1 /* 2 * Copyright (C) 2008, Google Inc. 3 * Copyright (C) 2008, Robin Rosenberg <robin.rosenberg@dewire.com> 4 * Copyright (C) 2006-2017, 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.nio.ByteBuffer; 51 import java.nio.charset.Charset; 52 import java.security.MessageDigest; 53 import java.security.NoSuchAlgorithmException; 54 import java.text.MessageFormat; 55 56 import org.eclipse.jgit.errors.CorruptObjectException; 57 import org.eclipse.jgit.internal.JGitText; 58 import org.eclipse.jgit.util.MutableInteger; 59 60 /** 61 * Misc. constants used throughout JGit. 62 */ 63 @SuppressWarnings("nls") 64 public final class Constants { 65 /** Hash function used natively by Git for all objects. */ 66 private static final String HASH_FUNCTION = "SHA-1"; 67 68 /** 69 * A Git object hash is 160 bits, i.e. 20 bytes. 70 * <p> 71 * Changing this assumption is not going to be as easy as changing this 72 * declaration. 73 */ 74 public static final int OBJECT_ID_LENGTH = 20; 75 76 /** 77 * A Git object can be expressed as a 40 character string of hexadecimal 78 * digits. 79 * 80 * @see #OBJECT_ID_LENGTH 81 */ 82 public static final int OBJECT_ID_STRING_LENGTH = OBJECT_ID_LENGTH * 2; 83 84 /** Special name for the "HEAD" symbolic-ref. */ 85 public static final String HEAD = "HEAD"; 86 87 /** Special name for the "FETCH_HEAD" symbolic-ref. */ 88 public static final String FETCH_HEAD = "FETCH_HEAD"; 89 90 /** 91 * Text string that identifies an object as a commit. 92 * <p> 93 * Commits connect trees into a string of project histories, where each 94 * commit is an assertion that the best way to continue is to use this other 95 * tree (set of files). 96 */ 97 public static final String TYPE_COMMIT = "commit"; 98 99 /** 100 * Text string that identifies an object as a blob. 101 * <p> 102 * Blobs store whole file revisions. They are used for any user file, as 103 * well as for symlinks. Blobs form the bulk of any project's storage space. 104 */ 105 public static final String TYPE_BLOB = "blob"; 106 107 /** 108 * Text string that identifies an object as a tree. 109 * <p> 110 * Trees attach object ids (hashes) to names and file modes. The normal use 111 * for a tree is to store a version of a directory and its contents. 112 */ 113 public static final String TYPE_TREE = "tree"; 114 115 /** 116 * Text string that identifies an object as an annotated tag. 117 * <p> 118 * Annotated tags store a pointer to any other object, and an additional 119 * message. It is most commonly used to record a stable release of the 120 * project. 121 */ 122 public static final String TYPE_TAG = "tag"; 123 124 private static final byte[] ENCODED_TYPE_COMMIT = encodeASCII(TYPE_COMMIT); 125 126 private static final byte[] ENCODED_TYPE_BLOB = encodeASCII(TYPE_BLOB); 127 128 private static final byte[] ENCODED_TYPE_TREE = encodeASCII(TYPE_TREE); 129 130 private static final byte[] ENCODED_TYPE_TAG = encodeASCII(TYPE_TAG); 131 132 /** An unknown or invalid object type code. */ 133 public static final int OBJ_BAD = -1; 134 135 /** 136 * In-pack object type: extended types. 137 * <p> 138 * This header code is reserved for future expansion. It is currently 139 * undefined/unsupported. 140 */ 141 public static final int OBJ_EXT = 0; 142 143 /** 144 * In-pack object type: commit. 145 * <p> 146 * Indicates the associated object is a commit. 147 * <p> 148 * <b>This constant is fixed and is defined by the Git packfile format.</b> 149 * 150 * @see #TYPE_COMMIT 151 */ 152 public static final int OBJ_COMMIT = 1; 153 154 /** 155 * In-pack object type: tree. 156 * <p> 157 * Indicates the associated object is a tree. 158 * <p> 159 * <b>This constant is fixed and is defined by the Git packfile format.</b> 160 * 161 * @see #TYPE_BLOB 162 */ 163 public static final int OBJ_TREE = 2; 164 165 /** 166 * In-pack object type: blob. 167 * <p> 168 * Indicates the associated object is a blob. 169 * <p> 170 * <b>This constant is fixed and is defined by the Git packfile format.</b> 171 * 172 * @see #TYPE_BLOB 173 */ 174 public static final int OBJ_BLOB = 3; 175 176 /** 177 * In-pack object type: annotated tag. 178 * <p> 179 * Indicates the associated object is an annotated tag. 180 * <p> 181 * <b>This constant is fixed and is defined by the Git packfile format.