Shareach

好久没写过前端代码了，昨天和前端大师讨论HTML5效果，心血来潮，发现css3确实好用，做了个css3效果替代图片，后面继续测试各种效果，http://www.shareach.com/css3/corner.html,

1.Auto-Sharding方式社区里面说不好否定了，Replica Sets在自动选举时候有点慢；所以采用master-slave结构；

2.碎片整理和数据文件收缩是噩梦，磁盘空间无限加大；

3.复杂查询的分页问题；

4.最关键的原因：身边还没有10000w级数据实际生产环境的例子；

还没深入太多，可能不是很熟悉的原因；所以暂时还是求稳用mysql比较靠谱，mongodb只用做 GridFS和日志文件存储

好多年没动过J2ee了，搞了2个晚上终于整出了全套3.0的VSSI框架, 后面继续CodeSmith模版，写完了还没测试，全部代码和Eclipse项目压缩文件下载

参考资料 http://code.google.com/p/mybatis/wiki/Spring

mysql 数据库，用了 JPetShop的Item表，表结构是：
CREATE TABLE `item` (                                 
         `itemid` varchar(10) collate utf8_bin NOT NULL,     
         `productid` varchar(10) collate utf8_bin NOT NULL,  
         `listprice` decimal(10,2) default NULL,             
         `unitcost` decimal(10,2) default NULL,              
         `supplier` int(11) default NULL,                    
         `status` varchar(2) collate utf8_bin default NULL,  
         `attr1` varchar(80) collate utf8_bin default NULL,  
         `attr2` varchar(80) collate utf8_bin default NULL,  
         `attr3` varchar(80) collate utf8_bin default NULL,  
         `attr4` varchar(80) collate utf8_bin default NULL,  
         `attr5` varchar(80) collate utf8_bin default NULL,  
         PRIMARY KEY  (`itemid`),                            
         KEY `fk_item_2` (`supplier`),                       
         KEY `itemProd` (`productid`)                        
       ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin 

表数据：
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-1','FI-SW-01','16.50','10.00','1','P','Large',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-2','FI-SW-01','16.50','10.00','1','P','Small',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-3','FI-SW-02','18.50','12.00','1','P','Toothless',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-4','FI-FW-01','18.50','12.00','1','P','Spotted',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-5','FI-FW-01','18.50','12.00','1','P','Spotless',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-6','K9-BD-01','18.50','12.00','1','P','Male Adult',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-7','K9-BD-01','18.50','12.00','1','P','Female Puppy',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-8','K9-PO-02','18.50','12.00','1','P','Male Puppy',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-9','K9-DL-01','18.50','12.00','1','P','Spotless Male Puppy',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-10','K9-DL-01','18.50','12.00','1','P','Spotted Adult Female',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-11','RP-SN-01','18.50','12.00','1','P','Venomless',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-12','RP-SN-01','18.50','12.00','1','P','Rattleless',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-13','RP-LI-02','18.50','12.00','1','P','Green Adult',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-14','FL-DSH-01','58.50','12.00','1','P','Tailless',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-15','FL-DSH-01','23.50','12.00','1','P','With tail',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-16','FL-DLH-02','93.50','12.00','1','P','Adult Female',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-17','FL-DLH-02','93.50','12.00','1','P','Adult Male',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-18','AV-CB-01','193.50','92.00','1','P','Adult Male',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-19','AV-SB-02','15.50','2.00','1','P','Adult Male',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-20','FI-FW-02','5.50','2.00','1','P','Adult Male',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-21','FI-FW-02','5.29','1.00','1','P','Adult Female',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-22','K9-RT-02','135.50','100.00','1','P','Adult Male',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-23','K9-RT-02','145.49','100.00','1','P','Adult Female',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-24','K9-RT-02','255.50','92.00','1','P','Adult Male',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-25','K9-RT-02','325.29','90.00','1','P','Adult Female',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-26','K9-CW-01','125.50','92.00','1','P','Adult Male',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-27','K9-CW-01','155.29','90.00','1','P','Adult Female',NULL,NULL,NULL,NULL);
insert into `item` (`itemid`, `productid`, `listprice`, `unitcost`, `supplier`, `status`, `attr1`, `attr2`, `attr3`, `attr4`, `attr5`) values('EST-28','K9-RT-01','155.29','90.00','1','P','Adult Female',NULL,NULL,NULL,NULL);

eclipse Indigo, JDK1.6, Tomcat 6 ，全部代码和Eclipse项目压缩文件下载

整体缓存主要嫁接在Memcached和Redis上，Memcached是原子性的Key-Value操作，Redis是借助于其Set、SortedSet的功能将列表置于Redis，提升整体系统性能。

启动2级缓存，写入缓存前，先本地暂存本地队列，再写入数据库，同时更新缓存，这样可以保持所有前端服务器同步；读取时，缓存都是LazyLoading，先读取缓存，如果缓存不存在再将数据库数据读取到缓存，这样加快系统初始化时间；缓存设置时间主动过期，而是当数据更新时候，才去更新缓存；这么做的缺点是，缓存容量要相当大；

缓存采用3层缓存结构，既数据持久层PO、业务逻辑层BO、表示层VO，每级缓存向下依赖

采用向下注册模式，既表示层层向BL层注册、BL向DAL注册，但是BL不必要关心VO具体怎么用，仅仅是为了，当BO被更新时候，知道清理那些VO，同理可证PO和BO关系；