| JSONAction.java |
1 /**
2 * Copyright (c) 2000-2007 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
30 import java.io.PrintWriter;
31
32 import javax.servlet.http.HttpServletRequest;
33 import javax.servlet.http.HttpServletResponse;
34
35 import org.apache.struts.action.Action;
36 import org.apache.struts.action.ActionForm;
37 import org.apache.struts.action.ActionForward;
38 import org.apache.struts.action.ActionMapping;
39
40 /**
41 * <a href="JSONAction.java.html"><b><i>View Source</i></b></a>
42 *
43 * @author Ming-Gih Lam
44 *
45 */
46 public abstract class JSONAction extends Action {
47
48 public ActionForward execute(
49 ActionMapping mapping, ActionForm form, HttpServletRequest req,
50 HttpServletResponse res)
51 throws Exception {
52
53 String callback = ParamUtil.getString(req, "callback");
54 String instance = ParamUtil.getString(req, "inst");
55
56 String json = null;
57
58 try {
59 json = getJSON(mapping, form, req, res);
60
61 if (Validator.isNotNull(callback)) {
62 json = callback + "(" + json + ");";
63 }
64 else if (Validator.isNotNull(instance)) {
65 json = "var " + instance + "=" + json + ";";
66 }
67 }
68 catch (Exception e) {
69 res.sendError(
70 HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e.getMessage());
71
72 return null;
73 }
74
75 if (Validator.isNotNull(json)) {
76 res.setContentType(ContentTypes.TEXT_JAVASCRIPT);
77 res.setHeader(HttpHeaders.CACHE_CONTROL, "no-cache");
78
79 PrintWriter pw = res.getWriter();
80
81 pw.write(json);
82
83 pw.close();
84 }
85
86 return null;
87 }
88
89 public abstract String getJSON(
90 ActionMapping mapping, ActionForm form, HttpServletRequest req,
91 HttpServletResponse res)
92 throws Exception;
93
94 }