p2p登录拦截

1.编写拦截标签

package com.xmg.p2p.base.util;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * 用来标记登陆的标签(登录拦截)
 * @author Administrator
 *
 */
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface RequireLogin {
    
}

2.在需要拦截的方法上写标签

@RequireLogin

3.专门用于登录检查的拦截器

package com.xmg.p2p.base.util;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
/**
 * 专门用于登录检查的拦截器
 * @author Administrator
 *
 */
public class LoginCheckInterceptor extends HandlerInterceptorAdapter {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {
        //判断登录逻辑
        //1.
        if (handler instanceof HandlerMethod) {
            HandlerMethod hm = (HandlerMethod) handler;
            RequireLogin rl = hm.getMethodAnnotation(RequireLogin.class);
            if (rl!=null && UserContext.getCurrent()==null) {
                response.sendRedirect("/login.html");
                return false;
            }
        }
        return super.preHandle(request, response, handler);
    }
}    

4.在springMvc中配置拦截器

 <!--   配置拦截器 -->
    <mvc:interceptors>
        <mvc:interceptor>
            <mvc:mapping path="/*"/>
            <bean class="com.xmg.p2p.base.util.LoginCheckInterceptor" />
        </mvc:interceptor>
    </mvc:interceptors>
    

（登录检查拦截器的用于存放当前用户的上下文UserContext）

package com.xmg.p2p.base.util;

import javax.servlet.http.HttpSession;

import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import com.xmg.p2p.base.domain.Logininfo;

/**
 * 用于存放当前用户的上下文
 * @author Administrator
 *
 */
public class UserContext {
    public static final String USER_IN_SESSION = "logininfo";
    
    /**
     * 方向获取request
     * @return
     */
    private static HttpSession getSesssion(){
        return ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest().getSession();
    }
    
    public static void putCurrent(Logininfo current){
        getSesssion().setAttribute(USER_IN_SESSION, current);;
    }
    public static Logininfo getCurrent(){
        
        return (Logininfo) getSesssion().getAttribute(USER_IN_SESSION);
    }
}