8
#配置获取连接等待超时的时间
maxWait=20000
validationQuery=select 1
#打开PSCache，并且指定每个连接上PSCache的大小
poolPreparedStatements=true
maxPoolPreparedStatementPerConnectionSize=10
#配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
timeBetweenEvictionRunsMillis=60000
#配置一个连接在池中最小生存的时间，单位是毫秒
minEvictableIdleTimeMillis=1800000
4、定义一个类继承DynamicRoutingDataSource实现determineCurrentLookupKey方法，来实现数据库的动态切换
import org.apache.log4j.Logger;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
public class DynamicRoutingDataSource extends AbstractRoutingDataSource {
private static final Logger LOG=Logger.getLogger(DynamicRoutingDataSource.class);
@Override
protected Object determineCurrentLookupKey() {
LOG.info("当前数据源：{}"+DynamicDataSourceContextHolder.get());
return DynamicDataSourceContextHolder.get();
}
}
5、定义工具类DynamicDataSourceContextHolder ，用于动态切换数据源
import org.apache.log4j.Logger;
/**
* @ClassName DynamicDataSourceContextHolder
* @Description: TODO
* @Author Jason
* @Date 2020/3/18 12:15
* @Version V1.0
**/
public class DynamicDataSourceContextHolder {
private static final Logger LOG=Logger.getLogger(DynamicDataSourceContextHolder.class);
private static final ThreadLocal currenDataSource=new ThreadLocal<>();
/**
* @Author Jason
* @Description //清除当前数据源
* @Date 2020/3/18 12:19
* @Param
* @return
**/
public static void clear(){
currenDataSource.remove();
}
/**
* @Author Jason
* @Description //Description
* @Date 2020/3/18 20:50
* @Param []
* @return java.lang.String
**/
public static String get(){
return currenDataSource.get();
}
/**
* @Author Jason
* @Description 设置数据源
* @Date 2020/3/18 15:49
* @Param []
* @return void
**/
public static void setDataSource(String datasource) {
currenDataSource.set(datasource);
}
}
6、自定义注解@TargetDataSource，通过注解的值来获取当前数据源，并进行切换
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* @ClassName TargetDataSource
* @Description: 定义注解
* @Author Jason
* @Date 2020/3/18 17:07
* @Version V1.0
**/
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface TargetDataSource {
String value();
}
7、定义拦截器DynamicDataSourceInterceptor，解析注解切换数据源
import org.apache.log4j.Logger;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.reflect.MethodSignature;
import java.lang.reflect.Method;
/**
* @ClassName DynamicDataSourceInterceptor
* @Description: 数据源切换拦截器
* @Author Jason
* @Date 2020/3/18 17:32
* @Version V1.0
**/
public class DynamicDataSourceInterceptor {
private static final Logger LOG = Logger.getLogger(DynamicDataSourceInterceptor.class);
/**
* @Author Jason
* @Description 拦截目标方法，获取由@DataSource指定的数据源标识，设置到线程存储中以便切换数据源
* @Date 2020/3/18 17:39
* @Param [point]
* @return void
**/
public void intercept(JoinPoint point) throws Exception {
Class target = point.getTarget().getClass();
MethodSignature signature = (MethodSignature) point.getSignature();
resolveDataSource(target, signature.getMethod());
}
/**
* @Author Jason
* @Description 提取目标对象方法注解和类型注解中的数据源标识
* @Date 2020/3/18 17:40
* @Param [clazz, method]
* @return void
**/
private void resolveDataSource(Class clazz, Method method) {
try {
Class[] types = method.getParameterTypes();
// 默认使用类型注解
if (clazz.isAnnotationPresent(TargetDataSource.class)) {
TargetDataSource source = clazz.getAnnotation(TargetDataSource.class);
DynamicDataSourceContextHolder.setDataSource(source.value());
}
// 方法注解可以覆盖类型注解
Method m = clazz.getMethod(method.getName(), types);
if (m != null && m.isAnnotationPresent(TargetDataSource.class)) {
TargetDataSource source = m.getAnnotation(TargetDataSource.class);
DynamicDataSourceContextHolder.setDataSource(source.value());
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* @Author Jason
* @Description 执行方法后清除数据源设置
* @Date 2020/3/18 21:26
* @Param [joinPoint, targetDataSource]
* @return void
**/
public void afterIntercept(JoinPoint point) {
MethodSignature signature = (MethodSignature) point.getSignature();
Class[] types = signature.getParameterTypes();
Class target = point.getTarget().getClass();
try {
Method m = target.getMethod(signature.getName(), types);
if (m != null && m.isAnnotationPresent(TargetDataSource.class)) {
TargetDataSource source = m.getAnnotation(TargetDataSource.class);
LOG.info("当前数据源"+ source.value()+ "执行清理方法");
}
else{
LOG.info("当前数据源"+ DynamicDataSourceContextHolder.get()+ "执行清理方法");
}
}catch (Exception e) {
e.printStackTrace();
}
DynamicDataSourceContextHolder.clear();
}
}
8、@TargetDataSource注解实现数据源切换实例
import com.zqu.DataSource.TargetDataSource;
import com.zqu.bean.Employees;
import com.zqu.dao.IEmployeesDao;
import com.zqu.service.IEmployeesService;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;
import java.util.List;
/**
* @ClassName IEmployeesServiceImpl
* @Description: TODO
* @Author Jason
* @Date 2020/3/18 18:02
* @Version V1.0
**/
@Service("employeesService")
public class IEmployeesServiceImpl implements IEmployeesService {
@Resource(name="IEmployeesDao")
private IEmployeesDao eDao;
public List findDemo(){
return eDao.findDemo();
}
@TargetDataSource("dataSourceE")//切换数据源dataSourceE
public List find(){
return eDao.find();
}
}
[参考文章](https://blog.csdn.net/johnf_nash/article/details/63260561
)