1 page.title=Dalvik Executable Format 2 @jd:body 3 4 <!-- 5 Copyright 2013 The Android Open Source Project 6 7 Licensed under the Apache License, Version 2.0 (the "License"); 8 you may not use this file except in compliance with the License. 9 You may obtain a copy of the License at 10 11 http://www.apache.org/licenses/LICENSE-2.0 12 13 Unless required by applicable law or agreed to in writing, software 14 distributed under the License is distributed on an "AS IS" BASIS, 15 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 16 See the License for the specific language governing permissions and 17 limitations under the License. 18 --> 19 <p>This document describes the layout and contents of <code>.dex</code> 20 files, which are used to hold a set of class definitions and their associated 21 adjunct data.</p> 22 23 <h2>Guide To Types</h2> 24 25 <table class="guide"> 26 <thead> 27 <tr> 28 <th>Name</th> 29 <th>Description</th> 30 </tr> 31 </thead> 32 <tbody> 33 <tr> 34 <td>byte</td> 35 <td>8-bit signed int</td> 36 </tr> 37 <tr> 38 <td>ubyte</td> 39 <td>8-bit unsigned int</td> 40 </tr> 41 <tr> 42 <td>short</td> 43 <td>16-bit signed int, little-endian</td> 44 </tr> 45 <tr> 46 <td>ushort</td> 47 <td>16-bit unsigned int, little-endian</td> 48 </tr> 49 <tr> 50 <td>int</td> 51 <td>32-bit signed int, little-endian</td> 52 </tr> 53 <tr> 54 <td>uint</td> 55 <td>32-bit unsigned int, little-endian</td> 56 </tr> 57 <tr> 58 <td>long</td> 59 <td>64-bit signed int, little-endian</td> 60 </tr> 61 <tr> 62 <td>ulong</td> 63 <td>64-bit unsigned int, little-endian</td> 64 </tr> 65 <tr> 66 <td>sleb128</td> 67 <td>signed LEB128, variable-length (see below)</td> 68 </tr> 69 <tr> 70 <td>uleb128</td> 71 <td>unsigned LEB128, variable-length (see below)</td> 72 </tr> 73 <tr> 74 <td>uleb128p1</td> 75 <td>unsigned LEB128 plus <code>1</code>, variable-length (see below)</td> 76 </tr> 77 </tbody> 78 </table> 79 80 <h3>LEB128</h3> 81 82 <p>LEB128 ("<b>L</b>ittle-<b>E</b>ndian <b>B</b>ase <b>128</b>") is a 83 variable-length encoding for 84 arbitrary signed or unsigned integer quantities. The format was 85 borrowed from the <a href="http://dwarfstd.org/Dwarf3Std.php">DWARF3</a> 86 specification. In a <code>.dex</code> file, LEB128 is only ever used to 87 encode 32-bit quantities.</p> 88 89 <p>Each LEB128 encoded value consists of one to five 90 bytes, which together represent a single 32-bit value. Each 91 byte has its most significant bit set except for the final byte in the 92 sequence, which has its most significant bit clear. The remaining 93 seven bits of each byte are payload, with the least significant seven 94 bits of the quantity in the first byte, the next seven in the second 95 byte and so on. In the case of a signed LEB128 (<code>sleb128</code>), 96 the most significant payload bit of the final byte in the sequence is 97 sign-extended to produce the final value. In the unsigned case 98 (<code>uleb128</code>), any bits not explicitly represented are 99 interpreted as <code>0</code>. 100 101 <table class="leb128Bits"> 102 <thead> 103 <tr><th colspan="16">Bitwise diagram of a two-byte LEB128 value</th></tr> 104 <tr> 105 <th colspan="8">First byte</td> 106 <th colspan="8">Second byte</td> 107 </tr> 108 </thead> 109 <tbody> 110 <tr> 111 <td class="start1"><code>1</code></td> 112 <td>bit<sub>6</sub></td> 113 <td>bit<sub>5</sub></td> 114 <td>bit<sub>4</sub></td> 115 <td>bit<sub>3</sub></td> 116 <td>bit<sub>2</sub></td> 117 <td>bit<sub>1</sub></td> 118 <td>bit<sub>0</sub></td> 119 <td class="start2"><code>0</code></td> 120 <td>bit<sub>13</sub></td> 121 <td>bit<sub>12</sub></td> 122 <td>bit<sub>11</sub></td> 123 <td>bit<sub>10</sub></td> 124 <td>bit<sub>9</sub></td> 125 <td>bit<sub>8</sub></td> 126 <td class="end2">bit<sub>7</sub></td> 127 </tr> 128 </tbody> 129 </table> 130 131 <p>The variant <code>uleb128p1</code> is used to represent a signed 132 value, where the representation is of the value <i>plus one</i> encoded 133 as a <code>uleb128</code>. This makes the encoding of <code>-1</code> 134 (alternatively thought of as the unsigned value <code>0xffffffff</code>) 135 — but no other negative number — a single byte, and is 136 useful in exactly those cases where the represented number must either 137 be non-negative or <code>-1</code> (or <code>0xffffffff</code>), 138 and where no other negative values are allowed (or where large unsigned 139 values are unlikely to be needed).</p> 140 141 <p>Here are some examples of the formats:</p> 142 143 <table class="leb128"> 144 <thead> 145 <tr> 146 <th>Encoded Sequence</th> 147 <th>As <code>sleb128</code></th> 148 <th>As <code>uleb128</code></th> 149 <th>As <code>uleb128p1</code></th> 150 </tr> 151 </thead> 152 <tbody> 153 <tr><td>00</td><td>0</td><td>0</td><td>-1</td></tr> 154 <tr><td>01</td><td>1</td><td>1</td><td>0</td></tr> 155 <tr><td>7f</td><td>-1</td><td>127</td><td>126</td></tr> 156 <tr><td>80 7f</td><td>-128</td><td>16256</td><td>16255</td></tr> 157 </tbody> 158 </table> 159 160 <h2>Overall File Layout</h2> 161 162 <table class="format"> 163 <thead> 164 <tr> 165 <th>Name</th> 166 <th>Format</th> 167 <th>Description</th> 168 </tr> 169 </thead> 170 <tbody> 171 <tr> 172 <td>header</td> 173 <td>header_item</td> 174 <td>the header</td> 175 </tr> 176 <tr> 177 <td>string_ids</td> 178 <td>string_id_item[]</td> 179 <td>string identifiers list. These are identifiers for all the strings 180 used by this file, either for internal naming (e.g., type descriptors) 181 or as constant objects referred to by code. This list must be sorted 182 by string contents, using UTF-16 code point values (not in a 183 locale-sensitive manner), and it must not contain any duplicate entries. 184 </td> 185 </tr> 186 <tr> 187 <td>type_ids</td> 188 <td>type_id_item[]</td> 189 <td>type identifiers list. These are identifiers for all types (classes, 190 arrays, or primitive types) referred to by this file, whether defined 191 in the file or not. This list must be sorted by <code>string_id</code> 192 index, and it must not contain any duplicate entries. 193 </td> 194 </tr> 195 <tr> 196 <td>proto_ids</td> 197 <td>proto_id_item[]</td> 198 <td>method prototype identifiers list. These are identifiers for all 199 prototypes referred to by this file. This list must be sorted in 200 return-type (by <code>type_id</code> index) major order, and then 201 by arguments (also by <code>type_id</code> index). The list must not 202 contain any duplicate entries. 203 </td> 204 </tr> 205 <tr> 206 <td>field_ids</td> 207 <td>field_id_item[]</td> 208 <td>field identifiers list. These are identifiers for all fields 209 referred to by this file, whether defined in the file or not. This 210 list must be sorted, where the defining type (by <code>type_id</code> 211 index) is the major order, field name (by <code>string_id</code> index) 212 is the intermediate order, and type (by <code>type_id</code> index) 213 is the minor order. The list must not contain any duplicate entries. 214 </td> 215 </tr> 216 <tr> 217 <td>method_ids</td> 218 <td>method_id_item[]</td> 219 <td>method identifiers list. These are identifiers for all methods 220 referred to by this file, whether defined in the file or not. This 221 list must be sorted, where the defining type (by <code>type_id</code> 222 index) is the major order, method name (by <code>string_id</code> 223 index) is the intermediate order, and method prototype (by 224 <code>proto_id</code> index) is the minor order. The list must not 225 contain any duplicate entries. 