(1) 请求信息编码转化的Filter
importjava.io.IOException;
importjava.util.Enumeration;
importjavax.servlet.Filter;
importjavax.servlet.FilterChain;
importjavax.servlet.FilterConfig;
importjavax.servlet.ServletException;
importjavax.servlet.ServletRequest;
importjavax.servlet.ServletResponse;
public class EncodeFilter implementsFilter{
private FilterConfig filterConfig=null;
private String encoding=null;
//默认构造函数
public EncodeFilter(){
}
//初始化过滤器
public void init(FilterConfig filterConfig)throwsServletException{
this.filterConfig=filterConfig;
this.encoding=filterConfig.getInitParameter("encoding");
}
//得到编码
private String getEncoding(){
return this.encoding;
}
//执行过滤操作
public void doFilter(ServletRequestrequest,ServletResponseresponse,
FilterChainfilterChain)throws
IOException,ServletException{
//设置编码格式
if(request.getCharacterEncoding()==null){
//从配置文件得到编码
String encoding=getEncoding();
//设置编码
if(encoding!=null){
request.setCharacterEncoding(encoding);
}
//传递过滤器
filterChain.doFilter(request,response);
}
}
public void destroy(){
filterConfig=null;
encoding=null;
}
}
web.xml文件配置
<filter>
<filter-name>SetEncodingFilter</filter-name>
<filter-class>cn.mblogger.mydeman.EncodeFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>GBK</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>SetEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
(2) 检测用户是否登陆的过滤器
/**
用于检测用户是否登陆的过滤器，如果未登录，则重定向到指的登录页面
checkSessionKey �
