web.xml文件
 
<servlet>
......
  <init-param> 
    <param-name>OracleDriver</param-name> 
    <param-value>oracle.jdbc.driver.OracleDriver</param-value> 
  </init-param> 
  <init-param> 
    <param-name>Address</param-name> 
    <param-value>localhost</param-value> 
  </init-param>
......
</servlet>
 
    重写init()方法，把读取web.xml的方法代码写在该方法里
 
@Override
public void init(ServletConfig _sysConfig) throws ServletException
{ 
    ConfigObj = OnloadConfig(_sysConfig);    
}

private WebConfig OnloadConfig(ServletConfig _sysConfig) throws ServletException,StringIndexOutOfBoundsException 
{ 
     ConfigObj.setDriveName(_sysConfig.getInitParameter("OracleDriver")); 
     ConfigObj.setAddress(sysConfig.getInitParameter("Address")); 
     return ConfigObj; 
}