切面+自定义注解的使用

1.applicationContext.xml中开启注解扫描

<context:component-scan base-package="com.lcb,com.lcb.soa.store.item" />

2.自定义注解

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
public @interface DateBaseName {

    String dataBaseName() default "";
}

3.定义切面类

/**
 * @author caiyike
 * @version 1.0
 * @date 2019-02-26 15:26
 */
@Aspect
@Component
public class DataBaseManager {

    @Pointcut("execution(* com.lcb.soa.store.item.test..*.*(..)) ")
    private void useDateBaseByName() {
    }


    @Around("useDateBaseByName()")
    public Object useMaster(ProceedingJoinPoint joinPoint) throws Throwable {
        Object[] args = joinPoint.getArgs();
        Method method = getMethod(joinPoint, args);
        //获取数据库名称参数
        String oldDataSource = DataSourceContextHolder.getRuntimeDataSourceKey();
        DateBaseName chooseDataSource = method.getAnnotation(DateBaseName.class);
        if(chooseDataSource != null){
            String dataBaseName = chooseDataSource.dataBaseName();
            DataSourceContextHolder.setDataSourceKey(dataBaseName);
            try {
                Object proceed = joinPoint.proceed();
                DataSourceContextHolder.setDataSourceKey(oldDataSource);
                return proceed;
            } catch (Throwable e) {
                throw e;
            } finally {
                DataSourceContextHolder.clearDataSourceKey();
            }
        }else {
            Object proceed = joinPoint.proceed();
            DataSourceContextHolder.setDataSourceKey(oldDataSource);
            return proceed;
        }

    }

    private Method getMethod(ProceedingJoinPoint joinPoint, Object[] args) throws NoSuchMethodException {
        String methodName = joinPoint.getSignature().getName();
        Class clazz = joinPoint.getTarget().getClass();
        Method[] methods = clazz.getMethods();
        for (Method method : methods) {
            if (methodName.equals(method.getName())) {
                return method;
            }
        }
        return null;
    }
}

4.Method上使用自定义注解

@DateBaseName(dataBaseName = "masterStoreItem")
public void method(){}

AOP中pointcut expression表达式参考

https://blog.csdn.net/kkdelta/article/details/7441829