Servlet filter mapping exclude pattern

Once you apply a filter to a URL pattern:

<filter-mapping>
    <filter-name>theFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

there's no option in web.xml to exclude a more specific pattern such as: /public/*.

But you can put the exclusion logic in the filter itself:

<filter>
    <filter-name>theFilter</filter-name>
    <filter-class>org.demo.CustomServletFilter</filter-class>
    <init-param>
 <param-name>excludePatterns</param-name>
 <param-value>public/*</param-value>
    </init-param>
</filter>

And in the filter code:

public void init(FilterConfig cfg) throws ServletException {
 this.excludePatterns = cfg.getInitParameter("excludePatterns");
 .
 .
 .
}

public void doFilter(ServletRequest request,
           ServletResponse response,
    FilterChain chain) 
 throws IOException, ServletException {
 String url = request.getRequestURL().toString();
 if (matchExcludePatterns(url)) {
     chain.doFilter(request, response);
     return;
 }
 .
 .
 .
}