File	Doc	Category	Size	Date	Package
FilterDispatcher.java	API Doc	Example	21534	Mon Jul 23 13:26:38 BST 2007	org.apache.struts2.dispatcher

FilterDispatcher

• java.lang.Object

Fields Summary
private static final Log	LOG Provide a logging instance.
private String[]	pathPrefixes Store set of path prefixes to use with static resources.
private final Calendar	lastModifiedCal Provide a formatted date for setting heading information when caching static content.
private static boolean	serveStatic Store state of StrutsConstants.STRUTS_SERVE_STATIC_CONTENT setting.
private static boolean	serveStaticBrowserCache Store state of StrutsConstants.STRUTS_SERVE_STATIC_BROWSER_CACHE setting.
private static String	encoding Store state of StrutsConstants.STRUTS_I18N_ENCODING setting.
private static org.apache.struts2.dispatcher.mapper.ActionMapper	actionMapper Provide ActionMapper instance, set by injection.
private FilterConfig	filterConfig Provide FilterConfig instance, set on init.
protected Dispatcher	dispatcher Expose Dispatcher instance to subclass.

Constructors Summary

Methods Summary
protected void	copy(java.io.InputStream input, java.io.OutputStream output) Copy bytes from the input stream to the output stream. param input The input stream param output The output stream throws IOException If anything goes wrong final byte[] buffer = new byte[4096]; int n; while (-1 != (n = input.read(buffer))) { output.write(buffer, 0, n); } output.flush(); // WW-1526
protected Dispatcher	createDispatcher(javax.servlet.FilterConfig filterConfig) Create a default {@link Dispatcher} that subclasses can override with a custom Dispatcher, if needed. param filterConfig Our FilterConfig return Initialized Dispatcher Map<String,String> params = new HashMap<String,String>(); for (Enumeration e = filterConfig.getInitParameterNames(); e.hasMoreElements(); ) { String name = (String) e.nextElement(); String value = filterConfig.getInitParameter(name); params.put(name, value); } return new Dispatcher(filterConfig.getServletContext(), params);
public void	destroy() Calls dispatcher.cleanup, which in turn releases local threads and destroys any DispatchListeners. see javax.servlet.Filter#destroy() if (dispatcher == null) { LOG.warn("something is seriously wrong, Dispatcher is not initialized (null) "); } else { dispatcher.cleanup(); }
public void	doFilter(javax.servlet.ServletRequest req, javax.servlet.ServletResponse res, javax.servlet.FilterChain chain) Process an action or handle a request a static resource. The filter tries to match the request to an action mapping. If mapping is found, the action processes is delegated to the dispatcher's serviceAction method. If action processing fails, doFilter will try to create an error page via the dispatcher. Otherwise, if the request is for a static resource, the resource is copied directly to the response, with the appropriate caching headers set. If the request does not match an action mapping, or a static resource page, then it passes through. see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain) HttpServletRequest request = (HttpServletRequest) req; HttpServletResponse response = (HttpServletResponse) res; ServletContext servletContext = getServletContext(); String timerKey = "FilterDispatcher_doFilter: "; try { UtilTimerStack.push(timerKey); request = prepareDispatcherAndWrapRequest(request, response); ActionMapping mapping; try { mapping = actionMapper.getMapping(request, dispatcher.getConfigurationManager()); } catch (Exception ex) { LOG.error("error getting ActionMapping", ex); dispatcher.sendError(request, response, servletContext, HttpServletResponse.SC_INTERNAL_SERVER_ERROR, ex); return; } if (mapping == null) { // there is no action in this request, should we look for a static resource? String resourcePath = RequestUtils.getServletPath(request); if ("".equals(resourcePath) && null != request.getPathInfo()) { resourcePath = request.getPathInfo(); } if (serveStatic && resourcePath.startsWith("/struts")) { String name = resourcePath.substring("/struts".length()); findStaticResource(name, request, response); } else { // this is a normal request, let it pass through chain.doFilter(request, response); } // The framework did its job here return; } dispatcher.serviceAction(request, response, servletContext, mapping); } finally { try { ActionContextCleanUp.cleanUp(req); } finally { UtilTimerStack.pop(timerKey); } }
protected java.io.InputStream	findInputStream(java.lang.String name, java.lang.String packagePrefix) Look for a static resource in the classpath. param name The resource name param packagePrefix The package prefix to use to locate the resource return The inputstream of the resource throws IOException If there is a problem locating the resource String resourcePath; if (packagePrefix.endsWith("/") && name.startsWith("/")) { resourcePath = packagePrefix + name.substring(1); } else { resourcePath = packagePrefix + name; } resourcePath = URLDecoder.decode(resourcePath, encoding); return ClassLoaderUtil.getResourceAsStream(resourcePath, getClass());