226 </td> 227 </tr> 228 <tr> 229 <td>class_defs</td> 230 <td>class_def_item[]</td> 231 <td>class definitions list. The classes must be ordered such that a given 232 class's superclass and implemented interfaces appear in the 233 list earlier than the referring class. Furthermore, it is invalid for 234 a definition for the same-named class to appear more than once in 235 the list. 236 </td> 237 </tr> 238 <tr> 239 <td>data</td> 240 <td>ubyte[]</td> 241 <td>data area, containing all the support data for the tables listed above. 242 Different items have different alignment requirements, and 243 padding bytes are inserted before each item if necessary to achieve 244 proper alignment. 245 </td> 246 </tr> 247 <tr> 248 <td>link_data</td> 249 <td>ubyte[]</td> 250 <td>data used in statically linked files. The format of the data in 251 this section is left unspecified by this document. 252 This section is empty in unlinked files, and runtime implementations 253 may use it as they see fit. 254 </td> 255 </tr> 256 </tbody> 257 </table> 258 259 <h2>Bitfield, String, and Constant Definitions</h2> 260 261 <h3>DEX_FILE_MAGIC</h3> 262 <h4>embedded in header_item</h4> 263 264 <p>The constant array/string <code>DEX_FILE_MAGIC</code> is the list of 265 bytes that must appear at the beginning of a <code>.dex</code> file 266 in order for it to be recognized as such. The value intentionally 267 contains a newline (<code>"\n"</code> or <code>0x0a</code>) and a 268 null byte (<code>"\0"</code> or <code>0x00</code>) in order to help 269 in the detection of certain forms of corruption. The value also 270 encodes a format version number as three decimal digits, which is 271 expected to increase monotonically over time as the format evolves.</p> 272 273 <pre> 274 ubyte[8] DEX_FILE_MAGIC = { 0x64 0x65 0x78 0x0a 0x30 0x33 0x35 0x00 } 275 = "dex\n035\0" 276 </pre> 277 278 <p><b>Note:</b> At least a couple earlier versions of the format have 279 been used in widely-available public software releases. For example, 280 version <code>009</code> was used for the M3 releases of the 281 Android platform (November–December 2007), 282 and version <code>013</code> was used for the M5 releases of the Android 283 platform (February–March 2008). In several respects, these earlier 284 versions of the format differ significantly from the version described in this 285 document.</p> 286 287 <h3>ENDIAN_CONSTANT and REVERSE_ENDIAN_CONSTANT</h3> 288 <h4>embedded in header_item</h4> 289 290 <p>The constant <code>ENDIAN_CONSTANT</code> is used to indicate the 291 endianness of the file in which it is found. Although the standard 292 <code>.dex</code> format is little-endian, implementations may choose 293 to perform byte-swapping. Should an implementation come across a 294 header whose <code>endian_tag</code> is <code>REVERSE_ENDIAN_CONSTANT</code> 295 instead of <code>ENDIAN_CONSTANT</code>, it would know that the file 296 has been byte-swapped from the expected form.</p> 297 298 <pre> 299 uint ENDIAN_CONSTANT = 0x12345678; 300 uint REVERSE_ENDIAN_CONSTANT = 0x78563412; 301 </pre> 302 303 <h3>NO_INDEX</h3> 304 <h4>embedded in class_def_item and debug_info_item</h4> 305 306 <p>The constant <code>NO_INDEX</code> is used to indicate that 307 an index value is absent.</p> 308 309 <p><b>Note:</b> This value isn't defined to be 310 <code>0</code>, because that is in fact typically a valid index.</p> 311 312 <p><b>Also Note:</b> The chosen value for <code>NO_INDEX</code> is 313 representable as a single byte in the <code>uleb128p1</code> encoding.</p> 314 315 <pre> 316 uint NO_INDEX = 0xffffffff; // == -1 if treated as a signed int 317 </pre> 318 319 <h3>access_flags Definitions</h3> 320 <h4>embedded in class_def_item, encoded_field, encoded_method, and 321 InnerClass</h4> 322 323 <p>Bitfields of these flags are used to indicate the accessibility and 324 overall properties of classes and class members.</p> 325 326 <table class="accessFlags"> 327 <thead> 328 <tr> 329 <th>Name</th> 330 <th>Value</th> 331 <th>For Classes (and <code>InnerClass</code> annotations)</th> 332 <th>For Fields</th> 333 <th>For Methods</th> 334 </tr> 335 </thead> 336 <tbody> 337 <tr> 338 <td>ACC_PUBLIC</td> 339 <td>0x1</td> 340 <td><code>public</code>: visible everywhere</td> 341 <td><code>public</code>: visible everywhere</td> 342 <td><code>public</code>: visible everywhere</td> 343 </tr> 344 <tr> 345 <td>ACC_PRIVATE</td> 346 <td>0x2</td> 347 <td><super>*</super> 348 <code>private</code>: only visible to defining class 349 </td> 350 <td><code>private</code>: only visible to defining class</td> 351 <td><code>private</code>: only visible to defining class</td> 352 </tr> 353 <tr> 354 <td>ACC_PROTECTED</td> 355 <td>0x4</td> 356 <td><super>*</super> 357 <code>protected</code>: visible to package and subclasses 358 </td> 359 <td><code>protected</code>: visible to package and subclasses</td> 360 <td><code>protected</code>: visible to package and subclasses</td> 361 </tr> 362 <tr> 363 <td>ACC_STATIC</td> 364 <td>0x8</td> 365 <td><super>*</super> 366 <code>static</code>: is not constructed with an outer 367 <code>this</code> reference</td> 368 <td><code>static</code>: global to defining class</td> 369 <td><code>static</code>: does not take a <code>this</code> argument</td> 370 </tr> 371 <tr> 372 <td>ACC_FINAL</td> 373 <td>0x10</td> 374 <td><code>final</code>: not subclassable</td> 375 <td><code>final</code>: immutable after construction</td> 376 <td><code>final</code>: not overridable</td> 377 </tr> 378 <tr> 379 <td>ACC_SYNCHRONIZED</td> 380 <td>0x20</td> 381 <td> </td> 382 <td> </td> 383 <td><code>synchronized</code>: associated lock automatically acquired 384 around call to this method. <b>Note:</b> This is only valid to set when 385 <code>ACC_NATIVE</code> is also set.</td> 386 </tr> 387 <tr> 388 <td>ACC_VOLATILE</td> 389 <td>0x40</td> 390 <td> </td> 391 <td><code>volatile</code>: special access rules to help with thread 392 safety</td> 393 <td> </td> 394 </tr> 395 <tr> 396 <td>ACC_BRIDGE</td> 397 <td>0x40</td> 398 <td> </td> 399 <td> </td> 400 <td>bridge method, added automatically by compiler as a type-safe 401 bridge</td> 402 </tr> 403 <tr> 404 <td>ACC_TRANSIENT</td> 405 <td>0x80</td> 406 <td> </td> 407 <td><code>transient</code>: not to be saved by default serialization</td> 408 <td> </td> 409 </tr> 410 <tr> 411 <td>ACC_VARARGS</td> 412 <td>0x80</td> 413 <td> </td> 414 <td> </td> 415 <td>last argument should be treated as a "rest" argument by compiler</td> 416 </tr> 417 <tr> 418 <td>ACC_NATIVE</td> 419 <td>0x100</td> 420 <td> </td> 421 <td> </td> 422 <td><code>native</code>: implemented in native code</td> 423 </tr> 424 <tr> 425 <td>ACC_INTERFACE</td> 426 <td>0x200</td> 427 <td><code>interface</code>: multiply-implementable abstract class</td> 428 <td> </td> 429 <td> </td> 430 </tr> 431 <tr> 432 <td>ACC_ABSTRACT</td> 433 <td>0x400</td> 434 <td><code>abstract</code>: not directly instantiable</td> 435 <td> </td> 436 <td><code>abstract</code>: unimplemented by this class</td> 437 </tr> 438 <tr> 439 <td>ACC_STRICT</td> 440 <td>0x800</td> 441 <td> </td> 442 <td> </td> 443 <td><code>strictfp</code>: strict rules for floating-point arithmetic</td> 444 </tr> 445 <tr> 446 <td>ACC_SYNTHETIC</td> 447 <td>0x1000</td> 448 <td>not directly defined in source code</td> 449 <td>not directly defined in source code</td> 450 <td>not directly defined in source code</td> 451 </tr> 452 <tr> 453 <td>ACC_ANNOTATION</td> 454 <td>0x2000</td> 455 <td>declared as an annotation class</td> 456 <td> </td> 457 <td> </td> 458 </tr> 459 <tr> 460 <td>ACC_ENUM</td> 461 <td>0x4000</td> 462 <td>declared as an enumerated type</td> 463 <td>declared as an enumerated value</td> 464 <td> </td> 465 </tr> 466 <tr> 467 <td><i>(unused)</i></td> 468 <td>0x8000</td> 469 <td> </td> 470 <td> </td> 471 <td> </td> 472 </tr> 473 <tr> 474 <td>ACC_CONSTRUCTOR</td> 475 <td>0x10000</td> 476 <td> </td> 477 <td> </td> 478 <td>constructor method (class or instance initializer)</td> 479 </tr> 480 <tr> 481 <td>ACC_DECLARED_<br/>SYNCHRONIZED</td> 482 <td>0x20000</td> 483 <td> </td> 484 <td> </td> 485 <td>declared <code>synchronized</code>. <b>Note:</b> This has no effect on 486 execution (other than in reflection of this flag, per se). 