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comparison dwtx/jface/internal/text/revisions/Range.d @ 129:eb30df5ca28b

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Added JFace Text sources
author Frank Benoit <benoit@tionex.de>
date Sat, 23 Aug 2008 19:10:48 +0200
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128:8df1d4193877 129:eb30df5ca28b
1 /*******************************************************************************
2 * Copyright (c) 2006 IBM Corporation and others.
3 * All rights reserved. This program and the accompanying materials
4 * are made available under the terms of the Eclipse Public License v1.0
5 * which accompanies this distribution, and is available at
6 * http://www.eclipse.org/legal/epl-v10.html
7 *
8 * Contributors:
9 * IBM Corporation - initial API and implementation
10 * Port to the D programming language:
11 * Frank Benoit <benoit@tionex.de>
12 *******************************************************************************/
13 module dwtx.jface.internal.text.revisions.Range;
14
15 import dwt.dwthelper.utils;
16
17 import dwtx.jface.text.source.ILineRange;
18
19 /**
20 * A variable {@link dwtx.jface.text.source.ILineRange} with the following invariant:
21 * <ul>
22 * <li>{@link #start() start} &gt;= 0
23 * <li>{@link #length() length} &gt; 0, i.e. a range cannot be empty
24 * </ul>
25 * <p>
26 * Attempts to create or modify a <code>Range</code> such that this invariant would be violated
27 * result in a {@link LineIndexOutOfBoundsException} being
28 * thrown.
29 * </p>
30 *
31 * @since 3.2
32 */
33 public final class Range : ILineRange, Cloneable {
34 /**
35 * Creates a new range with the same start and length as the passed line range.
36 *
37 * @param range the range to copy
38 * @return a <code>Range</code> with the same start and length as <code>range</code>
39 * @throws LineIndexOutOfBoundsException if the passed {@link ILineRange} does not adhere to the
40 * contract of {@link Range}
41 */
42 public static Range copy(ILineRange range) throws LineIndexOutOfBoundsException {
43 return createRelative(range.getStartLine(), range.getNumberOfLines());
44 }
45
46 /**
47 * Creates a new range equal to the passed line range.
48 *
49 * @param range the range to copy
50 * @return a <code>Range</code> equal to <code>range</code>
51 */
52 public static Range copy(Range range) {
53 return createRelative(range.start(), range.length());
54 }
55
56 /**
57 * Creates a new range with the given start offset and length.
58 *
59 * @param start the first line of the new range, must be &gt;= 0
60 * @param length the number of lines included in the new range, must be &gt; 0
61 * @return a <code>Range</code> with the given start and length
62 * @throws LineIndexOutOfBoundsException if the parameters violate the invariant of
63 * {@link Range}
64 */
65 public static Range createRelative(int start, int length) throws LineIndexOutOfBoundsException {
66 return new Range(start, length);
67 }
68
69 /**
70 * Creates a new range with the given start and end offsets.
71 *
72 * @param start the first line of the new range, must be &gt;= 0
73 * @param end the first line not in the range any more (exclusive), must be &gt; <code>start</code>
74 * @return a <code>Range</code> with the given start and end offsets
75 * @throws LineIndexOutOfBoundsException if the parameters violate the invariant of
76 * {@link Range}
77 */
78 public static Range createAbsolute(int start, int end) {
79 return new Range(start, end - start);
80 }
81
82 private int fStart;
83 private int fLength;
84
85 /*
86 * Private constructor.
87 */
88 private Range(int start, int length) {
89 moveTo(start);
90 setLength(length);
91 }
92
93 /*
94 * @see dwtx.jface.text.source.ILineRange#getStartLine()
95 */
96 public int getStartLine() {
97 return start();
98 }
99
100 /*
101 * @see dwtx.jface.text.source.ILineRange#getNumberOfLines()
102 */
103 public int getNumberOfLines() {
104 return length();
105 }
106
107 /**
108 * Returns the first line contained in this range. Short equivalent of {@link #getStartLine()}.
109 *
110 * @return the first line contained in this range
111 */
112 public int start() {
113 return fStart;
114 }
115
116 /**
117 * Returns the number of lines contained in this range. Short equivalent of {@link #getNumberOfLines()}.
118 *
119 * @return the number of lines contained in this range
120 */
121 public int length() {
122 return fLength;
123 }
124
125 /**
126 * Returns the first line after this range. Equivalent to {@linkplain #start() start} + {@linkplain #length() length}.
127 *
128 * @return the first line after this range
129 */
130 public int end() {
131 return start() + length();
132 }
133
134 /**
135 * Moves the receiver to <code>start</code>, keeping {@link #length()} constant.
136 *
137 * @param start the new start, must be &gt;= 0
138 * @throws LineIndexOutOfBoundsException if <code>start</code> &lt; 0
139 */
140 public void moveTo(int start) throws LineIndexOutOfBoundsException {
141 if (!(start >= 0))
142 throw new LineIndexOutOfBoundsException("Cannot set a negative start: " + start); //$NON-NLS-1$
143 fStart= start;
144 }
145
146 /**
147 * Moves this range such that the {@link #end()} is at <code>end</code>, keeping
148 * {@link #length()} constant.
