SWF-470 - Change Spring Faces resource server (CSS/JS/etc) to use Spring MVC infrastructure instead of Web Flow.

spring-faces/src/main/java/org/springframework/faces/ui/resource/FlowResourceHelper.java

@@ -113,8 +113,6 @@ public class FlowResourceHelper {
 			return;
 		}
 
-		RequestContext requestContext = RequestContextHolder.getRequestContext();
-
 		ResponseWriter writer = facesContext.getResponseWriter();
 
 		writer.startElement("script", null);

spring-faces/src/main/java/org/springframework/faces/ui/resource/ResourceServlet.java

@@ -0,0 +1,127 @@
+package org.springframework.faces.ui.resource;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLConnection;
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.util.ClassUtils;
+
+/**
+ * Special action for resolving and rendering static resources from within a JAR file.
+ * 
+ * @author Jeremy Grelle
+ */
+public class ResourceServlet extends HttpServlet {
+
+	private static final String HTTP_CONTENT_LENGTH_HEADER = "Content-Length";
+
+	private static final String HTTP_LAST_MODIFIED_HEADER = "Last-Modified";
+
+	private static final String HTTP_EXPIRES_HEADER = "Expires";
+
+	private static final String HTTP_CACHE_CONTROL_HEADER = "Cache-Control";
+
+	private Map defaultMimeTypes = new HashMap();
+	{
+		defaultMimeTypes.put(".css", "text/css");
+		defaultMimeTypes.put(".gif", "image/gif");
+		defaultMimeTypes.put(".ico", "image/vnd.microsoft.icon");
+		defaultMimeTypes.put(".jpeg", "image/jpeg");
+		defaultMimeTypes.put(".jpg", "image/jpeg");
+		defaultMimeTypes.put(".js", "text/javascript");
+		defaultMimeTypes.put(".png", "image/png");
+	}
+
+	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+
+		URL resource = getRequestResourceURL(request);
+
+		if (resource == null) {
+			response.setStatus(HttpServletResponse.SC_NOT_FOUND);
+			return;
+		}
+
+		URLConnection resourceConn = resource.openConnection();
+		long lastModified = resourceConn.getLastModified();
+
+		String mimeType = getServletContext().getMimeType(resource.getPath());
+		if (mimeType == null) {
+			String extension = resource.getPath().substring(resource.getPath().lastIndexOf('.'));
+			mimeType = (String) defaultMimeTypes.get(extension);
+		}
+		response.setContentType(mimeType);
+
+		response.setHeader(HTTP_CONTENT_LENGTH_HEADER, Long.toString(resourceConn.getContentLength()));
+		response.setDateHeader(HTTP_LAST_MODIFIED_HEADER, lastModified);
+		configureCaching(response, 31556926);
+
+		InputStream in = resourceConn.getInputStream();
+		OutputStream out = response.getOutputStream();
+		try {
+			byte[] buffer = new byte[1024];
+			while (in.available() > 0) {
+				int len = in.read(buffer);
+				out.write(buffer, 0, len);
+			}
+		} finally {
+			in.close();
+			out.close();
+		}
+	}
+
+	protected long getLastModified(HttpServletRequest request) {
+		URL resource;
+		try {
+			resource = getRequestResourceURL(request);
+		} catch (MalformedURLException e) {
+			return -1;
+		}
+
+		if (resource == null) {
+			return -1;
+		}
+
+		URLConnection resourceConn;
+		try {
+			resourceConn = resource.openConnection();
+		} catch (IOException e) {
+			return -1;
+		}
+		return resourceConn.getLastModified();
+	}
+
+	private URL getRequestResourceURL(HttpServletRequest request) throws MalformedURLException {
+		String localResourcePath = request.getPathInfo().toString();
+		String jarResourcePath = "META-INF" + request.getPathInfo().toString();
+
+		URL resource;
+
+		resource = getServletContext().getResource(localResourcePath);
+		if (resource == null) {
+			resource = ClassUtils.getDefaultClassLoader().getResource(jarResourcePath);
+		}
+
+		return resource;
+	}
+
+	/**
+	 * Set HTTP headers to allow caching for the given number of seconds.
+	 * @param seconds number of seconds into the future that the response should be cacheable for
+	 */
+	private void configureCaching(HttpServletResponse response, int seconds) {
+		// HTTP 1.0 header
+		response.setDateHeader(HTTP_EXPIRES_HEADER, System.currentTimeMillis() + seconds * 1000L);
+		// HTTP 1.1 header
+		response.setHeader(HTTP_CACHE_CONTROL_HEADER, "max-age=" + seconds);
+	}
+}