Spring AOP 运用

基于Spring 的 AOP  MethodBeforeAdvice 拦截增强 实现

方法执行前通知（可以理解为方法执行前“增强”）需要实现接口：MethodBeforeAdvice

AOP拦截实现类：
public class BaseModelBeforeAdvice implements MethodBeforeAdvice {

    private static Method addMethod = null;

    private static Method updateMethod = null;

    private static Method updateBatch = null;

    private static Logger logger = LoggerFactory.getLogger(BaseModelBeforeAdvice.class);

    public BaseModelBeforeAdvice() {
        try {
            addMethod = BaseDao.class.getMethod("add", Object.class);
            updateMethod = BaseDao.class.getMethod("update", Object.class);
            updateBatch = BaseDao.class.getMethod("updateBatch", Object.class, List.class);
        } catch (SecurityException e) {
            logger.error("初始化BaseModelBeforeAdvice class 安全错误", e);
        } catch (NoSuchMethodException e) {
            logger.error("初始化BaseModelBeforeAdvice class 没有找到方法错误", e);
        }
    }

    @Override
    public void before(Method method, Object[] args, Object target) throws Throwable {
        //添加方法
        if (method.equals(addMethod)) {
            if (BaseModel.class.isAssignableFrom(args[0].getClass())) {
                BaseModel baseModel = (BaseModel) args[0];
                //如果id为空才自动生成,不推荐在业务代码中直接设置id,临时方案应急使用 切记切记切记!!!
                if (StringUtil.isEmpty(baseModel.getId())) {
                    baseModel.setId(IDGenerate.uuid());
                }
                Date date = new Date(SystemClock.now());
                baseModel.setCreateDate(date);
                baseModel.setUpdateDate(date);
                //set当前用户操作信息
                try {
                    BaseUser baseUser = (BaseUser) SecurityUtils.getSubject().getPrincipal();
                    if (baseUser != null) {
                        baseModel.setCreateBy(baseUser.getId());
                        baseModel.setCreateByName(baseUser.getUsername());
                    }
                } catch (UnavailableSecurityManagerException e) {
                    logger.warn(" shiro security init fail " + e.getMessage());
                }
            } else if (BaseIncrementIdModel.class.isAssignableFrom(args[0].getClass())) {
                //如果是直接继承BaseIncrementIdModel类只需要这只id属性
                BaseIncrementIdModel baseIn = (BaseIncrementIdModel) args[0];
                baseIn.setId(IDGenerate.uuid());
            }
            if (Deleted.class.isAssignableFrom(args[0].getClass())) {
                ((Deleted) args[0]).setDeleted(Deleted.DELETE_FALSE);
            }
        } else if (method.equals(updateMethod) || method.equals(updateBatch)) {
            //修改方法
            if (BaseModel.class.isAssignableFrom(args[0].getClass())) {
                BaseModel baseModel = (BaseModel) args[0];
                baseModel.setUpdateDate(new Date(SystemClock.now()));
            }
        }
    }
}

Spring.xml文件增加面向切边 aop:config配置
<!-- baseDao方法拦截器，设置操作人和时间 -->
<bean id="baseModelBeforeAdvice" class="com.global.pdp.core.spring.BaseModelBeforeAdvice"/>
<aop:config>
        <aop:pointcut id="baseModelBeforeAdvicePoint"
                      expression="execution(* com.global.pdp.core.BaseDao.add(..)) or execution(* com.global.pdp.core.BaseDao.update(..)) or execution(* com.global.pdp.core.BaseDao.updateBatch(..))"/>
<aop:advisor advice-ref="baseModelBeforeAdvice" pointcut-ref="baseModelBeforeAdvicePoint"/>
</aop:config>