Java servlets和数据库连接池(Java servlets and database connection pooling)
仅查看Web上连接池的示例,它们都以每个小服务程序为基础实现连接池。 所以每个servlet都有自己的数据库连接池。 我的问题是,为什么更喜欢像db连接的全局池? 由于全局池似乎比每个servlet池更有效率..
另外,因为我正在考虑实施这样的游泳池。 有没有办法让一个类在servlets之前初始化(我使用jetty btw)? 我只是开始servlet开发,但对于配置等其他方面也很有用。 否则,我只是想使用某种类似单例模式..
Just looking at examples of connection pooling on the web, they all implement connection pooling on a per servlet basis. So each servlet has its own pool of database connections. My question is, why is that preferable to something like a global pool of db connections? Since a global pool is seems more efficient than a per servlet pool..
Also, since I'm thinking about implementing such a pool. Is there a way to have a class initialized before the servlets(I'm using jetty btw)? I'm just starting servlet development but that would seem useful for other things too like configuration. Otherwise I was just going to use some sort of singleton like pattern..
原文:https://stackoverflow.com/questions/1548249
最满意答案
用sed:
sed "s/^AIX$/& $(hostname)/" file
如果该行可以包含
AIX
:sed "s/AIX.*/& $(hostname)/" file
编辑:
要在匹配行后附加主机名,请尝试
a
(append)命令:sed "/^AIX$/a $(hostname)" file
With sed:
sed "s/^AIX$/& $(hostname)/" file
If the line could contain
AIX
:sed "s/AIX.*/& $(hostname)/" file
Edit:
To append the hostname after the matching line, try the
a
(append) command:sed "/^AIX$/a $(hostname)" file
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