springboot项目设置过滤器拦截路由(filter登陆拦截)

ゝ一纸荒年。 2023-10-11 22:33 41阅读 0赞

**需求:登陆拦截，设置未登录不可直接通过url地址访问网站内部。**

1.给项目启动类加上注解 @ServletComponentScan //开启扫描配置的过滤器，监听器

@Slf4j
    @SpringBootApplication
    @ServletComponentScan //开启扫描配置的过滤器，监听器
    public class ReggieApplication {
        public static void main(String[] args) {
            SpringApplication.run(ReggieApplication.class);
            log.info("项目启动成功...");
        }
    }

2.新建filter包，登陆检查过滤器类 LoginCheckFilter类 ![e63c2ff26e1c476196feafeb61012fb4.png][]

3.编写过滤器代码

package cn.pjh.reggie.filter;
    
    import cn.pjh.reggie.common.R;
    import com.alibaba.fastjson.JSON;
    import lombok.extern.slf4j.Slf4j;
    import org.springframework.util.AntPathMatcher;
    import javax.servlet.*;
    import javax.servlet.annotation.WebFilter;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    
    /**
     * 检查用户是否完成登陆过滤器
     */
    @Slf4j
    @WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*")
    public class LoginCheckFilter implements Filter {
        //路由地址匹配器，用于检查是否包含我们设置的不需要过滤的路由
        public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();
    
        @Override
        public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
            HttpServletRequest request = (HttpServletRequest) servletRequest;
            HttpServletResponse response = (HttpServletResponse) servletResponse;
            //1.获取本次请求的uri
            String requestURI = request.getRequestURI();
            //定义不需要处理的url
            String[] urls = new String[]{
                    "/employee/login",
                    "/employee/logout",
                    "/backend/**",
                    "/front/**"
            };
            //2.判断本次请求是否需要处理
            boolean check = check(urls, requestURI);
            //3.如果不需要处理，直接放行
            if (check) {
                filterChain.doFilter(request, response);
                return;
            }
            //4.判断登陆状态，如果已经登陆，则直接放行
            if (request.getSession().getAttribute("employee") != null) {
                filterChain.doFilter(request, response);
                return;
            }
    
            //5.如果未登陆，通过输出流方式向客户端页面响应数据,路由跳转是前端设置拦截器通过后端返回固        
            //定的值前端拿到之后，在进行判断，最后进行页面跳转到
            response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        }
    
        //路由地址匹配器检查是否包含我们设置的不需要过滤的路由
    
        /**
         *
         * @param urls 不需要过滤的路由
         * @param requestUrl 本次请求的路由地址
         * @return
         */
        public boolean check(String[] urls, String requestUrl) {
            for (String url : urls) {
                if (PATH_MATCHER.match(url, requestUrl)) {
                    return true;
                }
            }
            return false;
        }
    
    }

返回值R是自定义的前后端交互的数据格式

package cn.pjh.reggie.common;
    
    import lombok.Data;
    import java.util.HashMap;
    import java.util.Map;
    
    @Data
    public class R<T> {
    
        private Integer code; //编码：1成功，0和其它数字为失败
    
        private String msg; //错误信息
    
        private T data; //数据
    
        private Map map = new HashMap(); //动态数据
    
        public static <T> R<T> success(T object) {
            R<T> r = new R<T>();
            r.data = object;
            r.code = 1;
            return r;
        }
    
        public static <T> R<T> error(String msg) {
            R r = new R();
            r.msg = msg;
            r.code = 0;
            return r;
        }
    
        public R<T> add(String key, Object value) {
            this.map.put(key, value);
            return this;
        }
    
    }

[e63c2ff26e1c476196feafeb61012fb4.png]: https://img-blog.csdnimg.cn/e63c2ff26e1c476196feafeb61012fb4.png