487 </td> 488 </tr> 489 </tbody> 490 </table> 491 492 <p><super>*</super> Only allowed on for <code>InnerClass</code> annotations, 493 and must not ever be on in a <code>class_def_item</code>.</p> 494 495 <h3>MUTF-8 (Modified UTF-8) Encoding</h3> 496 497 <p>As a concession to easier legacy support, the <code>.dex</code> format 498 encodes its string data in a de facto standard modified UTF-8 form, hereafter 499 referred to as MUTF-8. This form is identical to standard UTF-8, except:</p> 500 501 <ul> 502 <li>Only the one-, two-, and three-byte encodings are used.</li> 503 <li>Code points in the range <code>U+10000</code> … 504 <code>U+10ffff</code> are encoded as a surrogate pair, each of 505 which is represented as a three-byte encoded value.</li> 506 <li>The code point <code>U+0000</code> is encoded in two-byte form.</li> 507 <li>A plain null byte (value <code>0</code>) indicates the end of 508 a string, as is the standard C language interpretation.</li> 509 </ul> 510 511 <p>The first two items above can be summarized as: MUTF-8 512 is an encoding format for UTF-16, instead of being a more direct 513 encoding format for Unicode characters.</p> 514 515 <p>The final two items above make it simultaneously possible to include 516 the code point <code>U+0000</code> in a string <i>and</i> still manipulate 517 it as a C-style null-terminated string.</p> 518 519 <p>However, the special encoding of <code>U+0000</code> means that, unlike 520 normal UTF-8, the result of calling the standard C function 521 <code>strcmp()</code> on a pair of MUTF-8 strings does not always 522 indicate the properly signed result of comparison of <i>unequal</i> strings. 523 When ordering (not just equality) is a concern, the most straightforward 524 way to compare MUTF-8 strings is to decode them character by character, 525 and compare the decoded values. (However, more clever implementations are 526 also possible.)</p> 527 528 <p>Please refer to <a href="http://unicode.org">The Unicode 529 Standard</a> for further information about character encoding. 530 MUTF-8 is actually closer to the (relatively less well-known) encoding 531 <a href="http://www.unicode.org/reports/tr26/">CESU-8</a> than to UTF-8 532 per se.</p> 533 534 <h3>encoded_value Encoding</h3> 535 <h4>embedded in annotation_element and encoded_array_item </h4> 536 537 <p>An <code>encoded_value</code> is an encoded piece of (nearly) 538 arbitrary hierarchically structured data. The encoding is meant to 539 be both compact and straightforward to parse.</p> 540 541 <table class="format"> 542 <thead> 543 <tr> 544 <th>Name</th> 545 <th>Format</th> 546 <th>Description</th> 547 </tr> 548 </thead> 549 <tbody> 550 <tr> 551 <td>(value_arg << 5) | value_type</td> 552 <td>ubyte</td> 553 <td>byte indicating the type of the immediately subsequent 554 <code>value</code> along 555 with an optional clarifying argument in the high-order three bits. 556 See below for the various <code>value</code> definitions. 557 In most cases, <code>value_arg</code> encodes the length of 558 the immediately-subsequent <code>value</code> in bytes, as 559 <code>(size - 1)</code>, e.g., <code>0</code> means that 560 the value requires one byte, and <code>7</code> means it requires 561 eight bytes; however, there are exceptions as noted below. 562 </td> 563 </tr> 564 <tr> 565 <td>value</td> 566 <td>ubyte[]</td> 567 <td>bytes representing the value, variable in length and interpreted 568 differently for different <code>value_type</code> bytes, though 569 always little-endian. See the various value definitions below for 570 details. 571 </td> 572 </tr> 573 </tbody> 574 </table> 575 576 <h3>Value Formats</h3> 577 578 <table class="encodedValue"> 579 <thead> 580 <tr> 581 <th>Type Name</th> 582 <th><code>value_type</code></th> 583 <th><code>value_arg</code> Format</th> 584 <th><code>value</code> Format</th> 585 <th>Description</th> 586 </tr> 587 </thead> 588 <tbody> 589 <tr> 590 <td>VALUE_BYTE</td> 591 <td>0x00</td> 592 <td><i>(none; must be <code>0</code>)</i></td> 593 <td>ubyte[1]</td> 594 <td>signed one-byte integer value</td> 595 </tr> 596 <tr> 597 <td>VALUE_SHORT</td> 598 <td>0x02</td> 599 <td>size - 1 (0…1)</td> 600 <td>ubyte[size]</td> 601 <td>signed two-byte integer value, sign-extended</td> 602 </tr> 603 <tr> 604 <td>VALUE_CHAR</td> 605 <td>0x03</td> 606 <td>size - 1 (0…1)</td> 607 <td>ubyte[size]</td> 608 <td>unsigned two-byte integer value, zero-extended</td> 609 </tr> 610 <tr> 611 <td>VALUE_INT</td> 612 <td>0x04</td> 613 <td>size - 1 (0…3)</td> 614 <td>ubyte[size]</td> 615 <td>signed four-byte integer value, sign-extended</td> 616 </tr> 617 <tr> 618 <td>VALUE_LONG</td> 619 <td>0x06</td> 620 <td>size - 1 (0…7)</td> 621 <td>ubyte[size]</td> 622 <td>signed eight-byte integer value, sign-extended</td> 623 </tr> 624 <tr> 625 <td>VALUE_FLOAT</td> 626 <td>0x10</td> 627 <td>size - 1 (0…3)</td> 628 <td>ubyte[size]</td> 629 <td>four-byte bit pattern, zero-extended <i>to the right</i>, and 630 interpreted as an IEEE754 32-bit floating point value 631 </td> 632 </tr> 633 <tr> 634 <td>VALUE_DOUBLE</td> 635 <td>0x11</td> 636 <td>size - 1 (0…7)</td> 637 <td>ubyte[size]</td> 638 <td>eight-byte bit pattern, zero-extended <i>to the right</i>, and 639 interpreted as an IEEE754 64-bit floating point value 640 </td> 641 </tr> 642 <tr> 643 <td>VALUE_STRING</td> 644 <td>0x17</td> 645 <td>size - 1 (0…3)</td> 646 <td>ubyte[size]</td> 647 <td>unsigned (zero-extended) four-byte integer value, 648 interpreted as an index into 649 the <code>string_ids</code> section and representing a string value 650 </td> 651 </tr> 652 <tr> 653 <td>VALUE_TYPE</td> 654 <td>0x18</td> 655 <td>size - 1 (0…3)</td> 656 <td>ubyte[size]</td> 657 <td>unsigned (zero-extended) four-byte integer value, 658 interpreted as an index into 659 the <code>type_ids</code> section and representing a reflective 660 type/class value 661 </td> 662 </tr> 663 <tr> 664 <td>VALUE_FIELD</td> 665 <td>0x19</td> 666 <td>size - 1 (0…3)</td> 667 <td>ubyte[size]</td> 668 <td>unsigned (zero-extended) four-byte integer value, 669 interpreted as an index into 670 the <code>field_ids</code> section and representing a reflective 671 field value 672 </td> 673 </tr> 674 <tr> 675 <td>VALUE_METHOD</td> 676 <td>0x1a</td> 677 <td>size - 1 (0…3)</td> 678 <td>ubyte[size]</td> 679 <td>unsigned (zero-extended) four-byte integer value, 680 interpreted as an index into 681 the <code>method_ids</code> section and representing a reflective 682 method value 683 </td> 684 </tr> 685 <tr> 686 <td>VALUE_ENUM</td> 687 <td>0x1b</td> 688 <td>size - 1 (0…3)</td> 689 <td>ubyte[size]</td> 690 <td>unsigned (zero-extended) four-byte integer value, 691 interpreted as an index into 692 the <code>field_ids</code> section and representing the value of 693 an enumerated type constant 694 </td> 695 </tr> 696 <tr> 697 <td>VALUE_ARRAY</td> 698 <td>0x1c</td> 699 <td><i>(none; must be <code>0</code>)</i></td> 700 <td>encoded_array</td> 701 <td>an array of values, in the format specified by 702 "<code>encoded_array</code> Format" below. The size 703 of the <code>value</code> is implicit in the encoding. 