Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
TemplateServlet |
|
| 2.5;2.5 |
1 | /* | |
2 | * $Source$ | |
3 | * $Revision$ | |
4 | * | |
5 | * Copyright (C) 2000 Tim Joyce | |
6 | * | |
7 | * Part of Melati (http://melati.org), a framework for the rapid | |
8 | * development of clean, maintainable web applications. | |
9 | * | |
10 | * Melati is free software; Permission is granted to copy, distribute | |
11 | * and/or modify this software under the terms either: | |
12 | * | |
13 | * a) the GNU General Public License as published by the Free Software | |
14 | * Foundation; either version 2 of the License, or (at your option) | |
15 | * any later version, | |
16 | * | |
17 | * or | |
18 | * | |
19 | * b) any version of the Melati Software License, as published | |
20 | * at http://melati.org | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License and | |
23 | * the Melati Software License along with this program; | |
24 | * if not, write to the Free Software Foundation, Inc., | |
25 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the | |
26 | * GNU General Public License and visit http://melati.org to obtain the | |
27 | * Melati Software License. | |
28 | * | |
29 | * Feel free to contact the Developers of Melati (http://melati.org), | |
30 | * if you would like to work out a different arrangement than the options | |
31 | * outlined here. It is our intention to allow Melati to be used by as | |
32 | * wide an audience as possible. | |
33 | * | |
34 | * This program is distributed in the hope that it will be useful, | |
35 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
36 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
37 | * GNU General Public License for more details. | |
38 | * | |
39 | * Contact details for copyright holder: | |
40 | * | |
41 | * Tim Joyce <timj At paneris.org> | |
42 | * http://paneris.org/ | |
43 | * 68 Sandbanks Rd, Poole, Dorset. BH14 8BY. UK | |
44 | */ | |
45 | ||
46 | package org.melati.servlet; | |
47 | ||
48 | import java.io.PrintWriter; | |
49 | import java.io.StringWriter; | |
50 | ||
51 | import javax.servlet.ServletException; | |
52 | import javax.servlet.ServletConfig; | |
53 | ||
54 | import org.melati.Melati; | |
55 | import org.melati.util.MelatiWriter; | |
56 | import org.melati.template.ServletTemplateEngine; | |
57 | import org.melati.template.ServletTemplateContext; | |
58 | import org.melati.template.MultipartTemplateContext; | |
59 | import org.melati.template.Template; | |
60 | ||
61 | /** | |
62 | * Base class to use Melati with a Template Engine. | |
63 | * To create your own servlet simply extend this class, | |
64 | * overriding the <code>doTemplateRequest</code> method. | |
65 | * | |
66 | * @author Tim Joyce | |
67 | * $Revision$ | |
68 | */ | |
69 | 18 | public abstract class TemplateServlet extends PoemServlet { |
70 | ||
71 | /** | |
72 | * Eclipse generated. | |
73 | */ | |
74 | private static final long serialVersionUID = -5228388231472549208L; | |
75 | ||
76 | // the template engine | |
77 | protected ServletTemplateEngine templateEngine; | |
78 | ||
79 | /** | |
80 | * Initialise the template engine. | |
81 | * | |
82 | * @param config a <code>ServletConfig</code> | |
83 | * @throws ServletException if the ServletTemplateEngine has a problem | |
84 | */ | |
85 | public void init(ServletConfig config) throws ServletException { | |
86 | 18 | super.init(config); |
87 | 18 | templateEngine = melatiConfig.getServletTemplateEngine(); |
88 | 18 | templateEngine.init(melatiConfig, this); |
89 | 18 | } |
90 | ||
91 | /** | |
92 | * Set the ServletTemplateEngine and ServletTemplateContext in our Melati. | |
93 | * This allows us to parse any uploaded files before we enter | |
94 | * our PoemSession (so we don't hang on to transactions | |
95 | * unnecessarily). | |
96 | * | |
97 | * @param melati the current Melati | |
98 | * @throws Exception if anything goes wrong | |
99 | */ | |
100 | protected void prePoemSession(Melati melati) throws Exception { | |
101 | // for this request, set the Initialised Template Engine | |
102 | 509 | melati.setTemplateEngine(templateEngine); |
103 | 509 | ServletTemplateContext templateContext = |
104 | 509 | templateEngine.getServletTemplateContext(melati); |
105 | ||
106 | 509 | melati.setTemplateContext(templateContext); |
107 | 509 | } |
108 | ||
109 | protected void doPoemRequest(Melati melati) throws Exception { | |
110 | 507 | ServletTemplateContext templateContext = melati.getServletTemplateContext(); |
111 | // If we have a multi-part form, we use a different template context | |
112 | // which allows us to access the uploaded files as well as fields. | |
113 | // This used to be in prePoemSession, but the use case was pretty thin, | |
