01: /*
02: * This file is part of the Echo Web Application Framework (hereinafter "Echo").
03: * Copyright (C) 2002-2005 NextApp, Inc.
04: *
05: * Version: MPL 1.1/GPL 2.0/LGPL 2.1
06: *
07: * The contents of this file are subject to the Mozilla Public License Version
08: * 1.1 (the "License"); you may not use this file except in compliance with
09: * the License. You may obtain a copy of the License at
10: * http://www.mozilla.org/MPL/
11: *
12: * Software distributed under the License is distributed on an "AS IS" basis,
13: * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
14: * for the specific language governing rights and limitations under the
15: * License.
16: *
17: * Alternatively, the contents of this file may be used under the terms of
18: * either the GNU General Public License Version 2 or later (the "GPL"), or
19: * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
20: * in which case the provisions of the GPL or the LGPL are applicable instead
21: * of those above. If you wish to allow use of your version of this file only
22: * under the terms of either the GPL or the LGPL, and not to allow others to
23: * use your version of this file under the terms of the MPL, indicate your
24: * decision by deleting the provisions above and replace them with the notice
25: * and other provisions required by the GPL or the LGPL. If you do not delete
26: * the provisions above, a recipient may use your version of this file under
27: * the terms of any one of the MPL, the GPL or the LGPL.
28: */
29:
30: package nextapp.echo2.webcontainer.image;
31:
32: import java.io.IOException;
33:
34: import nextapp.echo2.app.ImageReference;
35: import nextapp.echo2.app.StreamImageReference;
36: import nextapp.echo2.webrender.Connection;
37: import nextapp.echo2.webrender.ContentType;
38: import nextapp.echo2.webrender.WebRenderServlet;
39:
40: /**
41: * Renders a <code>StreamImageReference</code> to the client.
42: */
43: public class StreamImageService extends AbstractImageService {
44:
45: /** <code>Service</code> identifier. */
46: private static final String SERVICE_ID = "Echo.StreamImage";
47:
48: /** Singleton instance of this <code>Service</code>. */
49: public static final StreamImageService INSTANCE = new StreamImageService();
50:
51: static {
52: WebRenderServlet.getServiceRegistry().add(INSTANCE);
53: }
54:
55: /**
56: * @see nextapp.echo2.webrender.Service#getId()
57: */
58: public String getId() {
59: return SERVICE_ID;
60: }
61:
62: /**
63: * @see nextapp.echo2.webrender.Service#getVersion()
64: */
65: public int getVersion() {
66: return 0; // Enable caching.
67: }
68:
69: /**
70: * @see nextapp.echo2.webcontainer.image.AbstractImageService#renderImage(
71: * nextapp.echo2.webrender.Connection, nextapp.echo2.app.ImageReference)
72: */
73: public void renderImage(Connection conn,
74: ImageReference imageReference) throws IOException {
75: try {
76: if (!(imageReference instanceof StreamImageReference)) {
77: throw new IOException(
78: "Image is not a StreamImageReference.");
79: }
80: StreamImageReference streamImageReference = (StreamImageReference) imageReference;
81: conn.setContentType(new ContentType(streamImageReference
82: .getContentType(), true));
83: streamImageReference.render(conn.getOutputStream());
84: } catch (IOException ex) {
85: // Internet Explorer appears to enjoy making half-hearted requests for images, wherein it resets the connection
86: // leaving us with an IOException. This exception is silently eaten.
87: // It would preferable to only ignore SocketExceptions, however the API documentation does not provide
88: // enough information to suggest that such a strategy would be adequate..
89: }
90: }
91: }
|