704 </td> 705 </tr> 706 <tr> 707 <td>VALUE_ANNOTATION</td> 708 <td>0x1d</td> 709 <td><i>(none; must be <code>0</code>)</i></td> 710 <td>encoded_annotation</td> 711 <td>a sub-annotation, in the format specified by 712 "<code>encoded_annotation</code> Format" below. The size 713 of the <code>value</code> is implicit in the encoding. 714 </td> 715 </tr> 716 <tr> 717 <td>VALUE_NULL</td> 718 <td>0x1e</td> 719 <td><i>(none; must be <code>0</code>)</i></td> 720 <td><i>(none)</i></td> 721 <td><code>null</code> reference value</td> 722 </tr> 723 <tr> 724 <td>VALUE_BOOLEAN</td> 725 <td>0x1f</td> 726 <td>boolean (0…1)</td> 727 <td><i>(none)</i></td> 728 <td>one-bit value; <code>0</code> for <code>false</code> and 729 <code>1</code> for <code>true</code>. The bit is represented in the 730 <code>value_arg</code>. 731 </td> 732 </tr> 733 </tbody> 734 </table> 735 736 <h3>encoded_array Format</h3> 737 738 <table class="format"> 739 <thead> 740 <tr> 741 <th>Name</th> 742 <th>Format</th> 743 <th>Description</th> 744 </tr> 745 </thead> 746 <tbody> 747 <tr> 748 <td>size</td> 749 <td>uleb128</td> 750 <td>number of elements in the array</td> 751 </tr> 752 <tr> 753 <td>values</td> 754 <td>encoded_value[size]</td> 755 <td>a series of <code>size</code> <code>encoded_value</code> byte 756 sequences in the format specified by this section, concatenated 757 sequentially. 758 </td> 759 </tr> 760 </tbody> 761 </table> 762 763 <h3>encoded_annotation Format</h3> 764 765 <table class="format"> 766 <thead> 767 <tr> 768 <th>Name</th> 769 <th>Format</th> 770 <th>Description</th> 771 </tr> 772 </thead> 773 <tbody> 774 <tr> 775 <td>type_idx</td> 776 <td>uleb128</td> 777 <td>type of the annotation. This must be a class (not array or primitive) 778 type. 779 </td> 780 </tr> 781 <tr> 782 <td>size</td> 783 <td>uleb128</td> 784 <td>number of name-value mappings in this annotation</td> 785 </tr> 786 <tr> 787 <td>elements</td> 788 <td>annotation_element[size]</td> 789 <td>elements of the annotataion, represented directly in-line (not as 790 offsets). Elements must be sorted in increasing order by 791 <code>string_id</code> index. 792 </td> 793 </tr> 794 </tbody> 795 </table> 796 797 <h3>annotation_element Format</h3> 798 799 <table class="format"> 800 <thead> 801 <tr> 802 <th>Name</th> 803 <th>Format</th> 804 <th>Description</th> 805 </tr> 806 </thead> 807 <tbody> 808 <tr> 809 <td>name_idx</td> 810 <td>uleb128</td> 811 <td>element name, represented as an index into the 812 <code>string_ids</code> section. The string must conform to the 813 syntax for <i>MemberName</i>, defined above. 814 </td> 815 </tr> 816 <tr> 817 <td>value</td> 818 <td>encoded_value</td> 819 <td>element value</td> 820 </tr> 821 </tbody> 822 </table> 823 824 <h2>String Syntax</h2> 825 826 <p>There are several kinds of item in a <code>.dex</code> file which 827 ultimately refer to a string. The following BNF-style definitions 828 indicate the acceptable syntax for these strings.</p> 829 830 <h3><i>SimpleName</i></h3> 831 832 <p>A <i>SimpleName</i> is the basis for the syntax of the names of other 833 things. The <code>.dex</code> format allows a fair amount of latitude 834 here (much more than most common source languages). In brief, a simple 835 name consists of any low-ASCII alphabetic character or digit, a few 836 specific low-ASCII symbols, and most non-ASCII code points that are not 837 control, space, or special characters. Note that surrogate code points 838 (in the range <code>U+d800</code> … <code>U+dfff</code>) are not 839 considered valid name characters, per se, but Unicode supplemental 840 characters <i>are</i> valid (which are represented by the final 841 alternative of the rule for <i>SimpleNameChar</i>), and they should be 842 represented in a file as pairs of surrogate code points in the MUTF-8 843 encoding.</p> 844 845 <table class="bnf"> 846 <tr><td colspan="2" class="def"><i>SimpleName</i> →</td></tr> 847 <tr> 848 <td/> 849 <td><i>SimpleNameChar</i> (<i>SimpleNameChar</i>)*</td> 850 </tr> 851 852 <tr><td colspan="2" class="def"><i>SimpleNameChar</i> →</td></tr> 853 <tr> 854 <td/> 855 <td><code>'A'</code> … <code>'Z'</code></td> 856 </tr> 857 <tr> 858 <td class="bar">|</td> 859 <td><code>'a'</code> … <code>'z'</code></td> 860 </tr> 861 <tr> 862 <td class="bar">|</td> 863 <td><code>'0'</code> … <code>'9'</code></td> 864 </tr> 865 <tr> 866 <td class="bar">|</td> 867 <td><code>'$'</code></td> 868 </tr> 869 <tr> 870 <td class="bar">|</td> 871 <td><code>'-'</code></td> 872 </tr> 873 <tr> 874 <td class="bar">|</td> 875 <td><code>'_'</code></td> 876 </tr> 877 <tr> 878 <td class="bar">|</td> 879 <td><code>U+00a1</code> … <code>U+1fff</code></td> 880 </tr> 881 <tr> 882 <td class="bar">|</td> 883 <td><code>U+2010</code> … <code>U+2027</code></td> 884 </tr> 885 <tr> 886 <td class="bar">|</td> 887 <td><code>U+2030</code> … <code>U+d7ff</code></td> 888 </tr> 889 <tr> 890 <td class="bar">|</td> 891 <td><code>U+e000</code> … <code>U+ffef</code></td> 892 </tr> 893 <tr> 894 <td class="bar">|</td> 895 <td><code>U+10000</code> … <code>U+10ffff</code></td> 896 </tr> 897 </table> 898 899 <h3><i>MemberName</i></h3> 900 <h4>used by field_id_item and method_id_item</h4> 901 902 <p>A <i>MemberName</i> is the name of a member of a class, members being 903 fields, methods, and inner classes.</p> 904 905 <table class="bnf"> 906 <tr><td colspan="2" class="def"><i>MemberName</i> →</td></tr> 907 <tr> 908 <td/> 909 <td><i>SimpleName</i></td> 910 </tr> 911 <tr> 912 <td class="bar">|</td> 913 <td><code>'<'</code> <i>SimpleName</i> <code>'>'</code></td> 914 </tr> 915 </table> 916 917 <h3><i>FullClassName</i></h3> 918 919 <p>A <i>FullClassName</i> is a fully-qualified class name, including an 920 optional package specifier followed by a required name.</p> 921 922 <table class="bnf"> 923 <tr><td colspan="2" class="def"><i>FullClassName</i> →</td></tr> 924 <tr> 925 <td/> 926 <td><i>OptionalPackagePrefix</i> <i>SimpleName</i></td> 927 </tr> 928 929 <tr><td colspan="2" class="def"><i>OptionalPackagePrefix</i> →</td></tr> 930 <tr> 931 <td/> 932 <td>(<i>SimpleName</i> <code>'/'</code>)*</td> 933 </tr> 934 </table> 935 936 <h3><i>TypeDescriptor</i></h3> 937 <h4>used by type_id_item</h4> 938 939 <p>A <i>TypeDescriptor</i> is the representation of any type, including 940 primitives, classes, arrays, and <code>void</code>. See below for 941 the meaning of the various versions.</p> 942 943 <table class="bnf"> 944 <tr><td colspan="2" class="def"><i>TypeDescriptor</i> →</td></tr> 945 <tr> 946 <td/> 947 <td><code>'V'</code></td> 948 </tr> 949 <tr> 950 <td class="bar">|</td> 951 <td><i>FieldTypeDescriptor</i></td> 952 </tr> 953 954 <tr><td colspan="2" class="def"><i>FieldTypeDescriptor</i> →</td></tr> 955 <tr> 956 <td/> 957 <td><i>NonArrayFieldTypeDescriptor</i></td> 958 </tr> 959 <tr> 960 <td class="bar">|</td> 961 <td>(<code>'['</code> * 1…255) 962 <i>NonArrayFieldTypeDescriptor</i></td> 963 </tr> 964 965 <tr> 966 <td colspan="2" class="def"><i>NonArrayFieldTypeDescriptor</i>→</td> 967 </tr> 968 <tr> 969 <td/> 970 <td><code>'Z'</code></td> 971 </tr> 972 <tr> 973 <td class="bar">|</td> 974 <td><code>'B'</code></td> 975 </tr> 976 <tr> 977 <td class="bar">|</td> 978 <td><code>'S'</code></td> 979 </tr> 980 <tr> 981 <td class="bar">|</td> 982 <td><code>'C'</code></td> 983 </tr> 984 <tr> 985 <td class="bar">|</td> 986 <td><code>'I'</code></td> 987 </tr> 988 <tr> 989 <td class="bar">|</td> 990 <td><code>'J'</code></td> 991 </tr> 992 <tr> 993 <td class="bar">|</td> 994 <td><code>'F'</code></td> 995 </tr> 996 <tr> 997 <td class="bar">|</td> 998 <td><code>'D'</code></td> 999 </tr> 1000 <tr> 1001 <td class="bar">|</td> 1002 <td><code>'L'</code> <i>FullClassName</i> <code>';'</code></td> 1003 </tr> 1004 </table> 1005 1006 <h3><i>ShortyDescriptor</i></h3> 1007 <h4>used by proto_id_item</h4> 1008 1009 <p>A <i>ShortyDescriptor</i> is the short form representation of a method 1010 prototype, including return and parameter types, except that there is 1011 no distinction between various reference (class or array) types. Instead, 1012 all reference types are represented by a single <code>'L'</code> character.