请教struts框架中连接postgresql数据库的问题
我想在struts框架中连接postgresql数据库，在网上找到了两种对数据源的配置，一种是：
struts-config.xml:

......
<data-sources>
<data-source key = "PostgresqlDB " type= "javax.sql.DataSource " 　factory= "org.apache.commons.dbcp.BasicDataSourceFactory ">
<set-property value= "true " property= "autoCommit "/>
<set-property value= "Example Data Source 　　　　　　　　　Configuration " property= "description "/>
<set-property value= "org.postgresql.Driver " property= "driverClass "/>
<set-property value= "5 " property= "maxCount "/>
<set-property value= "1 " property= "minCount "/>
<set-property value= "jdbc:postgresql://127.0.0.1:5432/postgres " property= "url "/>
<set-property value= "postgres " property= "user "/>
<set-property value= "postgres " property= "password "/>
</data-source>
</data-sources>
......


Action:
......
import javax.servlet.ServletContext;
......
ServletContext context = servlet.getServletContext();
DataSource dataSource = (DataSource) context.getAttribute( "PostgresqlDB ");
......

还有一种是:

struts-config.xml:

......
<data-sources>
<data-source>
<set-property property= "description " value= "Example Data Source Configuration "/>
<set-property property= "driverClass " value= "org.postgresql.Driver "/>
<set-property property= "maxCount " value= "4 "/>
<set-property property= "minCount " value= "2 "/>
<set-property property= "user " value= "postgres "/>
<set-property property= "password " value= "postgres "/>
<set-property property= "url " value= "jdbc:postgresql://localhost/postgres "/>
</data-source>
</data-sources>
......

Action:
......
DataSource dataSource = this.getDataSource(request);
......

不过都连不上DB,得到的dataSource是null.请问问题出在哪里呢？谢谢。

[解决办法]
有人知道吗……