</b> 182 * 183 * @see #TYPE_TAG 184 */ 185 public static final int OBJ_TAG = 4; 186 187 /** In-pack object type: reserved for future use. */ 188 public static final int OBJ_TYPE_5 = 5; 189 190 /** 191 * In-pack object type: offset delta 192 * <p> 193 * Objects stored with this type actually have a different type which must 194 * be obtained from their delta base object. Delta objects store only the 195 * changes needed to apply to the base object in order to recover the 196 * original object. 197 * <p> 198 * An offset delta uses a negative offset from the start of this object to 199 * refer to its delta base. The base object must exist in this packfile 200 * (even in the case of a thin pack). 201 * <p> 202 * <b>This constant is fixed and is defined by the Git packfile format.</b> 203 */ 204 public static final int OBJ_OFS_DELTA = 6; 205 206 /** 207 * In-pack object type: reference delta 208 * <p> 209 * Objects stored with this type actually have a different type which must 210 * be obtained from their delta base object. Delta objects store only the 211 * changes needed to apply to the base object in order to recover the 212 * original object. 213 * <p> 214 * A reference delta uses a full object id (hash) to reference the delta 215 * base. The base object is allowed to be omitted from the packfile, but 216 * only in the case of a thin pack being transferred over the network. 217 * <p> 218 * <b>This constant is fixed and is defined by the Git packfile format.</b> 219 */ 220 public static final int OBJ_REF_DELTA = 7; 221 222 /** 223 * Pack file signature that occurs at file header - identifies file as Git 224 * packfile formatted. 225 * <p> 226 * <b>This constant is fixed and is defined by the Git packfile format.</b> 227 */ 228 public static final byte[] PACK_SIGNATURE = { 'P', 'A', 'C', 'K' }; 229 230 /** Native character encoding for commit messages, file names... */ 231 public static final Charset CHARSET; 232 233 /** Native character encoding for commit messages, file names... */ 234 public static final String CHARACTER_ENCODING; 235 236 /** Default main branch name */ 237 public static final String MASTER = "master"; 238 239 /** Default stash branch name */ 240 public static final String STASH = "stash"; 241 242 /** Prefix for branch refs */ 243 public static final String R_HEADS = "refs/heads/"; 244 245 /** Prefix for remotes refs */ 246 public static final String R_REMOTES = "refs/remotes/"; 247 248 /** Prefix for tag refs */ 249 public static final String R_TAGS = "refs/tags/"; 250 251 /** Prefix for notes refs */ 252 public static final String R_NOTES = "refs/notes/"; 253 254 /** Standard notes ref */ 255 public static final String R_NOTES_COMMITS = R_NOTES + "commits"; 256 257 /** Prefix for any ref */ 258 public static final String R_REFS = "refs/"; 259 260 /** Standard stash ref */ 261 public static final String R_STASH = R_REFS + STASH; 262 263 /** Logs folder name */ 264 public static final String LOGS = "logs"; 265 266 /** Info refs folder */ 267 public static final String INFO_REFS = "info/refs"; 268 269 /** Packed refs file */ 270 public static final String PACKED_REFS = "packed-refs"; 271 272 /** 273 * Excludes-file 274 * 275 * @since 3.0 276 */ 277 public static final String INFO_EXCLUDE = "info/exclude"; 278 279 /** 280 * Attributes-override-file 281 * 282 * @since 4.2 283 */ 284 public static final String INFO_ATTRIBUTES = "info/attributes"; 285 286 /** 287 * The system property that contains the system user name 288 * 289 * @since 3.6 290 */ 291 public static final String OS_USER_DIR = "user.dir"; 292 293 /** The system property that contains the system user name */ 294 public static final String OS_USER_NAME_KEY = "user.name"; 295 296 /** The environment variable that contains the author's name */ 297 public static final String GIT_AUTHOR_NAME_KEY = "GIT_AUTHOR_NAME"; 298 299 /** The environment variable that contains the author's email */ 300 public static final String GIT_AUTHOR_EMAIL_KEY = "GIT_AUTHOR_EMAIL"; 301 302 /** The environment variable that contains the commiter's name */ 303 public static final String GIT_COMMITTER_NAME_KEY = "GIT_COMMITTER_NAME"; 304 305 /** The environment variable that contains the commiter's