第八篇：springboot filter配置

首先编写咱们本身的 filter

@WebFilter(urlPatterns = "/*")
public class MyFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("MyFilter..init..");
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.println("MyFilter..doFilter..");

        HttpServletRequest request= (HttpServletRequest) servletRequest;
        HttpServletResponse response= (HttpServletResponse) servletResponse;

        String URL=request.getRequestURI();
        if(URL.contains("upload")){
            response.sendRedirect("index.html");
            return;
        }else {
            filterChain.doFilter(servletRequest,servletResponse);
            return;
        }
    }

    @Override
    public void destroy() {
        System.out.println("MyFilter..destroy..");
    }
}

实现 Filter 接口，重写接口中的 init、doFilter、destory 方法

@WebFilter 标记一个类为filter，被spring进行扫描，urlPatterns：拦截规则，支持正则

在 doFilter 方法中编写自定义的逻辑，若是放行 则调用 doFilter（、、）方法

而后咱们须要配置自定义的 Filter ，之前是配置在 web.xml 中，如今咱们须要在 启动类中加入一行代码

@SpringBootApplication 
@ServletComponentScan 
public class DemoApplication {、、、、}

 

@ServletComponentScan  会扫描到咱们自定义的 filter