采用struts2 小伙伴非常希望更改或删除action扩展，本文将帮助你实现

struts2-core-2.3.16.jar ， 下载链接： http://repo1.maven.org/maven2/org/apache/struts/struts2-core/2.3.16/

org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter , 这个struts2处理请求的函数doFilter 。 在这里使用了 prepare.isUrlExcluded来推断是否排除的请求。假设是就直接运行chain.doFilter(request, response);交给其它的Filter处理，否则自己处理此action

//...  // protected PrepareOperations prepare;

    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) req;

        HttpServletResponse response = (HttpServletResponse) res;

        try {

            if (excludedPatterns != null && prepare.isUrlExcluded(request, excludedPatterns)) { //看这里

                chain.doFilter(request, response);

            } else {

                prepare.setEncodingAndLocale(request, response);

                prepare.createActionContext(request, response);

                prepare.assignDispatcherToThread();

                request = prepare.wrapRequest(request);

                ActionMapping mapping = prepare.findActionMapping(request, response, true);

                if (mapping == null) {

                    boolean handled = execute.executeStaticResourceRequest(request, response);

                    if (!handled) {

                        chain.doFilter(request, response);

                    }

                } else {

                    execute.executeAction(request, response, mapping);

                }

            }

        } finally {

            prepare.cleanupRequest(request);

        }

    }

//...

org.apache.struts2.dispatcher.ng.PrepareOperations

/**

     * Check whether the request matches a list of exclude patterns.

     *

     * @param request          The request to check patterns against

     * @param excludedPatterns list of patterns for exclusion

     *

     * @return <tt>true</tt> if the request URI matches one of the given patterns

     */

    public boolean isUrlExcluded( HttpServletRequest request, List<Pattern> excludedPatterns ) {

        if (excludedPatterns != null) {

            String uri = RequestUtils.getUri(request);

            for ( Pattern pattern : excludedPatterns ) {

                if (pattern.matcher(uri).matches()) {

                    return true;

                }

            }

        }

        return false;

    }

经过以上的分析。如今在看看struts2的默认配置文件default.properties，在struts2-core-2.3.16.jar，  org.apache.truts2以下

### Used by the DefaultActionMapper

### You may provide a comma separated list, e.g. struts.action.extension=action,jnlp,do

### The blank extension allows you to match directory listings as well as pure action names

### without interfering with static resources, which can be specified as an empty string

### prior to a comma e.g. struts.action.extension=, or struts.action.extension=x,y,z,,

struts.action.extension=action,,

依据描写叙述。能够设置struts.action.extension的value为一个逗号就能够支持无扩展名的action了。假设想兼容之前的，能够加入上之间的,如：  

<pre name="code" class="plain">struts.action.extension=<span style="font-family: Arial, Helvetica, sans-serif;">do,action,jspt,, </span>

另外。假设你使用的struts2的版本号低于2.3.16（至于详细那个版本号是过度的。我没有測试），静态资源js,css可能会被吃掉了，能够加入例如以下的一个属性

struts.action.excludePattern=/css,/javascript

有的项目中处理js和css的方式是对js、css进行压缩的servlet，如：

<link type="text/css" rel="stylesheet" href="/compressor?

v=${globalVersion}&type=css&munge=true&files=/cssStyle/index.css,/cssStyle/dialog.css,/cssStyle/jbox/Gray/jbox.css,/cssStyle/home.css">

<script src="/compressor?v=${globalVersion}&type=js&munge=true&files=

/javascript/lib/json2/json2.js,

/javascript/lib/jquery/1.7.2/jquery.js,

/javascript/lib/jquery/jquery.ext.js,

/javascript/lib/juicer/0.6.1/juicer-min.js,

/javascript/lib/underscore/1.3.3/underscore-min.js,

/javascript/lib/cookie/cookie.min.js,

/javascript/core/core.js,

/javascript/core/toptips.js,

/javascript/core/selectBankCard.js,

/javascript/core/dialog.js,

/javascript/core/page.js,

/javascript/core/regex.js,

/javascript/core/topLogRegister.js"

type="text/javascript"></script>

即使用servlet  compressor 输出js和css文件，此时配置应例如以下

struts.action.excludePattern=/compressor

如要过滤 以 “/druid”和“/compressor”开头的请求，模式例如以下(注意加入的是".*"。而不仅仅是“*”)

struts.action.excludePattern=/compressor.*,/druid.*

注意：在设置struts2的配置时。最好使用struts.properties，由于我在struts.xml中使用同样的配置，就不兼容曾经的".do"了。假设struts.properties和struts.xml同一时候存在，struts.properties的优先级会高于struts.xml