Spring Filter过滤器,Spring拦截未登录用户权限限制

实现的功能：判断用户是否已登录，未登录用户禁止访问任何页面或action，自动跳转到登录页面。

比较好的做法是不管什么人都不能直接访问jsp页面，要访问就通过action，这样就变成了一个实实在在的权限控制了。

那么就有3种方法可以解决楼主的问题

1，直接使用filter

2，直接使用webwork的interceptor，

3，将action交给spring管理，使用spring的Aop机制

让用户可以直接访问jsp本来就违反了mvc的本意了

1 直接使用filter

web.xml配置

<filter>

<filter-name>SecurityServlet</filter-name>

<filter-class>com.*.web.servlet.SecurityServlet</filter-class>

</filter>

<filter-mapping>

<filter-name>SecurityServlet</filter-name>

<url-pattern>*.jsp</url-pattern>

</filter-mapping>

<filter-mapping>

<filter-name>SecurityServlet</filter-name>

<url-pattern>*.do</url-pattern>

</filter-mapping>

SecurityServlet 类

package com.*.web.servlet;

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.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

public class SecurityServlet extends HttpServlet implements Filter {

private static final long serialVersionUID = 1L;

public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException, ServletException {

HttpServletRequest request=(HttpServletRequest)arg0;

HttpServletResponse response =(HttpServletResponse) arg1;

HttpSession session = request.getSession(true);

String usercode = (String) request.getRemoteUser();// 登录人

String user_role = (String)session.getAttribute("role");//登录人角色

String url=request.getRequestURI();

if(usercode==null || "".equals(usercode) || user_role == null || "".equals(user_role)) {

//判断获取的路径不为空且不是访问登录页面或执行登录操作时跳转

if(url!=null && !url.equals("") && ( url.indexOf("Login")<0 && url.indexOf("login")<0 )) {

response.sendRedirect(request.getContextPath() + "/login.jsp");

return ;

}

}

arg2.doFilter(arg0, arg1);

return;

}

public void init(FilterConfig arg0) throws ServletException {

}

}

注意：

if(url!=null && !url.equals("") && ( url.indexOf("Login")<0 && url.indexOf("login")<0 )的问题，登录界面不要为index.jsp。即使你把if语句中的login改为index，过滤器会一直的index.jsp页面来跳转。所以登录界面不能为index.jsp

配置中的filter-mapping，定义的是需过滤的请求类型，上面的配置即过滤所有对jsp页面和action的请求。过滤器的实现与struts2、spring框架无关，在用户请求被相应前执行，在过滤器中，可使用response.sendRedirect("")等方法

跳转到需要的链接，如登录页面、错误页面等，不需要跳转时，arg2.doFilter(arg0, arg1);即可继续执行用户的请求。注意使用filter时避免连续两次跳转，否则会报java.lang.IllegalStateException错误，具体配置方法网上有，除非必要，不建议使用/*(过滤所有访问)的配置方式，这样配置，图片、js文件、css文件等访问都会被过滤

2 Spring拦截

Spring配置

<bean id="springSessionInterceptor" class="com.*.web.servlet.SpringLoginInterceptor" >

</bean>

<bean id="autoPorxyFactoryBean1"

class="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator">

<property name="interceptorNames">

<list>

<value>springLoginInterceptor</value>

</list>

</property>

<property name="beanNames" >

<list>

<value>*Controller</value>

</list>

</property>

</bean>

SpringLoginInterceptor实现类

package com.web.servlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import org.aopalliance.intercept.MethodInterceptor;

import org.aopalliance.intercept.MethodInvocation;

import org.apache.log4j.Logger;

import org.apache.struts.action.ActionMapping;

public class SpringLoginInterceptor implements MethodInterceptor {

private static final Logger log = Logger

.getLogger(SpringLoginInterceptor .class);

@Override

public Object invoke(MethodInvocation invocation) throws Throwable {

log.info("拦截开始！");

Object[] args = invocation.getArguments();

HttpServletRequest request = null;

HttpServletResponse response = null;

ActionMapping mapping = null;

for (int i = 0 ; i < args.length ; i++ ) {

if (args[i] instanceof HttpServletRequest) request = (HttpServletRequest)args[i];

if (args[i] instanceof HttpServletResponse) response = (HttpServletResponse)args[i];

if (args[i] instanceof ActionMapping) mapping = (ActionMapping)args[i];

}

if (request != null && mapping != null) {

String url=request.getRequestURI();

HttpSession session = request.getSession(true);

String usercode = (String) request.getRemoteUser();// 登录人

String user_role = (String)session.getAttribute("user_role");//登录人角色

if (usercode == null || usercode.equals("")) {

if ( url.indexOf("Login")<0 && url.indexOf("login")<0 ) {

return mapping.findForward("loginInterceptor");

