理解spring動態切換數據源，需要對spring具有一定的了解

工作中經常遇到讀寫分離，數據源切換的問題，那么以下是本作者實際工作中編寫的代碼 ?與大家分享一下！

??

1.定義注解?DataSource?

package com.gomecar.index.datasource;import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target;/*** 數據源切換注解* @author xiaotian**/ @Retention(RetentionPolicy.RUNTIME) @Target({ElementType.TYPE,ElementType.METHOD}) public @interface DataSource {String value() default "read";}

2. 定義切面DataSourceAspect

package com.gomecar.index.datasource;import java.lang.reflect.Method; import org.apache.log4j.Logger; import org.aspectj.lang.JoinPoint; import org.aspectj.lang.annotation.Aspect; import org.aspectj.lang.reflect.MethodSignature;/*** 用于數據庫讀寫分離的切面* @author xiaotian**/ @Aspect public class DataSourceAspect {//日志private Logger logger = Logger.getLogger(this.getClass());/*** 攔截目標方法，獲取由@DataSource指定的數據源標識，設置到線程存儲中以便切換數據源** @param point* @throws Exception*/public void intercept(JoinPoint point) throws Exception {Class<?> target = point.getTarget().getClass();MethodSignature signature = (MethodSignature) point.getSignature();for (Class<?> clazz : target.getInterfaces()) {resolveDataSource(clazz, signature.getMethod());}resolveDataSource(target, signature.getMethod());}/*** 提取目標對象方法注解和類型注解中的數據源標識** @param clazz* @param method*/private void resolveDataSource(Class<?> clazz, Method method) {try {Class<?>[] types = method.getParameterTypes();// 默認使用類型注解dataSourcePointcutdataSourcePointcutif (clazz.isAnnotationPresent(DataSource.class)) {DataSource source = clazz.getAnnotation(DataSource.class);DynamicDataSourceHolder.putDataSource(source.value());}// 方法注解可以覆蓋類型注解Method m = clazz.getMethod(method.getName(), types);if (m != null && m.isAnnotationPresent(DataSource.class)) {DataSource source = m.getAnnotation(DataSource.class);DynamicDataSourceHolder.putDataSource(source.value());}} catch (Exception e) {logger.error("切換數據源error", e);}}//通知public void before(JoinPoint point){Object target = point.getTarget();String method = point.getSignature().getName();//反射獲取接口Class<?>[] classz = target.getClass().getInterfaces();//獲取返回值類型 Class<?>[] parameterTypes = ((MethodSignature) point.getSignature()).getMethod().getParameterTypes();try {//獲取方法Method m = classz[0].getMethod(method, parameterTypes);//根據方法上注解 獲取只讀數據庫連接池 或者只寫數據庫連接池if (m != null && m.isAnnotationPresent(DataSource.class)) {//根據注解值獲取數據庫連接池DataSource data = m.getAnnotation(DataSource.class);DynamicDataSourceHolder.putDataSource(data.value());System.out.println(data.value());}} catch (Exception e) {// TODO: handle exception }} }

?

3.獲取動態數據源DynamicDataSource

package com.gomecar.index.datasource;import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource; /*** 動態獲取數據源* @author xiaotian**/ public class DynamicDataSource extends AbstractRoutingDataSource {@Overrideprotected Object determineCurrentLookupKey() {return DynamicDataSourceHolder.getDataSouce();}}

?

4.數據源持有者DynamicDataSourceHolder

package com.gomecar.index.datasource; /*** 數據庫連接池 持有者* 將數據庫連接綁定到當前線程* @author xiaotian**/ public class DynamicDataSourceHolder {//綁定當前線程public static final ThreadLocal<String> holder = new ThreadLocal<String>();//設置數據源public static void putDataSource(String name) {holder.set(name);}//獲取數據源public static String getDataSouce() {return holder.get();} }

?

轉載于:https://www.cnblogs.com/shoutn/p/7800916.html

總結

以上是生活随笔為你收集整理的spring 多数据源动态切换的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。