</p> 1013 1014 <table class="bnf"> 1015 <tr><td colspan="2" class="def"><i>ShortyDescriptor</i> →</td></tr> 1016 <tr> 1017 <td/> 1018 <td><i>ShortyReturnType</i> (<i>ShortyFieldType</i>)*</td> 1019 </tr> 1020 1021 <tr><td colspan="2" class="def"><i>ShortyReturnType</i> →</td></tr> 1022 <tr> 1023 <td/> 1024 <td><code>'V'</code></td> 1025 </tr> 1026 <tr> 1027 <td class="bar">|</td> 1028 <td><i>ShortyFieldType</i></td> 1029 </tr> 1030 1031 <tr><td colspan="2" class="def"><i>ShortyFieldType</i> →</td></tr> 1032 <tr> 1033 <td/> 1034 <td><code>'Z'</code></td> 1035 </tr> 1036 <tr> 1037 <td class="bar">|</td> 1038 <td><code>'B'</code></td> 1039 </tr> 1040 <tr> 1041 <td class="bar">|</td> 1042 <td><code>'S'</code></td> 1043 </tr> 1044 <tr> 1045 <td class="bar">|</td> 1046 <td><code>'C'</code></td> 1047 </tr> 1048 <tr> 1049 <td class="bar">|</td> 1050 <td><code>'I'</code></td> 1051 </tr> 1052 <tr> 1053 <td class="bar">|</td> 1054 <td><code>'J'</code></td> 1055 </tr> 1056 <tr> 1057 <td class="bar">|</td> 1058 <td><code>'F'</code></td> 1059 </tr> 1060 <tr> 1061 <td class="bar">|</td> 1062 <td><code>'D'</code></td> 1063 </tr> 1064 <tr> 1065 <td class="bar">|</td> 1066 <td><code>'L'</code></td> 1067 </tr> 1068 </table> 1069 1070 <h3><i>TypeDescriptor</i> Semantics</h3> 1071 1072 <p>This is the meaning of each of the variants of <i>TypeDescriptor</i>.</p> 1073 1074 <table class="descriptor"> 1075 <thead> 1076 <tr> 1077 <th>Syntax</th> 1078 <th>Meaning</th> 1079 </tr> 1080 </thead> 1081 <tbody> 1082 <tr> 1083 <td>V</td> 1084 <td><code>void</code>; only valid for return types</td> 1085 </tr> 1086 <tr> 1087 <td>Z</td> 1088 <td><code>boolean</code></td> 1089 </tr> 1090 <tr> 1091 <td>B</td> 1092 <td><code>byte</code></td> 1093 </tr> 1094 <tr> 1095 <td>S</td> 1096 <td><code>short</code></td> 1097 </tr> 1098 <tr> 1099 <td>C</td> 1100 <td><code>char</code></td> 1101 </tr> 1102 <tr> 1103 <td>I</td> 1104 <td><code>int</code></td> 1105 </tr> 1106 <tr> 1107 <td>J</td> 1108 <td><code>long</code></td> 1109 </tr> 1110 <tr> 1111 <td>F</td> 1112 <td><code>float</code></td> 1113 </tr> 1114 <tr> 1115 <td>D</td> 1116 <td><code>double</code></td> 1117 </tr> 1118 <tr> 1119 <td>L<i>fully/qualified/Name</i>;</td> 1120 <td>the class <code><i>fully.qualified.Name</i></code></td> 1121 </tr> 1122 <tr> 1123 <td>[<i>descriptor</i></td> 1124 <td>array of <code><i>descriptor</i></code>, usable recursively for 1125 arrays-of-arrays, though it is invalid to have more than 255 1126 dimensions. 1127 </td> 1128 </tr> 1129 </tbody> 1130 </table> 1131 1132 <h2>Items and Related Structures</h2> 1133 1134 <p>This section includes definitions for each of the top-level items that 1135 may appear in a <code>.dex</code> file. 1136 1137 <h3>header_item</h3> 1138 <h4>appears in the header section</h4> 1139 <h4>alignment: 4 bytes</h4> 1140 1141 <table class="format"> 1142 <thead> 1143 <tr> 1144 <th>Name</th> 1145 <th>Format</th> 1146 <th>Description</th> 1147 </tr> 1148 </thead> 1149 <tbody> 1150 <tr> 1151 <td>magic</td> 1152 <td>ubyte[8] = DEX_FILE_MAGIC</td> 1153 <td>magic value. See discussion above under "<code>DEX_FILE_MAGIC</code>" 1154 for more details. 1155 </td> 1156 </tr> 1157 <tr> 1158 <td>checksum</td> 1159 <td>uint</td> 1160 <td>adler32 checksum of the rest of the file (everything but 1161 <code>magic</code> and this field); used to detect file corruption 1162 </td> 1163 </tr> 1164 <tr> 1165 <td>signature</td> 1166 <td>ubyte[20]</td> 1167 <td>SHA-1 signature (hash) of the rest of the file (everything but 1168 <code>magic</code>, <code>checksum</code>, and this field); used 1169 to uniquely identify files 1170 </td> 1171 </tr> 1172 <tr> 1173 <td>file_size</td> 1174 <td>uint</td> 1175 <td>size of the entire file (including the header), in bytes 1176 </tr> 1177 <tr> 1178 <td>header_size</td> 1179 <td>uint = 0x70</td> 1180 <td>size of the header (this entire section), in bytes. This allows for at 1181 least a limited amount of backwards/forwards compatibility without 1182 invalidating the format. 1183 </td> 1184 </tr> 1185 <tr> 1186 <td>endian_tag</td> 1187 <td>uint = ENDIAN_CONSTANT</td> 1188 <td>endianness tag. See discussion above under "<code>ENDIAN_CONSTANT</code> 1189 and <code>REVERSE_ENDIAN_CONSTANT</code>" for more details. 1190 </td> 1191 </tr> 1192 <tr> 1193 <td>link_size</td> 1194 <td>uint</td> 1195 <td>size of the link section, or <code>0</code> if this file isn't 1196 statically linked</td> 1197 </tr> 1198 <tr> 1199 <td>link_off</td> 1200 <td>uint</td> 1201 <td>offset from the start of the file to the link section, or 1202 <code>0</code> if <code>link_size == 0</code>. The offset, if non-zero, 1203 should be to an offset into the <code>link_data</code> section. The 1204 format of the data pointed at is left unspecified by this document; 1205 this header field (and the previous) are left as hooks for use by 1206 runtime implementations. 1207 </td> 1208 </tr> 1209 <tr> 1210 <td>map_off</td> 1211 <td>uint</td> 1212 <td>offset from the start of the file to the map item, or 1213 <code>0</code> if this file has no map. The offset, if non-zero, 1214 should be to an offset into the <code>data</code> section, 1215 and the data should be in the format specified by "<code>map_list</code>" 1216 below. 1217 </td> 1218 </tr> 1219 <tr> 1220 <td>string_ids_size</td> 1221 <td>uint</td> 1222 <td>count of strings in the string identifiers list</td> 1223 </tr> 1224 <tr> 1225 <td>string_ids_off</td> 1226 <td>uint</td> 1227 <td>offset from the start of the file to the string identifiers list, or 1228 <code>0</code> if <code>string_ids_size == 0</code> (admittedly a 1229 strange edge case). The offset, if non-zero, 1230 should be to the start of the <code>string_ids</code> section. 1231 </td> 1232 </tr> 1233 <tr> 1234 <td>type_ids_size</td> 1235 <td>uint</td> 1236 <td>count of elements in the type identifiers list</td> 1237 </tr> 1238 <tr> 1239 <td>type_ids_off</td> 1240 <td>uint</td> 1241 <td>offset from the start of the file to the type identifiers list, or 1242 <code>0</code> if <code>type_ids_size == 0</code> (admittedly a 1243 strange edge case). The offset, if non-zero, 1244 should be to the start of the <code>type_ids</code> 1245 section. 1246 </td> 1247 </tr> 1248 <tr> 1249 <td>proto_ids_size</td> 1250 <td>uint</td> 1251 <td>count of elements in the prototype identifiers list</td> 1252 </tr> 1253 <tr> 1254 <td>proto_ids_off</td> 1255 <td>uint</td> 1256 <td>offset from the start of the file to the prototype identifiers list, or 1257 <code>0</code> if <code>proto_ids_size == 0</code> (admittedly a 1258 strange edge case). The offset, if non-zero, 1259 should be to the start of the <code>proto_ids</code> 1260 section. 1261 </td> 1262 </tr> 1263 <tr> 1264 <td>field_ids_size</td> 1265 <td>uint</td> 1266 <td>count of elements in the field identifiers list</td> 1267 </tr> 1268 <tr> 1269 <td>field_ids_off</td> 1270 <td>uint</td> 1271 <td>offset from the start of the file to the field identifiers list, or 1272 <code>0</code> if <code>field_ids_size == 0</code>. The offset, if 1273 non-zero, should be to the start of the <code>field_ids</code> 1274 section.