| BibleBookList.java |
1 /**
2 * Distribution License:
3 * JSword is free software; you can redistribute it and/or modify it under
4 * the terms of the GNU Lesser General Public License, version 2.1 or later
5 * as published by the Free Software Foundation. This program is distributed
6 * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
7 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
8 * See the GNU Lesser General Public License for more details.
9 *
10 * The License is available on the internet at:
11 * http://www.gnu.org/copyleft/lgpl.html
12 * or by writing to:
13 * Free Software Foundation, Inc.
14 * 59 Temple Place - Suite 330
15 * Boston, MA 02111-1307, USA
16 *
17 * © CrossWire Bible Society, 2012 - 2016
18 *
19 */
20 package org.crosswire.jsword.versification;
21
22 import java.io.Serializable;
23 import java.util.Iterator;
24 import java.util.NoSuchElementException;
25
26 /**
27 * A BibleBookList is an ordered list of one or more BibleBooks.
28 * Typically, a BibleBookList is a member of a Versification.
29 *
30 * @see gnu.lgpl.License The GNU Lesser General Public License for details.
31 * @author DM Smith
32 */
33 /* pkg protected */ class BibleBookList implements Iterable<BibleBook>, Serializable {
34 /**
35 * Create an ordered BibleBookList from the input.
36 * @param books
37 */
38 BibleBookList(BibleBook[] books) {
39 this.books = books.clone();
40 initialize();
41 }
42
43 /**
44 * Does this Versification contain the BibleBook.
45 *
46 * @param book
47 * @return true if it is present.
48 */
49 public boolean contains(BibleBook book) {
50 return book != null && bookMap[book.ordinal()] != -1;
51 }
52
53 /**
54 * Where does the BibleBook come in the order of books of the Bible.
55 * The first book is 0, the next is 1 and so forth.
56 * If the BibleBook is not in this Reference System,
57 * then the return value of this routine is -1.
58 *
59 * @param book
60 * @return the ordinal value of the book or -1 if not present
61 */
62 public int getOrdinal(BibleBook book) {
63 return bookMap[book.ordinal()];
64 }
65
66 /**
67 * Get the number of books in this Versification.
68 * @return the number of books
69 */
70 public int getBookCount() {
71 return books.length;
72 }
73
74 /**
75 * Get the BibleBook by its position in this Versification.
76 * If the position is negative, return the first book.
77 * If the position is greater than the last, return the last book.
78 *
79 * @param ordinal
80 * @return the indicated book
81 */
82 public BibleBook getBook(int ordinal) {
83 int ord = ordinal;
84 if (ord < 0) {
85 ord = 0;
86 }
87 if (ord >= books.length) {
88 ord = books.length - 1;
89 }
90 return books[ord];
91 }
92
93 /**
94 * Get the BibleBooks in this Versification.
95 *
96 * @return an Iterator over the books
97 */
98 public Iterator<BibleBook> iterator() {
99 return new Iterator<BibleBook>() {
100
101 private BibleBook nextBook = books[0];
102
103 public boolean hasNext() {
104 return nextBook != null;
105 }
106
107 public BibleBook next() {
108
109 if (nextBook == null) {
110 throw new NoSuchElementException();
111 }
112
113 BibleBook current = nextBook;
114 nextBook = getNextBook(nextBook);
115 return current;
116 }
117
118 public void remove() {
119 throw new UnsupportedOperationException();
120 }
121
122 };
123 }
124
125 /**
126 * Return the first book in the list.
127 *
128 * @return the first book in the list
129 */
130 public BibleBook getFirstBook() {
131 return books[0];
132 }
133
134 /**
135 * Return the first book in the list.
136 *
137 * @return the first book in the list
138 */
139 public BibleBook getLastBook() {
140 return books[books.length - 1];
141 }
142
143 /**
144 * Given a BibleBook, get the previous BibleBook in this Versification. If it is the first book, return null.
145 * @param book A BibleBook in the Versification
146 * @return the previous BibleBook or null.
147 */
148 public BibleBook getPreviousBook(BibleBook book) {
149 int ordinal = book.ordinal();
150 int position = bookMap[ordinal];
151 if (position > 0) {
152 return books[position - 1];
153 }
154
155 return null;
156 }
157
158 /**
159 * Given a BibleBook, get the next BibleBook in this Versification. If it is the last book, return null.
160 * @param book A BibleBook in the Versification
161 * @return the previous BibleBook or null.
162 */
163 public BibleBook getNextBook(BibleBook book) {
164 int ordinal = book.ordinal();
165 int position = bookMap[ordinal];
166 if (position != -1 && position + 1 < books.length) {
167 return books[position + 1];
168 }
169 return null;
170 }
171
172 /**
173 * The bookMap contains one slot for every BibleBook, indexed by it's ordinal value.
174 * The value of that entry is the position of the book in the BookList.
175 * If the BibleBook is not present in books, it's value is -1.
176 */
177 private void initialize() {
178 bookMap = new int[BibleBook.values().length + 1];
179 // Initialize all slots to -1
180 for (BibleBook b : BibleBook.values()) {
181 bookMap[b.ordinal()] = -1;
182 }
183
184 // Fill in the position of the books into that list
185 for (int i = 0; i < books.length; i++) {
186 bookMap[books[i].ordinal()] = i;
187 }
188 }
189
190 /** The ordered books in this list */
191 protected BibleBook[] books;
192
193 /** The bookMap maps from a BibleBook to the position that it has in <code>books</code>. */
194 private int[] bookMap;
195
196 /**
197 * Serialization ID
198 */
199 private static final long serialVersionUID = -2681289798451902815L;
200 }
201