1 /*
2 * Zemucan: A Syntax Assistant for DB2
3 * Copyright (C) 2009, 2010 Andres Gomez Casanova
4 *
5 * This file is part of Zemucan.
6 *
7 * Zemucan is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published by
9 * the Free Software Foundation; either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * Zemucan is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, see <http://www.gnu.org/licenses/>.
19 *
20 * Contact:
21 * a n g o c a at y a h o o dot c o m
22 * Cra. 45 No 61 - 31, Bogota, Colombia.
23 *
24 * Author: $LastChangedBy: angoca $:
25 * Date: $LastChangedDate: 2011-03-06 10:15:32 -0500 (dom, 06 mar 2011) $:
26 * Revision: $LastChangedRevision: 1913 $:
27 * URL: $HeadURL: https://zemucan.svn.sourceforge.net/svnroot/zemucan/branches/zemucan_v1/source-code/grammarReaderApi/src/main/java/name/angoca/zemucan/grammarReader/api/AbstractTwoPhaseGrammarReader.java $:
28 */
29 package name.angoca.zemucan.grammarReader.api;
30
31 import java.io.File;
32 import java.net.URISyntaxException;
33 import java.net.URL;
34
35 import name.angoca.zemucan.AbstractZemucanException;
36
37 /**
38 * Represents the grammar read done in two phases. First one is to detect nodes,
39 * and the second one to establish relations between them.
40 * <p>
41 * <b>Control Version</b>
42 * <p>
43 * <ul>
44 * <li>1.0.0 Class creation</li>
45 * </ul>
46 *
47 * @author Andres Gomez Casanova <a
48 * href="mailto:a n g o c a at y a h o o dot c o m" >(AngocA)</a>
49 * @version 1.0.0 2010-10-26
50 */
51 public abstract class AbstractTwoPhaseGrammarReader extends
52 AbstractGrammarReader {
53
54 /**
55 * File descriptor.
56 */
57 protected String fileDescriptor;
58
59 /**
60 * Constructor.
61 */
62 public AbstractTwoPhaseGrammarReader() {
63 super();
64 }
65
66 /**
67 * Scans the document where the nodes are described, and creates the objects
68 * that represents the nodes according to its type.
69 * <p>
70 * This phase only creates independent nodes. The second phase creates the
71 * relations between them.
72 *
73 * @throws AbstractZemucanException
74 */
75 abstract protected void firstPhase() throws AbstractZemucanException;
76
77 /**
78 * Retrieves the set of file names described in the descriptor.
79 *
80 * @return Set of file names.
81 * @throws GeneralGrammarReaderProblemException
82 * If there is a problem interpreting the URL that represents
83 * the file names.
84 */
85 protected String[] getFileNamesFromDescriptor()
86 throws GeneralGrammarReaderProblemException {
87 assert this.fileDescriptor != null;
88
89 String[] files = new String[0];
90 final ClassLoader loader = ClassLoader.getSystemClassLoader();
91 if (loader != null) {
92 final URL url = loader.getResource(this.fileDescriptor);
93 if ((url != null) && url.getProtocol().equals("file")) {
94 File file = null;
95 try {
96 file = new File(url.toURI());
97 } catch (final URISyntaxException exception) {
98 throw new GeneralGrammarReaderProblemException(exception);
99 }
100 if (file.isDirectory()) {
101 files = file.list();
102 } // else The file represents one file.
103 }// else The url is not for a file.
104 } else {
105 assert false;
106 }
107 return files;
108 }
109
110 /**
111 * Second phase of the process where the relations between nodes are
112 * established.
113 *
114 * @throws AbstractZemucanException
115 * If there is a problem while regarding the nodes or
116 */
117 abstract protected void secondPhase() throws AbstractZemucanException;
118
119 }