1 /*
2 * $Source$
3 * $Revision$
4 *
5 * Copyright (C) 2006 Tim Pizey
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 Pizey <timp At paneris.org>
42 * http://paneris.org/~timp
43 */
44 package org.melati.template;
45
46 import java.util.Enumeration;
47 import java.util.Vector;
48
49 /**
50 * Common elements of a TemplateEngine.
51 *
52 */
53 public abstract class AbstractTemplateEngine implements TemplateEngine {
54
55 protected Vector<String> roots = new Vector<String>();
56
57 /**
58 * Constructor.
59 */
60 public AbstractTemplateEngine() {
61 super();
62 addRoot("");
63 }
64
65 /**
66 * {@inheritDoc}
67 * @see org.melati.template.TemplateEngine#getTemplateName(java.lang.String, java.lang.String)
68 */
69 public String getTemplateName(String key, String classifier) {
70 String templateResourceName = null;
71 Enumeration<String> theRoots = getRoots();
72 while(theRoots.hasMoreElements()) {
73 String root = (String)theRoots.nextElement();
74 templateResourceName = "/" + emptyOrSlashEnded(root) +
75 emptyOrSlashEnded(classifier) +
76 key +
77 templateExtension();
78 if (this.getClass().getResource(templateResourceName) == null) {
79 templateResourceName = "/" + emptyOrSlashEnded(root) +
80 key + templateExtension();
81 } else
82 break;
83
84 if (this.getClass().getResource(templateResourceName) != null)
85 break;
86 else
87 templateResourceName = null;
88 }
89 if (templateResourceName == null)
90 return key;
91 else
92 return templateResourceName;
93 }
94
95 private String emptyOrSlashEnded(String in) {
96 if (in == null)
97 return "";
98 if (in.equals(""))
99 return "";
100 if(in.endsWith("/"))
101 return in;
102
103 return in + "/";
104 }
105
106
107 /**
108 * {@inheritDoc}
109 * @see org.melati.template.TemplateEngine#getRoots()
110 */
111 public Enumeration<String> getRoots() {
112 return roots.elements();
113 }
114
115 /**
116 * Add root at index 0,
117 * so that the empty string is always returned last by <code>elements</code>.
118 * @see org.melati.template.TemplateEngine#addRoot(java.lang.String)
119 */
120 public void addRoot(String root) {
121 roots.insertElementAt(root,0);
122 }
123
124 }