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1   /*
2    * Copyright (C) 2007, Dave Watson <dwatson@mimvista.com>
3    * Copyright (C) 2006-2007, Robin Rosenberg <robin.rosenberg@dewire.com>
4    * Copyright (C) 2006-2007, Shawn O. Pearce <spearce@spearce.org>
5    * and other copyright owners as documented in the project's IP log.
6    *
7    * This program and the accompanying materials are made available
8    * under the terms of the Eclipse Distribution License v1.0 which
9    * accompanies this distribution, is reproduced below, and is
10   * available at http://www.eclipse.org/org/documents/edl-v10.php
11   *
12   * All rights reserved.
13   *
14   * Redistribution and use in source and binary forms, with or
15   * without modification, are permitted provided that the following
16   * conditions are met:
17   *
18   * - Redistributions of source code must retain the above copyright
19   *   notice, this list of conditions and the following disclaimer.
20   *
21   * - Redistributions in binary form must reproduce the above
22   *   copyright notice, this list of conditions and the following
23   *   disclaimer in the documentation and/or other materials provided
24   *   with the distribution.
25   *
26   * - Neither the name of the Eclipse Foundation, Inc. nor the
27   *   names of its contributors may be used to endorse or promote
28   *   products derived from this software without specific prior
29   *   written permission.
30   *
31   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
32   * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
33   * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
34   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
36   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
37   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
38   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
39   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
40   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
43   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
44   */
45  
46  package org.eclipse.jgit.lib;
47  
48  import static java.nio.charset.StandardCharsets.UTF_8;
49  
50  import java.io.ByteArrayOutputStream;
51  import java.io.IOException;
52  import java.io.OutputStreamWriter;
53  import java.io.UnsupportedEncodingException;
54  import java.nio.charset.Charset;
55  import java.util.List;
56  
57  /**
58   * Mutable builder to construct a commit recording the state of a project.
59   *
60   * Applications should use this object when they need to manually construct a
61   * commit and want precise control over its fields. For a higher level interface
62   * see {@link org.eclipse.jgit.api.CommitCommand}.
63   *
64   * To read a commit object, construct a {@link org.eclipse.jgit.revwalk.RevWalk}
65   * and obtain a {@link org.eclipse.jgit.revwalk.RevCommit} instance by calling
66   * {@link org.eclipse.jgit.revwalk.RevWalk#parseCommit(AnyObjectId)}.
67   */
68  public class CommitBuilder {
69  	private static final ObjectId[] EMPTY_OBJECTID_LIST = new ObjectId[0];
70  
71  	private static final byte[] htree = Constants.encodeASCII("tree"); //$NON-NLS-1$
72  
73  	private static final byte[] hparent = Constants.encodeASCII("parent"); //$NON-NLS-1$
74  
75  	private static final byte[] hauthor = Constants.encodeASCII("author"); //$NON-NLS-1$
76  
77  	private static final byte[] hcommitter = Constants.encodeASCII("committer"); //$NON-NLS-1$
78  
79  	private static final byte[] hencoding = Constants.encodeASCII("encoding"); //$NON-NLS-1$
80  
81  	private ObjectId treeId;
82  
83  	private ObjectId[] parentIds;
84  
85  	private PersonIdent author;
86  
87  	private PersonIdent committer;
88  
89  	private String message;
90  
91  	private Charset encoding;
92  
93  	/**
94  	 * Initialize an empty commit.
95  	 */
96  	public CommitBuilder() {
97  		parentIds = EMPTY_OBJECTID_LIST;
98  		encoding = UTF_8;
99  	}
100 
101 	/**
102 	 * Get id of the root tree listing this commit's snapshot.
103 	 *
104 	 * @return id of the root tree listing this commit's snapshot.
105 	 */
106 	public ObjectId getTreeId() {
107 		return treeId;
108 	}
109 
110 	/**
111 	 * Set the tree id for this commit object
112 	 *
113 	 * @param id
114 	 *            the tree identity.
115 	 */
116 	public void setTreeId(AnyObjectId id) {
117 		treeId = id.copy();
118 	}
119 
120 	/**
121 	 * Get the author of this commit (who wrote it).
