Spring boot 过滤器

• 比如实现登录验证功能

在 Application 添加过滤器注解

@ServletComponentScan // 扫描过滤器
public class ActualprojectApplication {

    public static void main(String[] args) {
        SpringApplication.run(ActualprojectApplication.class, args);
    }

}

• 实现过滤器类

/*
 * 用户登录过滤器，检查用户是否登录
 */
@WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*") //检查所有接口是否登录
@Slf4j
public class LoginCheckFilter implements Filter {

    // 路径匹配器
    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;
        log.info("拦截的请求: " + request.getRequestURI());
        // 获取本次请求的URI
        String requestURI = request.getRequestURI();
        // 设置不需要处理的请求路径
        String[] urls = new String[] {
                "/employee/login",
                "/employee/loginout"
        };
        // 判断拦截的请求是否需要处理
        Boolean isHandle = this.checkURI(urls, requestURI);
        // 不需要处理直接放行
        if (isHandle) {
            filterChain.doFilter(servletRequest,servletResponse);
            return;
        }
        // 判断登录状态,如果登录直接放行
        if (request.getHeader("token") != null) {
            filterChain.doFilter(servletRequest,servletResponse);
            return;
        }
        // 如果未登录
        response.getWriter().write(JSON.toJSONString(Result.error("no login!")));
    }

    public Boolean checkURI(String[] urls,String requestUrl) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestUrl);
            if (match) {
                return true;
            }
        }
        return false;
    }
    
}