| JSONAction.java |
1 /**
2 * Copyright (c) 2000-2008 Liferay, Inc. All rights reserved.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20 * SOFTWARE.
21 */
22
23 package com.liferay.portal.struts;
24
25 import com.liferay.portal.kernel.servlet.HttpHeaders;
26 import com.liferay.portal.kernel.util.ContentTypes;
27 import com.liferay.portal.kernel.util.ParamUtil;
28 import com.liferay.portal.kernel.util.Validator;
29 import com.liferay.portal.util.PortalUtil;
30
31 import java.io.PrintWriter;
32
33 import javax.servlet.http.HttpServletRequest;
34 import javax.servlet.http.HttpServletResponse;
35
36 import org.apache.struts.action.Action;
37 import org.apache.struts.action.ActionForm;
38 import org.apache.struts.action.ActionForward;
39 import org.apache.struts.action.ActionMapping;
40
41 /**
42 * <a href="JSONAction.java.html"><b><i>View Source</i></b></a>
43 *
44 * @author Ming-Gih Lam
45 *
46 */
47 public abstract class JSONAction extends Action {
48
49 public ActionForward execute(
50 ActionMapping mapping, ActionForm form, HttpServletRequest req,
51 HttpServletResponse res)
52 throws Exception {
53
54 String callback = ParamUtil.getString(req, "callback");
55 String instance = ParamUtil.getString(req, "inst");
56
57 String json = null;
58
59 try {
60 json = getJSON(mapping, form, req, res);
61
62 if (Validator.isNotNull(callback)) {
63 json = callback + "(" + json + ");";
64 }
65 else if (Validator.isNotNull(instance)) {
66 json = "var " + instance + "=" + json + ";";
67 }
68 }
69 catch (Exception e) {
70 PortalUtil.sendError(
71 HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e, req, res);
72
73 return null;
74 }
75
76 if (Validator.isNotNull(json)) {
77 res.setContentType(ContentTypes.TEXT_JAVASCRIPT);
78 res.setHeader(HttpHeaders.CACHE_CONTROL, "no-cache");
79
80 PrintWriter pw = res.getWriter();
81
82 pw.write(json);
83
84 pw.close();
85 }
86
87 return null;
88 }
89
90 public abstract String getJSON(
91 ActionMapping mapping, ActionForm form, HttpServletRequest req,
92 HttpServletResponse res)
93 throws Exception;
94
95 }