122 	 *
123 	 * @return the author of this commit (who wrote it).
124 	 */
125 	public PersonIdent getAuthor() {
126 		return author;
127 	}
128 
129 	/**
130 	 * Set the author (name, email address, and date) of who wrote the commit.
131 	 *
132 	 * @param newAuthor
133 	 *            the new author. Should not be null.
134 	 */
135 	public void setAuthor(PersonIdent newAuthor) {
136 		author = newAuthor;
137 	}
138 
139 	/**
140 	 * Get the committer and commit time for this object.
141 	 *
142 	 * @return the committer and commit time for this object.
143 	 */
144 	public PersonIdent getCommitter() {
145 		return committer;
146 	}
147 
148 	/**
149 	 * Set the committer and commit time for this object
150 	 *
151 	 * @param newCommitter
152 	 *            the committer information. Should not be null.
153 	 */
154 	public void setCommitter(PersonIdent newCommitter) {
155 		committer = newCommitter;
156 	}
157 
158 	/**
159 	 * Get the ancestors of this commit.
160 	 *
161 	 * @return the ancestors of this commit. Never null.
162 	 */
163 	public ObjectId[] getParentIds() {
164 		return parentIds;
165 	}
166 
167 	/**
168 	 * Set the parent of this commit.
169 	 *
170 	 * @param newParent
171 	 *            the single parent for the commit.
172 	 */
173 	public void setParentId(AnyObjectId newParent) {
174 		parentIds = new ObjectId[] { newParent.copy() };
175 	}
176 
177 	/**
178 	 * Set the parents of this commit.
179 	 *
180 	 * @param parent1
181 	 *            the first parent of this commit. Typically this is the current
182 	 *            value of the {@code HEAD} reference and is thus the current
183 	 *            branch's position in history.
184 	 * @param parent2
185 	 *            the second parent of this merge commit. Usually this is the
186 	 *            branch being merged into the current branch.
187 	 */
188 	public void setParentIds(AnyObjectId parent1, AnyObjectId parent2) {
189 		parentIds = new ObjectId[] { parent1.copy(), parent2.copy() };
190 	}
191 
192 	/**
193 	 * Set the parents of this commit.
194 	 *
195 	 * @param newParents
196 	 *            the entire list of parents for this commit.
197 	 */
198 	public void setParentIds(ObjectId... newParents) {
199 		parentIds = new ObjectId[newParents.length];
200 		for (int i = 0; i < newParents.length; i++)
201 			parentIds[i] = newParents[i].copy();
202 	}
203 
204 	/**
205 	 * Set the parents of this commit.
206 	 *
207 	 * @param newParents
208 	 *            the entire list of parents for this commit.
209 	 */
210 	public void setParentIds(List<? extends AnyObjectId> newParents) {
211 		parentIds = new ObjectId[newParents.size()];
212 		for (int i = 0; i < newParents.size(); i++)
213 			parentIds[i] = newParents.get(i).copy();
214 	}
215 
216 	/**
217 	 * Add a parent onto the end of the parent list.
218 	 *
219 	 * @param additionalParent
220 	 *            new parent to add onto the end of the current parent list.
221 	 */
222 	public void addParentId(AnyObjectId additionalParent) {
223 		if (parentIds.length == 0) {
224 			setParentId(additionalParent);
225 		} else {
226 			ObjectId[] newParents = new ObjectId[parentIds.length + 1];
227 			System.arraycopy(parentIds, 0, newParents, 0, parentIds.length);
228 			newParents[parentIds.length] = additionalParent.copy();
229 			parentIds = newParents;
230 		}
231 	}
232 
233 	/**
234 	 * Get the complete commit message.
235 	 *
236 	 * @return the complete commit message.
237 	 */
238 	public String getMessage() {
239 		return message;
240 	}
241 
242 	/**
243 	 * Set the commit message.
244 	 *
245 	 * @param newMessage
246 	 *            the commit message. Should not be null.
247 	 */
248 	public void setMessage(String newMessage) {
249 		message = newMessage;
250 	}
251 
252 	/**
253 	 * Set the encoding for the commit information
254 	 *
255 	 * @param encodingName
256 	 *            the encoding name. See
257 	 *            {@link java.nio.charset.Charset#forName(String)}.
