使用web.xml在Tomcat 8上设置自定义筛选器

Question

我想使用这种方法（自定义过滤器） Tomcat CORS过滤器启用CORS Tomcat 8

我对在web.xml中调用自定义过滤器的步骤感到困惑。

如何设置.java文件？ 这个文件的目录在哪里（SimpleCORSFilter）？

public class SimpleCORSFilter implements Filter {

  public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
      HttpServletResponse response = (HttpServletResponse) res;
      response.setHeader("Access-Control-Allow-Origin", "*");
      response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
      response.setHeader("Access-Control-Max-Age", "3600");
      response.setHeader("Access-Control-Allow-Headers", "x-requested-with");
      chain.doFilter(req, res);
  }
}

Answer 1

将过滤器定义为连接到URL的示例 ：

 <filter> <filter-name>cors</filter-name> <filter-class>com.robin.filters.SimpleCORSFilter</filter-class> </filter> <filter-mapping> <filter-name>cors</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> 

将过滤器定义为连接到servlet的示例 ：

 <filter> <filter-name>MyFilter</filter-name> <display-name>MyFilter</display-name> <filter-class>com.xxx.yyy.zzz.MyFilter</filter-class> </filter> <filter-mapping> <filter-name>MyFilter</filter-name> <servlet-name>MyAction</servlet-name> </filter-mapping>