Created and integrated a RequestHandler for application resources

1 files changed, 138 insertions, 0 deletions

diff --git a/src/com/vaadin/terminal/gwt/server/ApplicationResourceHandler.java b/src/com/vaadin/terminal/gwt/server/ApplicationResourceHandler.java
new file mode 100644
index 0000000000..5c89b64754
--- /dev/null
+++ b/src/com/vaadin/terminal/gwt/server/ApplicationResourceHandler.java
@@ -0,0 +1,138 @@
+package com.vaadin.terminal.gwt.server;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Iterator;
+import java.util.Locale;
+import java.util.TimeZone;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import javax.servlet.http.HttpServletResponse;
+
+import com.vaadin.Application;
+import com.vaadin.terminal.ApplicationResource;
+import com.vaadin.terminal.DownloadStream;
+import com.vaadin.terminal.RequestHandler;
+import com.vaadin.terminal.WrappedRequest;
+import com.vaadin.terminal.WrappedResponse;
+
+public class ApplicationResourceHandler implements RequestHandler {
+    private static final DateFormat HTTP_DATE_FORMAT = new SimpleDateFormat(
+            "EEE, dd MMM yyyy HH:mm:ss zzz", Locale.ENGLISH);
+    static {
+        HTTP_DATE_FORMAT.setTimeZone(TimeZone.getTimeZone("GMT"));
+    }
+    private static final Pattern APP_RESOURCE_PATTERN = Pattern
+            .compile("/APP/(\\d+)/.*");
+
+    public boolean handleRequest(Application application,
+            WrappedRequest request, WrappedResponse response)
+            throws IOException {
+        // Check for application resources
+        String requestPath = request.getRequestPathInfo();
+        Matcher resourceMatcher = APP_RESOURCE_PATTERN.matcher(requestPath);
+
+        if (resourceMatcher.matches()) {
+            ApplicationResource resource = application
+                    .getResource(resourceMatcher.group(1));
+            if (resource != null) {
+                DownloadStream stream = resource.getStream();
+                if (stream != null) {
+                    stream.setCacheTime(resource.getCacheTime());
+                    serveResource(stream, response);
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+
+    protected void serveResource(DownloadStream stream, WrappedResponse response)
+            throws IOException {
+        if (stream.getParameter("Location") != null) {
+            response.setStatus(HttpServletResponse.SC_MOVED_TEMPORARILY);
+            response.setHeader("Location", stream.getParameter("Location"));
+            return;
+        }
+
+        // Download from given stream
+        final InputStream data = stream.getStream();
+        if (data != null) {
+
+            OutputStream out = null;
+            try {
+                // Sets content type
+                response.setContentType(stream.getContentType());
+
+                // Sets cache headers
+                final long cacheTime = stream.getCacheTime();
+                if (cacheTime <= 0) {
+                    response.setHeader("Cache-Control", "no-cache");
+                    response.setHeader("Pragma", "no-cache");
+                    response.setHeader("Expires",
+                            HTTP_DATE_FORMAT.format(new Date(0)));
+                } else {
+                    response.setHeader("Cache-Control", "max-age=" + cacheTime
+                            / 1000);
+                    response.setHeader(
+                            "Expires",
+                            HTTP_DATE_FORMAT.format(new Date(System
+                                    .currentTimeMillis() + cacheTime)));
+                    // Required to apply caching in some Tomcats
+                    response.setHeader("Pragma", "cache");
+                }
+
+                // Copy download stream parameters directly
+                // to HTTP headers.
+                final Iterator<String> i = stream.getParameterNames();
+                if (i != null) {
+                    while (i.hasNext()) {
+                        final String param = i.next();
+                        response.setHeader(param, stream.getParameter(param));
+                    }
+                }
+
+                // suggest local filename from DownloadStream if
+                // Content-Disposition
+                // not explicitly set
+                String contentDispositionValue = stream
+                        .getParameter("Content-Disposition");
+                if (contentDispositionValue == null) {
+                    contentDispositionValue = "filename=\""
+                            + stream.getFileName() + "\"";
+                    response.setHeader("Content-Disposition",
+                            contentDispositionValue);
+                }
+
+                int bufferSize = stream.getBufferSize();
+                if (bufferSize <= 0 || bufferSize > Constants.MAX_BUFFER_SIZE) {
+                    bufferSize = Constants.DEFAULT_BUFFER_SIZE;
+                }
+                final byte[] buffer = new byte[bufferSize];
+                int bytesRead = 0;
+
+                out = response.getOutputStream();
+
+                long totalWritten = 0;
+                while ((bytesRead = data.read(buffer)) > 0) {
+                    out.write(buffer, 0, bytesRead);
+
+                    totalWritten += bytesRead;
+                    if (totalWritten >= buffer.length) {
+                        // Avoid chunked encoding for small resources
+                        out.flush();
+                    }
+                }
+            } finally {
+                AbstractCommunicationManager.tryToCloseStream(out);
+                AbstractCommunicationManager.tryToCloseStream(data);
+            }
+        }
+    }
+}