258 	 */
259 	public void setEncoding(String encodingName) {
260 		encoding = Charset.forName(encodingName);
261 	}
262 
263 	/**
264 	 * Set the encoding for the commit information
265 	 *
266 	 * @param enc
267 	 *            the encoding to use.
268 	 */
269 	public void setEncoding(Charset enc) {
270 		encoding = enc;
271 	}
272 
273 	/**
274 	 * Get the encoding that should be used for the commit message text.
275 	 *
276 	 * @return the encoding that should be used for the commit message text.
277 	 */
278 	public Charset getEncoding() {
279 		return encoding;
280 	}
281 
282 	/**
283 	 * Format this builder's state as a commit object.
284 	 *
285 	 * @return this object in the canonical commit format, suitable for storage
286 	 *         in a repository.
287 	 * @throws java.io.UnsupportedEncodingException
288 	 *             the encoding specified by {@link #getEncoding()} is not
289 	 *             supported by this Java runtime.
290 	 */
291 	public byte[] build() throws UnsupportedEncodingException {
292 		ByteArrayOutputStream os = new ByteArrayOutputStream();
293 		OutputStreamWriter w = new OutputStreamWriter(os, getEncoding());
294 		try {
295 			os.write(htree);
296 			os.write(' ');
297 			getTreeId().copyTo(os);
298 			os.write('\n');
299 
300 			for (ObjectId p : getParentIds()) {
301 				os.write(hparent);
302 				os.write(' ');
303 				p.copyTo(os);
304 				os.write('\n');
305 			}
306 
307 			os.write(hauthor);
308 			os.write(' ');
309 			w.write(getAuthor().toExternalString());
310 			w.flush();
311 			os.write('\n');
312 
313 			os.write(hcommitter);
314 			os.write(' ');
315 			w.write(getCommitter().toExternalString());
316 			w.flush();
317 			os.write('\n');
318 
319 			if (getEncoding() != UTF_8) {
320 				os.write(hencoding);
321 				os.write(' ');
322 				os.write(Constants.encodeASCII(getEncoding().name()));
323 				os.write('\n');
324 			}
325 
326 			os.write('\n');
327 
328 			if (getMessage() != null) {
329 				w.write(getMessage());
330 				w.flush();
331 			}
332 		} catch (IOException err) {
333 			// This should never occur, the only way to get it above is
334 			// for the ByteArrayOutputStream to throw, but it doesn't.
335 			//
336 			throw new RuntimeException(err);
337 		}
338 		return os.toByteArray();
339 	}
340 
341 	/**
342 	 * Format this builder's state as a commit object.
343 	 *
344 	 * @return this object in the canonical commit format, suitable for storage
345 	 *         in a repository.
346 	 * @throws java.io.UnsupportedEncodingException
347 	 *             the encoding specified by {@link #getEncoding()} is not
348 	 *             supported by this Java runtime.
349 	 */
350 	public byte[] toByteArray() throws UnsupportedEncodingException {
351 		return build();
352 	}
353 
354 	/** {@inheritDoc} */
355 	@SuppressWarnings("nls")
356 	@Override
357 	public String toString() {
358 		StringBuilder r = new StringBuilder();
359 		r.append("Commit");
360 		r.append("={\n");
361 
362 		r.append("tree ");
363 		r.append(treeId != null ? treeId.name() : "NOT_SET");
364 		r.append("\n");
365 
366 		for (ObjectId p : parentIds) {
367 			r.append("parent ");
368 			r.append(p.name());
369 			r.append("\n");
370 		}
371 
372 		r.append("author ");
373 		r.append(author != null ? author.toString() : "NOT_SET");
374 		r.append("\n");
375 
376 		r.append("committer ");
377 		r.append(committer != null ? committer.toString() : "NOT_SET");
378 		r.append("\n");
379 
380 		if (encoding != null && encoding != UTF_8) {
381 			r.append("encoding ");
382 			r.append(encoding.name());
383 			r.append("\n");
384 		}
385 
386 		r.append("\n");
387 		r.append(message != null ? message : "");
388 		r.append("}");
389 		return r.toString();
390 	}
391 }