email */ 306 public static final String GIT_COMMITTER_EMAIL_KEY = "GIT_COMMITTER_EMAIL"; 307 308 /** 309 * The environment variable that blocks use of the system config file 310 * 311 * @since 3.3 312 */ 313 public static final String GIT_CONFIG_NOSYSTEM_KEY = "GIT_CONFIG_NOSYSTEM"; 314 315 /** 316 * The environment variable that limits how close to the root of the file 317 * systems JGit will traverse when looking for a repository root. 318 */ 319 public static final String GIT_CEILING_DIRECTORIES_KEY = "GIT_CEILING_DIRECTORIES"; 320 321 /** 322 * The environment variable that tells us which directory is the ".git" 323 * directory 324 */ 325 public static final String GIT_DIR_KEY = "GIT_DIR"; 326 327 /** 328 * The environment variable that tells us which directory is the working 329 * directory. 330 */ 331 public static final String GIT_WORK_TREE_KEY = "GIT_WORK_TREE"; 332 333 /** 334 * The environment variable that tells us which file holds the Git index. 335 */ 336 public static final String GIT_INDEX_FILE_KEY = "GIT_INDEX_FILE"; 337 338 /** 339 * The environment variable that tells us where objects are stored 340 */ 341 public static final String GIT_OBJECT_DIRECTORY_KEY = "GIT_OBJECT_DIRECTORY"; 342 343 /** 344 * The environment variable that tells us where to look for objects, besides 345 * the default objects directory. 346 */ 347 public static final String GIT_ALTERNATE_OBJECT_DIRECTORIES_KEY = "GIT_ALTERNATE_OBJECT_DIRECTORIES"; 348 349 /** Default value for the user name if no other information is available */ 350 public static final String UNKNOWN_USER_DEFAULT = "unknown-user"; 351 352 /** Beginning of the common "Signed-off-by: " commit message line */ 353 public static final String SIGNED_OFF_BY_TAG = "Signed-off-by: "; 354 355 /** A gitignore file name */ 356 public static final String GITIGNORE_FILENAME = ".gitignore"; 357 358 /** Default remote name used by clone, push and fetch operations */ 359 public static final String DEFAULT_REMOTE_NAME = "origin"; 360 361 /** Default name for the Git repository directory */ 362 public static final String DOT_GIT = ".git"; 363 364 /** Default name for the Git repository configuration */ 365 public static final String CONFIG = "config"; 366 367 /** A bare repository typically ends with this string */ 368 public static final String DOT_GIT_EXT = ".git"; 369 370 /** 371 * Name of the attributes file 372 * 373 * @since 3.7 374 */ 375 public static final String DOT_GIT_ATTRIBUTES = ".gitattributes"; 376 377 /** 378 * Key for filters in .gitattributes 379 * 380 * @since 4.2 381 */ 382 public static final String ATTR_FILTER = "filter"; 383 384 /** 385 * clean command name, used to call filter driver 386 * 387 * @since 4.2 388 */ 389 public static final String ATTR_FILTER_TYPE_CLEAN = "clean"; 390 391 /** 392 * smudge command name, used to call filter driver 393 * 394 * @since 4.2 395 */ 396 public static final String ATTR_FILTER_TYPE_SMUDGE = "smudge"; 397 398 /** 399 * Builtin filter commands start with this prefix 400 * 401 * @since 4.6 402 */ 403 public static final String BUILTIN_FILTER_PREFIX = "jgit://builtin/"; 404 405 /** Name of the ignore file */ 406 public static final String DOT_GIT_IGNORE = ".gitignore"; 407 408 /** Name of the submodules file */ 409 public static final String DOT_GIT_MODULES = ".gitmodules"; 410 411 /** Name of the .git/shallow file */ 412 public static final String SHALLOW = "shallow"; 413 414 /** 415 * Prefix of the first line in a ".git" file 416 * 417 * @since 3.6 418 */ 419 public static final String GITDIR = "gitdir: "; 420 421 /** 422 * Name of the folder (inside gitDir) where submodules are stored 423 * 424 * @since 3.6 425 */ 426 public static final String MODULES = "modules"; 427 428 /** 429 * Name of the folder (inside gitDir) where the hooks are stored. 430 * 431 * @since 3.7 432 */ 433 public static final String HOOKS = "hooks"; 434 435 /** 436 * Merge attribute. 437 * 438 * @since 4.9 439 */ 440 public static final String ATTR_MERGE = "merge"; //$NON-NLS-1$ 441 442 /** 443 * Diff attribute. 444 * 445 * @since 4.11 446 */ 447 public static final String ATTR_DIFF = "diff"; //$NON-NLS-1$ 448 449 /** 450 * Binary value for custom merger. 