</td> 1275 </td> 1276 </tr> 1277 <tr> 1278 <td>method_ids_size</td> 1279 <td>uint</td> 1280 <td>count of elements in the method identifiers list</td> 1281 </tr> 1282 <tr> 1283 <td>method_ids_off</td> 1284 <td>uint</td> 1285 <td>offset from the start of the file to the method identifiers list, or 1286 <code>0</code> if <code>method_ids_size == 0</code>. The offset, if 1287 non-zero, should be to the start of the <code>method_ids</code> 1288 section.</td> 1289 </tr> 1290 <tr> 1291 <td>class_defs_size</td> 1292 <td>uint</td> 1293 <td>count of elements in the class definitions list</td> 1294 </tr> 1295 <tr> 1296 <td>class_defs_off</td> 1297 <td>uint</td> 1298 <td>offset from the start of the file to the class definitions list, or 1299 <code>0</code> if <code>class_defs_size == 0</code> (admittedly a 1300 strange edge case). The offset, if non-zero, 1301 should be to the start of the <code>class_defs</code> section. 1302 </td> 1303 </tr> 1304 <tr> 1305 <td>data_size</td> 1306 <td>uint</td> 1307 <td>Size of <code>data</code> section in bytes. Must be an even 1308 multiple of sizeof(uint).</td> 1309 </tr> 1310 <tr> 1311 <td>data_off</td> 1312 <td>uint</td> 1313 <td>offset from the start of the file to the start of the 1314 <code>data</code> section. 1315 </td> 1316 </tr> 1317 </tbody> 1318 </table> 1319 1320 <h3>map_list</h3> 1321 <h4>appears in the data section</h4> 1322 <h4>referenced from header_item</h4> 1323 <h4>alignment: 4 bytes</h4> 1324 1325 <p>This is a list of the entire contents of a file, in order. It 1326 contains some redundancy with respect to the <code>header_item</code> 1327 but is intended to be an easy form to use to iterate over an entire 1328 file. A given type must appear at most once in a map, but there is no 1329 restriction on what order types may appear in, other than the 1330 restrictions implied by the rest of the format (e.g., a 1331 <code>header</code> section must appear first, followed by a 1332 <code>string_ids</code> section, etc.). Additionally, the map entries must 1333 be ordered by initial offset and must not overlap.</p> 1334 1335 <table class="format"> 1336 <thead> 1337 <tr> 1338 <th>Name</th> 1339 <th>Format</th> 1340 <th>Description</th> 1341 </tr> 1342 </thead> 1343 <tbody> 1344 <tr> 1345 <td>size</td> 1346 <td>uint</td> 1347 <td>size of the list, in entries</td> 1348 </tr> 1349 <tr> 1350 <td>list</td> 1351 <td>map_item[size]</td> 1352 <td>elements of the list</td> 1353 </tr> 1354 </tbody> 1355 </table> 1356 1357 <h3>map_item Format</h3> 1358 1359 <table class="format"> 1360 <thead> 1361 <tr> 1362 <th>Name</th> 1363 <th>Format</th> 1364 <th>Description</th> 1365 </tr> 1366 </thead> 1367 <tbody> 1368 <tr> 1369 <td>type</td> 1370 <td>ushort</td> 1371 <td>type of the items; see table below</td> 1372 </tr> 1373 <tr> 1374 <td>unused</td> 1375 <td>ushort</td> 1376 <td><i>(unused)</i></td> 1377 </tr> 1378 <tr> 1379 <td>size</td> 1380 <td>uint</td> 1381 <td>count of the number of items to be found at the indicated offset</td> 1382 </tr> 1383 <tr> 1384 <td>offset</td> 1385 <td>uint</td> 1386 <td>offset from the start of the file to the items in question</td> 1387 </tr> 1388 </tbody> 1389 </table> 1390 1391 1392 <h3>Type Codes</h3> 1393 1394 <table class="typeCodes"> 1395 <thead> 1396 <tr> 1397 <th>Item Type</th> 1398 <th>Constant</th> 1399 <th>Value</th> 1400 <th>Item Size In Bytes</th> 1401 </tr> 1402 </thead> 1403 <tbody> 1404 <tr> 1405 <td>header_item</td> 1406 <td>TYPE_HEADER_ITEM</td> 1407 <td>0x0000</td> 1408 <td>0x70</td> 1409 </tr> 1410 <tr> 1411 <td>string_id_item</td> 1412 <td>TYPE_STRING_ID_ITEM</td> 1413 <td>0x0001</td> 1414 <td>0x04</td> 1415 </tr> 1416 <tr> 1417 <td>type_id_item</td> 1418 <td>TYPE_TYPE_ID_ITEM</td> 1419 <td>0x0002</td> 1420 <td>0x04</td> 1421 </tr> 1422 <tr> 1423 <td>proto_id_item</td> 1424 <td>TYPE_PROTO_ID_ITEM</td> 1425 <td>0x0003</td> 1426 <td>0x0c</td> 1427 </tr> 1428 <tr> 1429 <td>field_id_item</td> 1430 <td>TYPE_FIELD_ID_ITEM</td> 1431 <td>0x0004</td> 1432 <td>0x08</td> 1433 </tr> 1434 <tr> 1435 <td>method_id_item</td> 1436 <td>TYPE_METHOD_ID_ITEM</td> 1437 <td>0x0005</td> 1438 <td>0x08</td> 1439 </tr> 1440 <tr> 1441 <td>class_def_item</td> 1442 <td>TYPE_CLASS_DEF_ITEM</td> 1443 <td>0x0006</td> 1444 <td>0x20</td> 1445 </tr> 1446 <tr> 1447 <td>map_list</td> 1448 <td>TYPE_MAP_LIST</td> 1449 <td>0x1000</td> 1450 <td>4 + (item.size * 12)</td> 1451 </tr> 1452 <tr> 1453 <td>type_list</td> 1454 <td>TYPE_TYPE_LIST</td> 1455 <td>0x1001</td> 1456 <td>4 + (item.size * 2)</td> 1457 </tr> 1458 <tr> 1459 <td>annotation_set_ref_list</td> 1460 <td>TYPE_ANNOTATION_SET_REF_LIST</td> 1461 <td>0x1002</td> 1462 <td>4 + (item.size * 4)</td> 1463 </tr> 1464 <tr> 1465 <td>annotation_set_item</td> 1466 <td>TYPE_ANNOTATION_SET_ITEM</td> 1467 <td>0x1003</td> 1468 <td>4 + (item.size * 4)</td> 1469 </tr> 1470 <tr> 1471 <td>class_data_item</td> 1472 <td>TYPE_CLASS_DATA_ITEM</td> 1473 <td>0x2000</td> 1474 <td><i>implicit; must parse</i></td> 1475 </tr> 1476 <tr> 1477 <td>code_item</td> 1478 <td>TYPE_CODE_ITEM</td> 1479 <td>0x2001</td> 1480 <td><i>implicit; must parse</i></td> 1481 </tr> 1482 <tr> 1483 <td>string_data_item</td> 1484 <td>TYPE_STRING_DATA_ITEM</td> 1485 <td>0x2002</td> 1486 <td><i>implicit; must parse</i></td> 1487 </tr> 1488 <tr> 1489 <td>debug_info_item</td> 1490 <td>TYPE_DEBUG_INFO_ITEM</td> 1491 <td>0x2003</td> 1492 <td><i>implicit; must parse</i></td> 1493 </tr> 1494 <tr> 1495 <td>annotation_item</td> 1496 <td>TYPE_ANNOTATION_ITEM</td> 1497 <td>0x2004</td> 1498 <td><i>implicit; must parse</i></td> 1499 </tr> 1500 <tr> 1501 <td>encoded_array_item</td> 1502 <td>TYPE_ENCODED_ARRAY_ITEM</td> 1503 <td>0x2005</td> 1504 <td><i>implicit; must parse</i></td> 1505 </tr> 1506 <tr> 1507 <td>annotations_directory_item</td> 1508 <td>TYPE_ANNOTATIONS_DIRECTORY_ITEM</td> 1509 <td>0x2006</td> 1510 <td><i>implicit; must parse</i></td> 1511 </tr> 1512 </tbody> 1513 </table> 1514 1515 1516 <h3>string_id_item</h3> 1517 <h4>appears in the string_ids section</h4> 1518 <h4>alignment: 4 bytes</h4> 1519 1520 <table class="format"> 1521 <thead> 1522 <tr> 1523 <th>Name</th> 1524 <th>Format</th> 1525 <th>Description</th> 1526 </tr> 1527 </thead> 1528 <tbody> 1529 <tr> 1530 <td>string_data_off</td> 1531 <td>uint</td> 1532 <td>offset from the start of the file to the string data for this 1533 item. The offset should be to a location 1534 in the <code>data</code> section, and the data should be in the 1535 format specified by "<code>string_data_item</code>" below. 1536 There is no alignment requirement for the offset. 1537 </td> 1538 </tr> 1539 </tbody> 1540 </table> 1541 1542 <h3>string_data_item</h3> 1543 <h4>appears in the data section</h4> 1544 <h4>alignment: none (byte-aligned)</h4> 1545 1546 <table class="format"> 1547 <thead> 1548 <tr> 1549 <th>Name</th> 1550 <th>Format</th> 1551 <th>Description</th> 1552 </tr> 1553 </thead> 1554 <tbody> 1555 <tr> 1556 <td>utf16_size</td> 1557 <td>uleb128</td> 1558 <td>size of this string, in UTF-16 code units (which is the "string 1559 length" in many systems). That is, this is the decoded length of 1560 the string. (The encoded length is implied by the position of 1561 the <code>0</code> byte.)</td> 1562 </tr> 1563 <tr> 1564 <td>data</td> 1565 <td>ubyte[]</td> 1566 <td>a series of MUTF-8 code units (a.k.a. octets, a.k.a. bytes) 1567 followed by a byte of value <code>0</code>. See 1568 "MUTF-8 (Modified UTF-8) Encoding" above for details and 1569 discussion about the data format. 