Filter来控制权限

文章出自：http://neil-jh.javaeye.com/blog/191341

目前很多项目对权限的控制一般普遍使用Acgi来控制权限。这里对老技术做一个回顾，曾经使用过Filter来控制权限，如果对Filter不是很熟悉的朋友，可以简单看下，也许多少会有些帮助。

public class PopedomFilter implements Filter {    public void init(FilterConfig filterConfig) throws ServletException {

    }

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {        HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;        HttpServletResponse httpServletResponse = (HttpServletResponse) servletResponse;

        String contextPath = httpServletRequest.getContextPath();   //取得项目当前根目录   例如：/project        String currentPath = httpServletRequest.getRequestURI();    //取得当前要访问的页面目录   /project/admin/xxx.action

        if (!checkUserPopedom(httpServletRequest, httpServletResponse, contextPath, currentPath)) {     //检查当前访问的路径是否包含在此用户的权限列表中，如果不存在return出去，不进行下一步的调用            return;        }

        filterChain.doFilter(servletRequest, servletResponse);

    }

    private boolean checkUserPopedom(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, String contextPath, String currentPath) throws IOException {        User user = (User) httpServletRequest.getSession(true).getAttribute("user");

        if (user == null) {            httpServletResponse.sendRedirect(contextPath + "/");            return false;        } else {            if (!checkPopedom(user, contextPath, currentPath)) {                httpServletResponse.sendRedirect(contextPath + "/");                return false;            }        }

        return true;    }

    private boolean checkPopedom(User user, String contextPath, String currentPath) {        if (user.getSystemResourceList() != null) {            for (SystemResource resource : user.getSystemResourceList()) {                String url = contextPath + resource.getActionUrl().trim();                if (url.equals(currentPath)) {                    return true;                }            }        }        return false;    }

    public void destroy() {    }}

 

在web.xml 中需要对这个Filter进行配置如下

<filter>     <filter-name>PopedomFilter </filter-name>     <filter-class>...filter.RightFilter</filter-class> </filter>

<filter-mapping>     <filter-name>PopedomFilter </filter-name>     <url-pattern>*.action</url-pattern>

 </filter-mapping>