149 *
150 * @param end the new end
151 * @throws LineIndexOutOfBoundsException if <code>end</code> &lt;= {@link #start()}
152 */
153 public void moveEndTo(int end) throws LineIndexOutOfBoundsException {
154 moveTo(end - length());
155 }
156
157 /**
158 * Moves the range by <code>delta</code> lines, keeping {@link #length()} constant. The
159 * resulting start line must be &gt;= 0.
160 *
161 * @param delta the number of lines to shift the range
162 * @throws LineIndexOutOfBoundsException if <code>-delta</code> &gt; {@link #start()}
163 */
164 public void moveBy(int delta) throws LineIndexOutOfBoundsException {
165 moveTo(start() + delta);
166 }
167
168 /**
169 * Moves the start offset to <code>start</code>, keeping {@link #end()} constant.
170 *
171 * @param start the new start, must be &gt;= 0 and &lt; {@link #end()}
172 * @throws LineIndexOutOfBoundsException if <code>start</code> &lt; 0 or &gt;= {@link #end()}
173 */
174 public void setStart(int start) throws LineIndexOutOfBoundsException {
175 int end= end();
176 if (!(start >= 0 && start < end))
177 throw new LineIndexOutOfBoundsException("Cannot set a negative start: " + start); //$NON-NLS-1$
178 moveTo(start);
179 setEnd(end);
180 }
181
182 /**
183 * Sets the end of this range, keeping {@link #start()} constant.
184 *
185 * @param end the new end, must be &gt; {@link #start()}
186 * @throws LineIndexOutOfBoundsException if <code>end</code> &lt;= {@link #start()}
187 */
188 public void setEnd(int end) throws LineIndexOutOfBoundsException {
189 setLength(end - start());
190 }
191
192 /**
193 * Sets the length of this range, keeping {@link #start()} constant.
194 *
195 * @param length the new length, must be &gt; 0
196 * @throws LineIndexOutOfBoundsException if <code>length</code> &lt;= 0
197 */
198 public void setLength(int length) throws LineIndexOutOfBoundsException {
199 if (!(length > 0))
200 throw new LineIndexOutOfBoundsException("Cannot set length <= 0: " + length); //$NON-NLS-1$
201 fLength= length;
202 }
203
204 /**
205 * Sets the length of this range, keeping {@link #end()} constant.
206 *
207 * @param length the new length, must be &gt; 0 and &lt;= {@link #end()}
208 * @throws LineIndexOutOfBoundsException if <code>length</code> &lt;= 0
209 */
210 public void setLengthAndMove(int length) throws LineIndexOutOfBoundsException {
211 setStart(end() - length);
212 }
213
214 /**
215 * Resizes the range by <code>delta</code> lines, keeping {@link #start()} constant.
216 *
217 * @param delta the number of lines to resize the range
218 * @throws LineIndexOutOfBoundsException if <code>-delta</code> &gt;= {@link #length()}
219 */
220 public void resizeBy(int delta) throws LineIndexOutOfBoundsException {
221 setLength(length() + delta);
222 }
223
224 /**
225 * Resizes the range by <code>delta</code> lines by moving the start offset, {@link #end()} remains unchanged.
226 *
227 * @param delta the number of lines to resize the range
228 * @throws LineIndexOutOfBoundsException if <code>-delta</code> &gt;= {@link #length()}
229 */
230 public void resizeAndMoveBy(int delta) throws LineIndexOutOfBoundsException {
231 setStart(start() + delta);
232 }
233
234 /**
235 * Splits a range off the end of the receiver. The receiver is shortened to only include
236 * <code>remaining</code> lines after the split.
237 *
238 * @param remaining the number of lines to remain in the receiver, must be in [1, {@link #length() length})
239 * @return the split off range
240 * @throws LineIndexOutOfBoundsException if <code>remaining</code>&gt;= {@link #length()} or <code>remaining</code>&ltt;= 0
241 */
242 public Range split(int remaining) throws LineIndexOutOfBoundsException {
243 if (!(remaining < length())) // assert before modification
244 throw new LineIndexOutOfBoundsException("Remaining must be less than length: " + length()); //$NON-NLS-1$
245
246 int splitLength= length() - remaining;
247 setLength(remaining);
248 return new Range(end(), splitLength);
249 }
250
251 /**
252 * Returns <code>true</code> if the passed range has the same offset and length as the receiver.
253 *
254 * @param range another line range to compare the receiver to
255 * @return <code>true</code> if <code>range</code> has the same offset and length as the receiver
256 */
257 public bool equalRange(ILineRange range) {
258 if (range is this)
259 return true;
260 if (range is null)
261 return false;
262 return range.getStartLine() is start() && range.getNumberOfLines() is length();
263 }
264
265 /*
266 * @see java.lang.Object#clone()
267 */
268 public Object clone() {
269 return Range.copy(this);
270 }
271 }