用Filter过滤的问题～！

Question

在用户登时，我想用Filter过滤jsp,.do,action文件有一个Filter
package demo.filter;import java.io.IOException;import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.*;public class LoginFilter implements Filter { public void init(FilterConfig config) throws ServletException {

}

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest)request;
HttpSession session = req.getSession();
if(session.getAttribute("name")!=null){
chain.doFilter(request, response);
}else{
request.getRequestDispatcher("login.jsp").forward(request, response);  
}
} public void destroy() {

}


}在web.xml中配置如下： <filter> 
<filter-name>loginFilter</filter-name>
<filter-class>demo.filter.LoginFilter</filter-class> 
</filter> 
<filter-mapping> 
<filter-name>loginFilter</filter-name> 
<url-pattern>*.jsp</url-pattern> 
</filter-mapping>
<filter-mapping> 
<filter-name>loginFilter</filter-name> 
<url-pattern>*.do</url-pattern> 
</filter-mapping>如果在用户登录则可以继续看后面页面．否则要跳转到login.jsp页面．可是我在未登陆时还是可以访问.do的，而不是转到 login.jsp页面．
request.getRequestDispatcher("login.jsp").forward(request, response);  这句话好象不起作用．
还有过滤*.jsp,*.do时，如果.do后面有参数，如：login.do?name=aaa&password=bbb，这样的形式，按照配置的过滤器，可以被过滤掉吗？

Answer 1

你配置了过滤*.jsp和*.do，当然login.jsp也被过滤了，从而不可到达login.jsp页面还有过滤*.jsp,*.do时，如果.do后面有参数，如：login.do?name=aaa&password=bbb，这样的形式，按照配置的过滤器，可以被过滤掉吗？可以被过滤

Answer 2

toPageURL = httpRequest.getContextPath() + toPage;
httpResponse.encodeRedirectURL(toPageURL);
httpResponse.sendRedirect(toPageURL);

Answer 3

    
package demo.filter;import java.io.IOException;import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.*;public class LoginFilter implements Filter {    public void init(FilterConfig config) throws ServletException {
    
    }
    
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        HttpServletResponse httpResponse = (HttpServletResponse) response;
        HttpSession session = req.getSession();
        if(session.getAttribute("name")!=null){
            chain.doFilter(request, response);
        }else{
            String toPageURL = httpRequest.getContextPath() + "login.jsp"; 
            httpResponse.encodeRedirectURL(toPageURL); 
            httpResponse.sendRedirect(toPageURL); 
        }
    }    public void destroy() {
        
    }
    
    
}

Answer 4

<filter> 
        <filter-name>loginFilter</filter-name>
        <filter-class>demo.filter.LoginFilter</filter-class> 
    </filter> 
    <filter-mapping> 
        <filter-name>loginFilter</filter-name> 
        <url-pattern>/*</url-pattern> 
    </filter-mapping>
    <filter-mapping>
全部过滤..

Answer 5

public class LoginFilter implements Filter {
    private FilterConfig _filterConfig = null;    public void init(FilterConfig filterConfig) throws ServletException {
        _filterConfig = filterConfig;
    }    public void destroy() {
        _filterConfig = null;
    }    public void doFilter(ServletRequest request, ServletResponse response, 
                         FilterChain chain) throws IOException, ServletException {
                         
                 HttpServletRequest req=(HttpServletRequest)request;
                 HttpServletResponse resp=(HttpServletResponse)response;
                 req.setCharacterEncoding("GBK");
                 if (req.getSession().isNew()){
                     resp.sendRedirect("login.htm");
                 }
                     chain.doFilter(request, response);
    }
}
我是这样做的,绝对成功

Answer 6

LoginFilterpublic class LoginFilter implements Filter {
   
public static boolean isContains(String container, String[] regx) {
        boolean result = false;        for (int i = 0; i < regx.length; i++) {
              if (container.indexOf(regx[i]) != -1) {
               result=true;
              }
        }
        return result;
  }  public FilterConfig config;  public void setFilterConfig(FilterConfig config) {
        this.config = config;
  }  public FilterConfig getFilterConfig() {
        return config;
  }  public void doFilter(ServletRequest request, ServletResponse response,
              FilterChain chain) throws IOException, ServletException {        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponseWrapper wrapper = new HttpServletResponseWrapper((HttpServletResponse) response);
        System.out.println(wrapper);
        String logonStrings = config.getInitParameter("logonStrings");//logonStrings，登陆页面
        String includeStrings = config.getInitParameter("includeStrings");//includeStrings，过滤页面参数
        String redirectPath = req.getContextPath()+ config.getInitParameter("redirectPath");//redirectPath，没有登陆转向页面
        String disabletestfilter = config.getInitParameter("disabletestfilter");//disabletestfilter，过滤器是否有效。        if (disabletestfilter.toUpperCase().equals("N")) {
              chain.doFilter(request, response);
              return;
        }
        String[] logonList = logonStrings.split(";");
        String[] includeList = includeStrings.split(";");
        Object userInfo =req.getSession().getAttribute("userInfo");
        Object isLogin = req.getSession().getAttribute("isLogin");
        System.out.println(userInfo);
        System.out.println(isLogin);
        if (userInfo== null||isLogin==null) {
              if (!LoginFilter.isContains(req.getRequestURI(),includeList)) {
                    chain.doFilter(request, response);
                    return;
              }
              if (LoginFilter.isContains(req.getRequestURI(),logonList)) {
                    chain.doFilter(request, response);
                    return;
              }
              wrapper.sendRedirect(redirectPath);
        } else {
              chain.doFilter(request, response);
        }
  }  public void destroy() {
        this.config = null;
  }  public void init(FilterConfig filterConfig) throws ServletException {
        this.config = filterConfig;
  }

        
}
web.xml<filter>
<filter-name>LoginFilter</filter-name>
<filter-class>com.exam.filter.LoginFilter</filter-class>
<init-param>
<param-name>logonStrings</param-name>
<param-value>/login.jsp</param-value>
</init-param>
<init-param>
<param-name>includeStrings</param-name>
<param-value>.jsp;</param-value>   //可以自己修改！
</init-param>
<init-param>
<param-name>redirectPath</param-name>
<param-value>/login.jsp</param-value>
</init-param>
<init-param>
<param-name>disabletestfilter</param-name>
<param-value>Y</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>LoginFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>