114 | // the main Adaptor is PoemFileFormDataAdaptor, which needs to be in session. | |
115 | 507 | String contentType = melati.getRequest().getHeader("content-type"); |
116 | 507 | if (contentType != null && contentType.length() >= 19 && |
117 | 40 | contentType.substring(0,19).equalsIgnoreCase("multipart/form-data")) { |
118 | 7 | templateContext = |
119 | new MultipartTemplateContext(melati, templateContext); | |
120 | } | |
121 | ||
122 | 507 | templateContext.put("melati", melati); |
123 | 507 | templateContext.put("ml", melati.getMarkupLanguage()); |
124 | ||
125 | 507 | String templateName = doTemplateRequest(melati,templateContext); |
126 | ||
127 | // only expand a template if we have one (it could be a redirect) | |
128 | 498 | if (templateName != null) { |
129 | 490 | templateName = addExtension(templateName); |
130 | 490 | templateEngine.expandTemplate(melati.getWriter(), |
131 | templateName, | |
132 | templateContext); | |
133 | } | |
134 | 494 | } |
135 | ||
136 | /** | |
137 | * The template extension is added in an overridable method | |
138 | * to allow the application developer to specify their own template | |
139 | * extensions. | |
140 | * <p> | |
141 | * To obtain nice URLs one method is to call your templates | |
142 | * <code>foo.html.wm</code> for example, your urls can then look like | |
143 | * <code>servlet/db/table/troid/method.html</code>. | |
144 | */ | |
145 | protected String addExtension(String templateName) { | |
146 | 490 | if (!templateName.endsWith(templateEngine.templateExtension())) |
147 | 490 | return templateName + templateEngine.templateExtension(); |
148 | else | |
149 | 0 | return templateName; |
150 | } | |
151 | ||
152 | ||
153 | /** | |
154 | * Send an error message. | |
155 | * | |
156 | * Single call to the templet loader giving purpose (error) and | |
157 | * Exception class. | |
158 | * | |
159 | * This will look in the purpose directory, | |
160 | * the standard templet directory and the classpath, in that order, | |
161 | * for a templet. | |
162 | * This can no longer fail with NotFoundException, | |
163 | * as the Object templet will always be found | |
164 | * (or this is a broken installation). | |
165 | * | |
166 | * @param melati the {@link Melati} | |
167 | * @param e the {@link Exception} to report | |
168 | */ | |
169 | public void error(Melati melati, Exception e) { | |
170 | 20 | melati.getResponse().setStatus(httpStatusCode(e)); |
171 | 20 | ServletTemplateContext templateContext = melati.getServletTemplateContext(); |
172 | // If this a DB error which has occurred prior to | |
173 | // the establishment of a template context | |
174 | 20 | if (templateContext == null) { |
175 | 0 | super.error(melati, e); |
176 | } else | |
177 | ||
178 | // has it been trapped already, if so, we don't need to relog it here | |
179 | 20 | if (!(e instanceof TrappedException)) { |
180 | try { | |
181 | // log it | |
182 | 10 | e.printStackTrace(System.err); |
183 | // and put it on the page | |
184 | 10 | MelatiWriter mw = melati.getWriter(); |
185 | // get rid of anything that has been written so far | |
186 | 10 | mw.reset(); |
187 | 10 | templateContext.put("melati",melati); |
188 | 10 | templateContext.put("ml", melati.getMarkupLanguage()); |
189 | 10 | templateContext.put("object", e); |
190 | 10 | StringWriter sw = new StringWriter(); |
191 | 10 | e.printStackTrace(new PrintWriter(sw)); |
192 | 10 | templateContext.put("error",sw); |
193 | 10 | templateContext.put("sysAdminName", getSysAdminName()); |
194 | 10 | templateContext.put("sysAdminEmail", getSysAdminEmail()); |
195 | ||
196 | Template errorTemplate; | |
197 | 10 | errorTemplate = melati.getConfig().getTempletLoader(). |
198 | 10 | templet(melati.getTemplateEngine(), melati.getMarkupLanguage(),"error", e.getClass()); |
199 | 10 | templateEngine.expandTemplate(mw, errorTemplate, templateContext); |
200 | 10 | melati.write(); |
201 | 0 | } catch (Exception f) { |
202 | 0 | System.err.println("Error finding/writing error template:"); |
203 | 0 | f.printStackTrace(); |
204 | 0 | super.error(melati,e); |
205 | 10 | } |
206 | } | |
207 | 20 | } |
208 | ||
209 | ||
210 | /** | |
211 | * Prepare context and establish name of template to interpolate against it. | |
212 | * | |
213 | * Override this method to build up your own output. | |
214 | * | |
215 | * @param melati the current Melati | |
216 | * @param templateContext the current <code>ServletTemplateContext</code> | |
217 | * @return a Template name, possibly excluding extension. | |
218 | */ | |
219 | protected abstract String doTemplateRequest(Melati melati, | |
220 | ServletTemplateContext templateContext) | |
221 | throws Exception; | |
222 | } |