PHP缓存文件（.htaccess）

I have the following code which I am using for my website. I would like to know if this code is correct in order for me to effectively cache me pages and files. I have tried to use tools to check this but some say they don't see that I am caching.

<ifModule mod_headers.c>
    # 1 Month
    <filesMatch ".(ico|gif|jpg|jpeg|png|pdf)$">
        Header set Cache-Control "max-age=2419200"
    </FilesMatch>

    # 1 Week
    <filesMatch ".(css|js)$">
        Header set Cache-Control "max-age=604800"
    </FilesMatch>

    # 1 Day
    <filesMatch ".(htm|html)$">
        Header set Cache-Control "max-age=86400"
    </FilesMatch>
</ifModule>

Catching is the automatic mechanism of the browsers. When a page is loading, browser checks the cache for static files like js, css, images..., if they are not available browser will pus them into cache.

To determine whether the file is cached or not, check the firebug console and clik on request link.

here you can see information like

    Accept-Ranges   bytes
    Cache-Control   max-age=290304000, public
    Content-Encoding    gzip
    Content-Length  2824
    Content-Type    application/javascript
    Date    Thu, 11 Jul 2013 10:15:06 GMT
    Expires Fri, 12 Jul 2013 10:15:06 GMT
    Last-Modified   Thu, 03 Jan 2013 16:05:54 GMT
    Server  Apache
    Vary    Accept-Encoding,User-Agent