public StrutsXmlConfigurationProvider(boolean errorIfMissing) 
{
                           
        this("struts.xml", errorIfMissing, null);
}

Constructs the configuration provider

Parameters:

errorIfMissing - If we should throw an exception if the file can't be found

 public StrutsXmlConfigurationProvider(String filename,
    boolean errorIfMissing,
    ServletContext ctx) 
{
        super(filename, errorIfMissing);
        this.servletContext = ctx;
        this.filename = filename;
        reloadKey = "configurationReload-"+filename;
        Map< String,String > dtdMappings = new HashMap< String,String >(getDtdMappings());
        dtdMappings.put("-//Apache Software Foundation//DTD Struts Configuration 2.0//EN", "struts-2.0.dtd");
        setDtdMappings(dtdMappings);
        File file = new File(filename);
        if (file.getParent() != null) {
            this.baseDir = file.getParentFile();
        }
}

Constructs the configuration provider

Parameters:

filename - The filename to look for

errorIfMissing - If we should throw an exception if the file can't be found

ctx - Our ServletContext

 protected URL findInFileSystem(String fileName) throws IOException 
{
        URL url = null;
        File file = new File(fileName);
        if (LOG.isDebugEnabled()) {
            LOG.debug("Trying to load file " + file);
        }
        // Trying relative path to original file
        if (!file.exists()) {
            file = new File(baseDir, fileName);
        }
        if (file.exists()) {
            try {
                url = file.toURL();
            } catch (MalformedURLException e) {
                throw new IOException("Unable to convert "+file+" to a URL");
            }
        }
        return url;
}

 protected Iterator getConfigurationUrls(String fileName) throws IOException 
{
        URL url = null;
        if (baseDir != null) {
            url = findInFileSystem(fileName);
            if (url == null) {
                return super.getConfigurationUrls(fileName);
            }
        }
        if (url != null) {
            List< URL > list = new ArrayList< URL >();
            list.add(url);
            return list.iterator();
        } else {
            return super.getConfigurationUrls(fileName);
        }
}

Look for the configuration file on the classpath and in the file system

 public  void loadPackages() 
{
        ActionContext ctx = ActionContext.getContext();
        ctx.put(reloadKey, Boolean.TRUE);
        super.loadPackages();
}

 public boolean needsReload() 
{
        ActionContext ctx = ActionContext.getContext();
        return ctx.get(reloadKey) == null && super.needsReload();
}

Overrides needs reload to ensure it is only checked once per request

 public  void register(ContainerBuilder containerBuilder,
    LocatableProperties props) throws ConfigurationException 
{
        if (servletContext != null && !containerBuilder.contains(ServletContext.class)) {
            containerBuilder.factory(ServletContext.class, new Factory() {
                public Object create(Context context) throws Exception {
                    return servletContext;
                }
            });
        }
        super.register(containerBuilder, props);
}

 public String toString() 
{
        return ("Struts XML configuration provider ("+filename+")");
}