protected void	findStaticResource(java.lang.String name, javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) Locate a static resource and copy directly to the response, setting the appropriate caching headers. param name The resource name param request The request param response The response throws IOException If anything goes wrong if (!name.endsWith(".class")) { for (String pathPrefix : pathPrefixes) { InputStream is = findInputStream(name, pathPrefix); if (is != null) { Calendar cal = Calendar.getInstance(); // check for if-modified-since, prior to any other headers long ifModifiedSince = 0; try { ifModifiedSince = request.getDateHeader("If-Modified-Since"); } catch (Exception e) { LOG.warn("Invalid If-Modified-Since header value: '" + request.getHeader("If-Modified-Since") + "', ignoring"); } long lastModifiedMillis = lastModifiedCal.getTimeInMillis(); long now = cal.getTimeInMillis(); cal.add(Calendar.DAY_OF_MONTH, 1); long expires = cal.getTimeInMillis(); if (ifModifiedSince > 0 && ifModifiedSince <= lastModifiedMillis) { // not modified, content is not sent - only basic headers and status SC_NOT_MODIFIED response.setDateHeader("Expires", expires); response.setStatus(HttpServletResponse.SC_NOT_MODIFIED); is.close(); return; } // set the content-type header String contentType = getContentType(name); if (contentType != null) { response.setContentType(contentType); } if (serveStaticBrowserCache) { // set heading information for caching static content response.setDateHeader("Date", now); response.setDateHeader("Expires", expires); response.setDateHeader("Retry-After", expires); response.setHeader("Cache-Control", "public"); response.setDateHeader("Last-Modified", lastModifiedMillis); } else { response.setHeader("Cache-Control", "no-cache"); response.setHeader("Pragma", "no-cache"); response.setHeader("Expires", "-1"); } try { copy(is, response.getOutputStream()); } finally { is.close(); } return; } } } response.sendError(HttpServletResponse.SC_NOT_FOUND);
protected java.lang.String	getContentType(java.lang.String name) Determine the content type for the resource name. param name The resource name return The mime type // NOT using the code provided activation.jar to avoid adding yet another dependency // this is generally OK, since these are the main files we server up if (name.endsWith(".js")) { return "text/javascript"; } else if (name.endsWith(".css")) { return "text/css"; } else if (name.endsWith(".html")) { return "text/html"; } else if (name.endsWith(".txt")) { return "text/plain"; } else if (name.endsWith(".gif")) { return "image/gif"; } else if (name.endsWith(".jpg") || name.endsWith(".jpeg")) { return "image/jpeg"; } else if (name.endsWith(".png")) { return "image/png"; } else { return null; }
protected javax.servlet.FilterConfig	getFilterConfig() Expose the FilterConfig instance. return Our FilterConfit instance return filterConfig;
protected javax.servlet.ServletContext	getServletContext() Provide a workaround for some versions of WebLogic. Servlet 2.3 specifies that the servlet context can be retrieved from the session. Unfortunately, some versions of WebLogic can only retrieve the servlet context from the filter config. Hence, this method enables subclasses to retrieve the servlet context from other sources. return the servlet context. return filterConfig.getServletContext();
public void	init(javax.servlet.FilterConfig filterConfig) Initializes the filter by creating a default dispatcher and setting the default packages for static resources. param filterConfig The filter configuration this.filterConfig = filterConfig; dispatcher = createDispatcher(filterConfig); dispatcher.init(); String param = filterConfig.getInitParameter("packages"); String packages = "org.apache.struts2.static template org.apache.struts2.interceptor.debugging"; if (param != null) { packages = param + " " + packages; } this.pathPrefixes = parse(packages);
protected java.lang.String[]	parse(java.lang.String packages) Create a string array from a comma-delimited list of packages. param packages A comma-delimited String listing packages return A string array of packages if (packages == null) { return null; } List<String> pathPrefixes = new ArrayList<String>(); StringTokenizer st = new StringTokenizer(packages, ", \n\t"); while (st.hasMoreTokens()) { String pathPrefix = st.nextToken().replace('.", '/"); if (!pathPrefix.endsWith("/")) { pathPrefix += "/"; } pathPrefixes.add(pathPrefix); } return pathPrefixes.toArray(new String[pathPrefixes.size()]);
protected javax.servlet.http.HttpServletRequest	prepareDispatcherAndWrapRequest(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) Wrap and return the given request, if needed, so as to to transparently handle multipart data as a wrapped class around the given request. param request Our ServletRequest object param response Our ServerResponse object return Wrapped HttpServletRequest object throws ServletException on any error Dispatcher du = Dispatcher.getInstance(); // Prepare and wrap the request if the cleanup filter hasn't already, cleanup filter should be // configured first before struts2 dispatcher filter, hence when its cleanup filter's turn, // static instance of Dispatcher should be null. if (du == null) { Dispatcher.setInstance(dispatcher); // prepare the request no matter what - this ensures that the proper character encoding // is used before invoking the mapper (see WW-9127) dispatcher.prepare(request, response); } else { dispatcher = du; } try { // Wrap request first, just in case it is multipart/form-data // parameters might not be accessible through before encoding (ww-1278) request = dispatcher.wrapRequest(request, getServletContext()); } catch (IOException e) { String message = "Could not wrap servlet request with MultipartRequestWrapper!"; LOG.error(message, e); throw new ServletException(message, e); } return request;
public static void	setActionMapper(org.apache.struts2.dispatcher.mapper.ActionMapper mapper) Modify ActionMapper instance. param mapper New instance actionMapper = mapper;
public static void	setEncoding(java.lang.String val) Modify state of StrutsConstants.STRUTS_I18N_ENCODING setting. param val New setting encoding = val;
public static void	setServeStaticBrowserCache(java.lang.String val) Modify state of StrutsConstants.STRUTS_SERVE_STATIC_BROWSER_CACHE setting. param val New setting serveStaticBrowserCache = "true".equals(val);
public static void	setServeStaticContent(java.lang.String val) Modify state of StrutsConstants.STRUTS_SERVE_STATIC_CONTENT setting. param val New setting serveStatic = "true".equals(val);