1570 <p><b>Note:</b> It is acceptable to have a string which includes 1571 (the encoded form of) UTF-16 surrogate code units (that is, 1572 <code>U+d800</code> … <code>U+dfff</code>) 1573 either in isolation or out-of-order with respect to the usual 1574 encoding of Unicode into UTF-16. It is up to higher-level uses of 1575 strings to reject such invalid encodings, if appropriate.</p> 1576 </td> 1577 </tr> 1578 </tbody> 1579 </table> 1580 1581 <h3>type_id_item</h3> 1582 <h4>appears in the type_ids section</h4> 1583 <h4>alignment: 4 bytes</h4> 1584 1585 <table class="format"> 1586 <thead> 1587 <tr> 1588 <th>Name</th> 1589 <th>Format</th> 1590 <th>Description</th> 1591 </tr> 1592 </thead> 1593 <tbody> 1594 <tr> 1595 <td>descriptor_idx</td> 1596 <td>uint</td> 1597 <td>index into the <code>string_ids</code> list for the descriptor 1598 string of this type. The string must conform to the syntax for 1599 <i>TypeDescriptor</i>, defined above. 1600 </td> 1601 </tr> 1602 </tbody> 1603 </table> 1604 1605 <h3>proto_id_item</h3> 1606 <h4>appears in the proto_ids section</h4> 1607 <h4>alignment: 4 bytes</h4> 1608 1609 <table class="format"> 1610 <thead> 1611 <tr> 1612 <th>Name</th> 1613 <th>Format</th> 1614 <th>Description</th> 1615 </tr> 1616 </thead> 1617 <tbody> 1618 <tr> 1619 <td>shorty_idx</td> 1620 <td>uint</td> 1621 <td>index into the <code>string_ids</code> list for the short-form 1622 descriptor string of this prototype. The string must conform to the 1623 syntax for <i>ShortyDescriptor</i>, defined above, and must correspond 1624 to the return type and parameters of this item. 1625 </td> 1626 </tr> 1627 <tr> 1628 <td>return_type_idx</td> 1629 <td>uint</td> 1630 <td>index into the <code>type_ids</code> list for the return type 1631 of this prototype 1632 </td> 1633 </tr> 1634 <tr> 1635 <td>parameters_off</td> 1636 <td>uint</td> 1637 <td>offset from the start of the file to the list of parameter types 1638 for this prototype, or <code>0</code> if this prototype has no 1639 parameters. This offset, if non-zero, should be in the 1640 <code>data</code> section, and the data there should be in the 1641 format specified by <code>"type_list"</code> below. Additionally, there 1642 should be no reference to the type <code>void</code> in the list. 1643 </td> 1644 </tr> 1645 </tbody> 1646 </table> 1647 1648 <h3>field_id_item</h3> 1649 <h4>appears in the field_ids section</h4> 1650 <h4>alignment: 4 bytes</h4> 1651 1652 <table class="format"> 1653 <thead> 1654 <tr> 1655 <th>Name</th> 1656 <th>Format</th> 1657 <th>Description</th> 1658 </tr> 1659 </thead> 1660 <tbody> 1661 <tr> 1662 <td>class_idx</td> 1663 <td>ushort</td> 1664 <td>index into the <code>type_ids</code> list for the definer of this 1665 field. This must be a class type, and not an array or primitive type. 1666 </td> 1667 </tr> 1668 <tr> 1669 <td>type_idx</td> 1670 <td>ushort</td> 1671 <td>index into the <code>type_ids</code> list for the type of 1672 this field 1673 </td> 1674 </tr> 1675 <tr> 1676 <td>name_idx</td> 1677 <td>uint</td> 1678 <td>index into the <code>string_ids</code> list for the name of this 1679 field. The string must conform to the syntax for <i>MemberName</i>, 1680 defined above. 1681 </td> 1682 </tr> 1683 </tbody> 1684 </table> 1685 1686 <h3>method_id_item</h3> 1687 <h4>appears in the method_ids section</h4> 1688 <h4>alignment: 4 bytes</h4> 1689 1690 <table class="format"> 1691 <thead> 1692 <tr> 1693 <th>Name</th> 1694 <th>Format</th> 1695 <th>Description</th> 1696 </tr> 1697 </thead> 1698 <tbody> 1699 <tr> 1700 <td>class_idx</td> 1701 <td>ushort</td> 1702 <td>index into the <code>type_ids</code> list for the definer of this 1703 method. This must be a class or array type, and not a primitive type. 1704 </td> 1705 </tr> 1706 <tr> 1707 <td>proto_idx</td> 1708 <td>ushort</td> 1709 <td>index into the <code>proto_ids</code> list for the prototype of 1710 this method 1711 </td> 1712 </tr> 1713 <tr> 1714 <td>name_idx</td> 1715 <td>uint</td> 1716 <td>index into the <code>string_ids</code> list for the name of this 1717 method. The string must conform to the syntax for <i>MemberName</i>, 1718 defined above. 1719 </td> 1720 </tr> 1721 </tbody> 1722 </table> 1723 1724 <h3>class_def_item</h3> 1725 <h4>appears in the class_defs section</h4> 1726 <h4>alignment: 4 bytes</h4> 1727 1728 <table class="format"> 1729 <thead> 1730 <tr> 1731 <th>Name</th> 1732 <th>Format</th> 1733 <th>Description</th> 1734 </tr> 1735 </thead> 1736 <tbody> 1737 <tr> 1738 <td>class_idx</td> 1739 <td>uint</td> 1740 <td>index into the <code>type_ids</code> list for this class. 1741 This must be a class type, and not an array or primitive type. 1742 </td> 1743 </tr> 1744 <tr> 1745 <td>access_flags</td> 1746 <td>uint</td> 1747 <td>access flags for the class (<code>public</code>, <code>final</code>, 1748 etc.). See "<code>access_flags</code> Definitions" for details. 1749 </td> 1750 </tr> 1751 <tr> 1752 <td>superclass_idx</td> 1753 <td>uint</td> 1754 <td>index into the <code>type_ids</code> list for the superclass, or 1755 the constant value <code>NO_INDEX</code> if this class has no 1756 superclass (i.e., it is a root class such as <code>Object</code>). 1757 If present, this must be a class type, and not an array or primitive type. 1758 </td> 1759 </tr> 1760 <tr> 1761 <td>interfaces_off</td> 1762 <td>uint</td> 1763 <td>offset from the start of the file to the list of interfaces, or 1764 <code>0</code> if there are none. This offset 1765 should be in the <code>data</code> section, and the data 1766 there should be in the format specified by 1767 "<code>type_list</code>" below. Each of the elements of the list 1768 must be a class type (not an array or primitive type), and there 1769 must not be any duplicates. 1770 </td> 1771 </tr> 1772 <tr> 1773 <td>source_file_idx</td> 1774 <td>uint</td> 1775 <td>index into the <code>string_ids</code> list for the name of the 1776 file containing the original source for (at least most of) this class, 1777 or the special value <code>NO_INDEX</code> to represent a lack of 1778 this information. The <code>debug_info_item</code> of any given method 1779 may override this source file, but the expectation is that most classes 1780 will only come from one source file. 1781 </td> 1782 </tr> 1783 <tr> 1784 <td>annotations_off</td> 1785 <td>uint</td> 1786 <td>offset from the start of the file to the annotations structure 1787 for this class, or <code>0</code> if there are no annotations on 1788 this class. This offset, if non-zero, should be in the 1789 <code>data</code> section, and the data there should be in 1790 the format specified by "<code>annotations_directory_item</code>" below, 1791 with all items referring to this class as the definer. 1792 </td> 1793 </tr> 1794 <tr> 1795 <td>class_data_off</td> 1796 <td>uint</td> 1797 <td>offset from the start of the file to the associated 1798 class data for this item, or <code>0</code> if there is no class 1799 data for this class. (This may be the case, for example, if this class 1800 is a marker interface.) The offset, if non-zero, should be in the 1801 <code>data</code> section, and the data there should be in the 1802 format specified by "<code>class_data_item</code>" below, with all 1803 items referring to this class as the definer. 1804 </td> 1805 </tr> 1806 <tr> 1807 <td>static_values_off</td> 1808 <td>uint</td> 1809 <td>offset from the start of the file to the list of initial 1810 values for <code>static</code> fields, or <code>0</code> if there 1811 are none (and all <code>static</code> fields are to be initialized with 1812 <code>0</code> or <code>null</code>). This offset should be in the 1813 <code>data</code> section, and the data there should be in the 1814 format specified by "<code>encoded_array_item</code>" below. The size 1815 of the array must be no larger than the number of <code>static</code> 1816 fields declared by this class, and the elements correspond to the 1817 <code>static</code> fields in the same order as declared in the 1818 corresponding <code>field_list</code>. The type of each array 1819 element must match the declared type of its corresponding field. 