451 * 452 * @since 4.9 453 */ 454 public static final String ATTR_BUILTIN_BINARY_MERGER = "binary"; //$NON-NLS-1$ 455 456 /** 457 * Create a new digest function for objects. 458 * 459 * @return a new digest object. 460 * @throws java.lang.RuntimeException 461 * this Java virtual machine does not support the required hash 462 * function. Very unlikely given that JGit uses a hash function 463 * that is in the Java reference specification. 464 */ 465 public static MessageDigest newMessageDigest() { 466 try { 467 return MessageDigest.getInstance(HASH_FUNCTION); 468 } catch (NoSuchAlgorithmException nsae) { 469 throw new RuntimeException(MessageFormat.format( 470 JGitText.get().requiredHashFunctionNotAvailable, HASH_FUNCTION), nsae); 471 } 472 } 473 474 /** 475 * Convert an OBJ_* type constant to a TYPE_* type constant. 476 * 477 * @param typeCode the type code, from a pack representation. 478 * @return the canonical string name of this type. 479 */ 480 public static String typeString(int typeCode) { 481 switch (typeCode) { 482 case OBJ_COMMIT: 483 return TYPE_COMMIT; 484 case OBJ_TREE: 485 return TYPE_TREE; 486 case OBJ_BLOB: 487 return TYPE_BLOB; 488 case OBJ_TAG: 489 return TYPE_TAG; 490 default: 491 throw new IllegalArgumentException(MessageFormat.format( 492 JGitText.get().badObjectType, Integer.valueOf(typeCode))); 493 } 494 } 495 496 /** 497 * Convert an OBJ_* type constant to an ASCII encoded string constant. 498 * <p> 499 * The ASCII encoded string is often the canonical representation of 500 * the type within a loose object header, or within a tag header. 501 * 502 * @param typeCode the type code, from a pack representation. 503 * @return the canonical ASCII encoded name of this type. 504 */ 505 public static byte[] encodedTypeString(int typeCode) { 506 switch (typeCode) { 507 case OBJ_COMMIT: 508 return ENCODED_TYPE_COMMIT; 509 case OBJ_TREE: 510 return ENCODED_TYPE_TREE; 511 case OBJ_BLOB: 512 return ENCODED_TYPE_BLOB; 513 case OBJ_TAG: 514 return ENCODED_TYPE_TAG; 515 default: 516 throw new IllegalArgumentException(MessageFormat.format( 517 JGitText.get().badObjectType, Integer.valueOf(typeCode))); 518 } 519 } 520 521 /** 522 * Parse an encoded type string into a type constant. 523 * 524 * @param id 525 * object id this type string came from; may be null if that is 526 * not known at the time the parse is occurring. 527 * @param typeString 528 * string version of the type code. 529 * @param endMark 530 * character immediately following the type string. Usually ' ' 531 * (space) or '\n' (line feed). 532 * @param offset 533 * position within <code>typeString</code> where the parse 534 * should start. Updated with the new position (just past 535 * <code>endMark</code> when the parse is successful. 536 * @return a type code constant (one of {@link #OBJ_BLOB}, 537 * {@link #OBJ_COMMIT}, {@link #OBJ_TAG}, {@link #OBJ_TREE}. 538 * @throws org.eclipse.jgit.errors.CorruptObjectException 539 * there is no valid type identified by <code>typeString</code>. 540 */ 541 public static int decodeTypeString(final AnyObjectId id, 542 final byte[] typeString, final byte endMark, 543 final MutableInteger offset) throws CorruptObjectException { 544 try { 545 int position = offset.value; 546 switch (typeString[position]) { 547 case 'b': 548 if (typeString[position + 1] != 'l' 549 || typeString[position + 2] != 'o' 550 || typeString[position + 3] != 'b' 551 || typeString[position + 4] != endMark) 552 throw new CorruptObjectException(id, JGitText.get().corruptObjectInvalidType); 553 offset.value = position + 5; 554 return Constants.OBJ_BLOB; 555 556 case 'c': 557 if (typeString[position + 1] != 'o' 558 || typeString[position + 2] != 'm' 559 || typeString[position + 3] != 'm' 560 || typeString[position + 4] != 'i' 561 || typeString[position + 5] != 't' 562 || typeString[position + 6] != endMark) 563 throw new CorruptObjectException(id, JGitText.get().corruptObjectInvalidType); 564 offset.value = position + 7; 565 return Constants.OBJ_COMMIT; 566 567 case 't': 568 switch (typeString[position + 1]) { 569 case 'a': 570 if (typeString[position + 2] != 'g' 571 || typeString[position + 3] != endMark) 572 throw new CorruptObjectException(id, JGitText.get().corruptObjectInvalidType); 573 offset.value = position + 4; 574 return