}

return invocation.proceed();

}

else {

return invocation.proceed();

}

}

else {

return invocation.proceed();

}

}

}

//================================================================

在 SPRING 3 MVC 模式下，还可以如下实现：

import Javax.servlet.http.HttpServletRequest;
import Javax.servlet.http.HttpServletResponse;
public interface HandlerInterceptor {
// preHandle()方法在业务处理器处理请求之前被调用
boolean preHandle(HttpServletRequest request,
HttpServletResponse response,
Object handler)
throws Exception;
// postHandle()方法在业务处理器处理请求之后被调用
void postHandle(
HttpServletRequest request, HttpServletResponse
response, Object
handler, ModelAndView modelAndView)
throws Exception;
// afterCompletion()方法在DispatcherServlet完全处理完请求后被调用
void afterCompletion(
HttpServletRequest request, HttpServletResponse
response, Object
handler, Exception ex)
throws Exception;

}

public class SecurityFilter extends HandlerInterceptorAdapter {

@Override

public boolean preHandle(HttpServletRequest request,

HttpServletResponse response, Object handler) throws Exception {

System.out.println("==>>Begin to Filter session====");

HttpSession session = request.getSession();

String user = (String) session.getAttribute("user");

System.out.println("===??Current User=="+user);

String curPath=request.getRequestURL().toString();

System.out.println("===>> curpath:"+curPath);

if (curPath.indexOf("GPS/User/Index")>=0){

return true;

}

if(null==user || "".equals(user)){

return true;

/**

* handle session and security if you want.

*/

//request.getRequestDispatcher("/index.jsp").forward(request, response);

}

return super.preHandle(request, response, handler);

}

}

在 name-servlet.xml spring 的配置文件中注明：

<bean id="urlMapping" class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" >

<property name="interceptors">

<list>

<bean class="com.ibm.tds.filter.SecurityFilter"/>

</list>

</property>

</bean>

就可以用了。

近在研究struts，把以前做项目时候用拦截器实现的一些功能回想起来跟大家分享一下：

先创建一个拦截器，实现MethodFilterInterceptor这个抽象类，可以进行方法的限制和包含过滤。

该拦截器实现未登录不能进行访问的功能，可以扩展成对权限进行控制。

package com.struts2.interceptor;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.apache.struts2.ServletActionContext;

import org.apache.struts2.StrutsStatics;

import com.opensymphony.xwork2.ActionContext;

import com.opensymphony.xwork2.ActionInvocation;

import com.opensymphony.xwork2.interceptor.MethodFilterInterceptor;

public class LoginInterceptor extends MethodFilterInterceptor {

@Override

protected String doIntercept(ActionInvocation invocation) throws Exception {

// TODO Auto-generated method stub

ActionContext context = invocation.getInvocationContext();

//通过ActionContext来获取httpRequest

HttpServletRequest request = (HttpServletRequest)context.get(StrutsStatics.HTTP_REQUEST);

//也可以通过ServletActionContext来获取httpRequest

//HttpServletRequest request = ServletActionContext.getRequest();

//取得根目录的绝对路径

String currentURL = request.getRequestURI();

//截取到访问的相对路径，可以通过这个和权限表比较来进行相应的权限控制

String targetURL = currentURL.substring(currentURL.indexOf("/", 1), currentURL.length());

System.out.println(currentURL+".............."+targetURL);



//通过ActionContext获取session的信息，以Map形式返回

Map session = context.getSession();

//获取容器里面的username值，如果存在说明该用户已经登录，让他执行操作，如果未登录让他进行登录

String username = (String)session.get("username");

if(username!=null){

invocation.invoke();

}

context.put("nologin", "对不起，你没有登录，不能进行该操作");

return "login";

}

}

然后将这个拦截器配置的struts.xml里面：

<!-- 配置拦截器 -->

<package name="my-default" extends="struts-default">

<interceptors>

<!-- 配置未登录进行操作的拦截器 -->

<interceptor name="loginInterceptor" class="com.struts2.interceptor.LoginInterceptor">

<param name="param">测试参数</param>

</interceptor>

<!-- 重新封装一个默认的拦截器栈 -->

<interceptor-stack name="myDefaultStack">

<interceptor-ref name="loginInterceptor" />

<interceptor-ref name="defaultStack" />

</interceptor-stack>

</interceptors>

<!-- 为这个包设置默认的拦截器栈 -->

<default-interceptor-ref name="myDefaultStack" />

<!-- 设置全局的返回值 -->

<global-results>

<result name="login">/login.jsp</result>

</global-results>

</package>