https://www.heckjj.com/index.php zh-cn https://www.heckjj.com/filter-locale-httpservletrequest/ Heck <@hecks.tk> Mon, 20 Sep 2010 18:22:33 +0000 https://www.heckjj.com/filter-locale-httpservletrequest/ 我们在HttpServletRequest中我们可以通过getLocale()得到用户请求的locale，但是如果你希望手动改变用户的locale设置的话却没有setLocale方法，那么有什么办法来改变request的locale设置吗呢？

答案是可以写一个HttpServletRequestWrapper，通过其中的getLocale()方法和getLocales()方法来改变用户请求的locale设置。首先我们来写一个这样的类：
public class LocaleRequestWrapper extends /** * http://www.hecks.tk/filter-locale-httpservletrequest/ */ HttpServletRequestWrapper {     public LocaleRequestWrapper(HttpServletRequest req) {       super(req);     }     public Enumeration getLocales() {       Vector v = new Vector(1);       v.add(getLocale());       return v.elements();     }     public Locale getLocale() {       String localeStr = getRequest().getParameter("locale");              Locale locale =  new Locale(localeStr);       return locale;     }   }
我们可以看到在getLocale()方法中我们得到request参数中的locale的值（想想用户请求的地址是http://www.hecks.tk?locale=zh_CN）。之后我们需要写一个filter，并使用LocaleRequestWrapper：
/** * http://www.hecks.tk/filter-locale-httpservletrequest/ */ public class LocaleFilter implements Filter {      public void doFilter(ServletRequest request, ServletResponse response,       FilterChain chain) throws IOException, ServletException {      if (request instanceof HttpServletRequest && request.getParameter("locale") != null) {               HttpServletRequest req = (HttpServletRequest)request;               LocaleRequestWrapper wrapper =                   new LocaleRequestWrapper(req);               chain.doFilter(wrapper, response);           } else {               chain.doFilter(request, response);           }   } }
可以看到，在其中的doFilter()方法中，如果请求的参数中含有locale的值，那么我们就会使用这个刚才设定的LocaleRequestWrapper。

写好Java代码之后，为了让我们的Filter能够生效，还需要在web.xml中配置对应的filter和filter-mapping：
<?xml version = "1.0"?> <web-app> <!-- Define the filters within the Web Application http://www.hecks.tk/filter-locale-httpservletrequest/ -->   <filter>     <filter-name>       ondev.net locale filter     </filter-name>     <filter-class>       net.ondev.demo.LocaleFilter     </filter-class>   </filter>   <!-- Map the filter to a Servlet or URL -->   <filter-mapping>     <filter-name>       ondev.net locale filter     </filter-name>     <url-pattern>       /*     </url-pattern>   </filter-mapping> </web-app>
Tags - filter , locale , httpservletrequest ]]> https://www.heckjj.com/filter-locale-httpservletrequest/#blogcomment <user@domain.com> Thu, 01 Jan 1970 00:00:00 +0000 https://www.heckjj.com/filter-locale-httpservletrequest/#blogcomment