Constants.OBJ_TAG; 575 576 case 'r': 577 if (typeString[position + 2] != 'e' 578 || typeString[position + 3] != 'e' 579 || typeString[position + 4] != endMark) 580 throw new CorruptObjectException(id, JGitText.get().corruptObjectInvalidType); 581 offset.value = position + 5; 582 return Constants.OBJ_TREE; 583 584 default: 585 throw new CorruptObjectException(id, JGitText.get().corruptObjectInvalidType); 586 } 587 588 default: 589 throw new CorruptObjectException(id, JGitText.get().corruptObjectInvalidType); 590 } 591 } catch (ArrayIndexOutOfBoundsException bad) { 592 throw new CorruptObjectException(id, JGitText.get().corruptObjectInvalidType); 593 } 594 } 595 596 /** 597 * Convert an integer into its decimal representation. 598 * 599 * @param s 600 * the integer to convert. 601 * @return a decimal representation of the input integer. The returned array 602 * is the smallest array that will hold the value. 603 */ 604 public static byte[] encodeASCII(long s) { 605 return encodeASCII(Long.toString(s)); 606 } 607 608 /** 609 * Convert a string to US-ASCII encoding. 610 * 611 * @param s 612 * the string to convert. Must not contain any characters over 613 * 127 (outside of 7-bit ASCII). 614 * @return a byte array of the same length as the input string, holding the 615 * same characters, in the same order. 616 * @throws java.lang.IllegalArgumentException 617 * the input string contains one or more characters outside of 618 * the 7-bit ASCII character space. 619 */ 620 public static byte[] encodeASCII(String s) { 621 final byte[] r = new byte[s.length()]; 622 for (int k = r.length - 1; k >= 0; k--) { 623 final char c = s.charAt(k); 624 if (c > 127) 625 throw new IllegalArgumentException(MessageFormat.format(JGitText.get().notASCIIString, s)); 626 r[k] = (byte) c; 627 } 628 return r; 629 } 630 631 /** 632 * Convert a string to a byte array in the standard character encoding. 633 * 634 * @param str 635 * the string to convert. May contain any Unicode characters. 636 * @return a byte array representing the requested string, encoded using the 637 * default character encoding (UTF-8). 638 * @see #CHARACTER_ENCODING 639 */ 640 public static byte[] encode(String str) { 641 final ByteBuffer bb = Constants.CHARSET.encode(str); 642 final int len = bb.limit(); 643 if (bb.hasArray() && bb.arrayOffset() == 0) { 644 final byte[] arr = bb.array(); 645 if (arr.length == len) 646 return arr; 647 } 648 649 final byte[] arr = new byte[len]; 650 bb.get(arr); 651 return arr; 652 } 653 654 static { 655 if (OBJECT_ID_LENGTH != newMessageDigest().getDigestLength()) 656 throw new LinkageError(JGitText.get().incorrectOBJECT_ID_LENGTH); 657 CHARSET = UTF_8; 658 CHARACTER_ENCODING = CHARSET.name(); 659 } 660 661 /** name of the file containing the commit msg for a merge commit */ 662 public static final String MERGE_MSG = "MERGE_MSG"; 663 664 /** name of the file containing the IDs of the parents of a merge commit */ 665 public static final String MERGE_HEAD = "MERGE_HEAD"; 666 667 /** name of the file containing the ID of a cherry pick commit in case of conflicts */ 668 public static final String CHERRY_PICK_HEAD = "CHERRY_PICK_HEAD"; 669 670 /** name of the file containing the commit msg for a squash commit */ 671 public static final String SQUASH_MSG = "SQUASH_MSG"; 672 673 /** name of the file containing the ID of a revert commit in case of conflicts */ 674 public static final String REVERT_HEAD = "REVERT_HEAD"; 675 676 /** 677 * name of the ref ORIG_HEAD used by certain commands to store the original 678 * value of HEAD 679 */ 680 public static final String ORIG_HEAD = "ORIG_HEAD"; 681 682 /** 683 * Name of the file in which git commands and hooks store and read the 684 * message prepared for the upcoming commit. 685 * 686 * @since 4.0 687 */ 688 public static final String COMMIT_EDITMSG = "COMMIT_EDITMSG"; 689 690 /** objectid for the empty blob */ 691 public static final ObjectId EMPTY_BLOB_ID = ObjectId 692 .fromString("e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"); 693 694 /** 695 * Suffix of lock file name 696 * 697 * @since 5.0 698 */ 699 public static final String LOCK_SUFFIX = ".lock"; //$NON-NLS-1$ 700 701 private Constants() { 702 // Hide the default constructor 703 } 704 }