Question

我的应用程序中有2个过滤器。基于某些条件，我想选择是否执行第二个过滤器。有没有办法做到这一点？

我做了一些谷歌搜索没有成功。我希望请求继续而不执行第二个过滤器。这可能吗？

任何帮助将不胜感激。

Answer 1

除了科林的回答之外，还有另外一种方法：只是不要拨打FilterChain#doFilter()，而是RequestDispatcher#forward()。

if (condition) {
    request.getRequestDispatcher(((HttpServletRequest) request).getServletPath()).forward(request, response);
} else {
    chain.doFilter(request, response);
}

但是这会跳过当前开启的所有过滤器，期望正在收听<dispatcher>FORWARD</dispatcher>的过滤器。

Answer 2

您可以在请求中设置属性，并在第二个过滤器中进行检查。

public class FirstFilter implements Filter {
    //...

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        servletRequest.setAttribute("executeSecondFilter", true);
        //...
        if(someReason)
            servletRequest.setAttribute("executeSecondFilter", false);
        filterChain.doFilter(servletRequest, servletResponse);
    }
}

public class SecondFilter implements Filter {
    //..

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        if (servletRequest.getAttribute("executeSecondFilter") == null || !((Boolean) servletRequest.getAttribute("executeSecondFilter"))) {
            filterChain.doFilter(servletRequest, servletResponse);
        }
        //...
    }
}

您可以像这样简化上面的代码：

public class FirstFilter implements Filter {
    //...

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        //...
        if(someReason)
            servletRequest.setAttribute("executeSecondFilter", false);
        filterChain.doFilter(servletRequest, servletResponse);
    }
}

public class SecondFilter implements Filter {
    //..

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        if (servletRequest.getAttribute("executeSecondFilter") != null) {
            filterChain.doFilter(servletRequest, servletResponse);
        }
        //...
    }
}

这样您只需检查属性“executeSecondFilter”

的存在

如何在java中跳过过滤器链中的过滤器

2 个答案: