key来自propertyies配置文件
index.title=MailReader Demonstration Application (Struts 1.1-dev)
<base href="http://localhost:8080/struts-example/">就来自于<html:base/>
index.title=MailReader Demonstration Application (Struts 1.1-dev)
<base href="http://localhost:8080/struts-example/">就来自于<html:base/>
他有一个属性index.title=MailReader Demonstration Application
propertyies文件在struts-config.xml中配置.