1820 If there are fewer elements in the array than there are 1821 <code>static</code> fields, then the leftover fields are initialized 1822 with a type-appropriate <code>0</code> or <code>null</code>. 1823 </td> 1824 </tr> 1825 </tbody> 1826 </table> 1827 1828 <h3>class_data_item</h3> 1829 <h4>referenced from class_def_item</h4> 1830 <h4>appears in the data section</h4> 1831 <h4>alignment: none (byte-aligned)</h4> 1832 1833 <table class="format"> 1834 <thead> 1835 <tr> 1836 <th>Name</th> 1837 <th>Format</th> 1838 <th>Description</th> 1839 </tr> 1840 </thead> 1841 <tbody> 1842 <tr> 1843 <td>static_fields_size</td> 1844 <td>uleb128</td> 1845 <td>the number of static fields defined in this item</td> 1846 </tr> 1847 <tr> 1848 <td>instance_fields_size</td> 1849 <td>uleb128</td> 1850 <td>the number of instance fields defined in this item</td> 1851 </tr> 1852 <tr> 1853 <td>direct_methods_size</td> 1854 <td>uleb128</td> 1855 <td>the number of direct methods defined in this item</td> 1856 </tr> 1857 <tr> 1858 <td>virtual_methods_size</td> 1859 <td>uleb128</td> 1860 <td>the number of virtual methods defined in this item</td> 1861 </tr> 1862 <tr> 1863 <td>static_fields</td> 1864 <td>encoded_field[static_fields_size]</td> 1865 <td>the defined static fields, represented as a sequence of 1866 encoded elements. The fields must be sorted by 1867 <code>field_idx</code> in increasing order. 1868 </td> 1869 </tr> 1870 <tr> 1871 <td>instance_fields</td> 1872 <td>encoded_field[instance_fields_size]</td> 1873 <td>the defined instance fields, represented as a sequence of 1874 encoded elements. The fields must be sorted by 1875 <code>field_idx</code> in increasing order. 1876 </td> 1877 </tr> 1878 <tr> 1879 <td>direct_methods</td> 1880 <td>encoded_method[direct_methods_size]</td> 1881 <td>the defined direct (any of <code>static</code>, <code>private</code>, 1882 or constructor) methods, represented as a sequence of 1883 encoded elements. The methods must be sorted by 1884 <code>method_idx</code> in increasing order. 1885 </td> 1886 </tr> 1887 <tr> 1888 <td>virtual_methods</td> 1889 <td>encoded_method[virtual_methods_size]</td> 1890 <td>the defined virtual (none of <code>static</code>, <code>private</code>, 1891 or constructor) methods, represented as a sequence of 1892 encoded elements. This list should <i>not</i> include inherited 1893 methods unless overridden by the class that this item represents. The 1894 methods must be sorted by <code>method_idx</code> in increasing order. 1895 </td> 1896 </tr> 1897 </tbody> 1898 </table> 1899 1900 <p><b>Note:</b> All elements' <code>field_id</code>s and 1901 <code>method_id</code>s must refer to the same defining class.</p> 1902 1903 <h3>encoded_field Format</h3> 1904 1905 <table class="format"> 1906 <thead> 1907 <tr> 1908 <th>Name</th> 1909 <th>Format</th> 1910 <th>Description</th> 1911 </tr> 1912 </thead> 1913 <tbody> 1914 <tr> 1915 <td>field_idx_diff</td> 1916 <td>uleb128</td> 1917 <td>index into the <code>field_ids</code> list for the identity of this 1918 field (includes the name and descriptor), represented as a difference 1919 from the index of previous element in the list. The index of the 1920 first element in a list is represented directly. 1921 </td> 1922 </tr> 1923 <tr> 1924 <td>access_flags</td> 1925 <td>uleb128</td> 1926 <td>access flags for the field (<code>public</code>, <code>final</code>, 1927 etc.). See "<code>access_flags</code> Definitions" for details. 1928 </td> 1929 </tr> 1930 </tbody> 1931 </table> 1932 1933 <h3>encoded_method Format</h3> 1934 1935 <table class="format"> 1936 <thead> 1937 <tr> 1938 <th>Name</th> 1939 <th>Format</th> 1940 <th>Description</th> 1941 </tr> 1942 </thead> 1943 <tbody> 1944 <tr> 1945 <td>method_idx_diff</td> 1946 <td>uleb128</td> 1947 <td>index into the <code>method_ids</code> list for the identity of this 1948 method (includes the name and descriptor), represented as a difference 1949 from the index of previous element in the list. The index of the 1950 first element in a list is represented directly. 1951 </td> 1952 </tr> 1953 <tr> 1954 <td>access_flags</td> 1955 <td>uleb128</td> 1956 <td>access flags for the method (<code>public</code>, <code>final</code>, 1957 etc.). See "<code>access_flags</code> Definitions" for details. 1958 </td> 1959 </tr> 1960 <tr> 1961 <td>code_off</td> 1962 <td>uleb128</td> 1963 <td>offset from the start of the file to the code structure for this 1964 method, or <code>0</code> if this method is either <code>abstract</code> 1965 or <code>native</code>. The offset should be to a location in the 1966 <code>data</code> section. The format of the data is specified by 1967 "<code>code_item</code>" below. 1968 </td> 1969 </tr> 1970 </tbody> 1971 </table> 1972 1973 <h3>type_list</h3> 1974 <h4>referenced from class_def_item and proto_id_item</h4> 1975 <h4>appears in the data section</h4> 1976 <h4>alignment: 4 bytes</h4> 1977 1978 <table class="format"> 1979 <thead> 1980 <tr> 1981 <th>Name</th> 1982 <th>Format</th> 1983 <th>Description</th> 1984 </tr> 1985 </thead> 1986 <tbody> 1987 <tr> 1988 <td>size</td> 1989 <td>uint</td> 1990 <td>size of the list, in entries</td> 1991 </tr> 1992 <tr> 1993 <td>list</td> 1994 <td>type_item[size]</td> 1995 <td>elements of the list</td> 1996 </tr> 1997 </tbody> 1998 </table> 1999 2000 <h3>type_item Format</h3> 2001 2002 <table class="format"> 2003 <thead> 2004 <tr> 2005 <th>Name</th> 2006 <th>Format</th> 2007 <th>Description</th> 2008 </tr> 2009 </thead> 2010 <tbody> 2011 <tr> 2012 <td>type_idx</td> 2013 <td>ushort</td> 2014 <td>index into the <code>type_ids</code> list</td> 2015 </tr> 2016 </tbody> 2017 </table> 2018 2019 <h3>code_item</h3> 2020 <h4>referenced from encoded_method</h4> 2021 <h4>appears in the data section</h4> 2022 <h4>alignment: 4 bytes</h4> 2023 2024 <table class="format"> 2025 <thead> 2026 <tr> 2027 <th>Name</th> 2028 <th>Format</th> 2029 <th>Description</th> 2030 </tr> 2031 </thead> 2032 <tbody> 2033 <tr> 2034 <td>registers_size</td> 2035 <td>ushort</td> 2036 <td>the number of registers used by this code</td> 2037 </tr> 2038 <tr> 2039 <td>ins_size</td> 2040 <td>ushort</td> 2041 <td>the number of words of incoming arguments to the method that this 2042 code is for</td> 2043 </tr> 2044 <tr> 2045 <td>outs_size</td> 2046 <td>ushort</td> 2047 <td>the number of words of outgoing argument space required by this 2048 code for method invocation 2049 </td> 2050 </tr> 2051 <tr> 2052 <td>tries_size</td> 2053 <td>ushort</td> 2054 <td>the number of <code>try_item</code>s for this instance. If non-zero, 2055 then these appear as the <code>tries</code> array just after the 2056 <code>insns</code> in this instance. 2057 </td> 2058 </tr> 2059 <tr> 2060 <td>debug_info_off</td> 2061 <td>uint</td> 2062 <td>offset from the start of the file to the debug info (line numbers + 2063 local variable info) sequence for this code, or <code>0</code> if 2064 there simply is no information. The offset, if non-zero, should be 2065 to a location in the <code>data</code> section. The format of 2066 the data is specified by "<code>debug_info_item</code>" below. 2067 </td> 2068 </tr> 2069 <tr> 2070 <td>insns_size</td> 2071 <td>uint</td> 2072 <td>size of the instructions list, in 16-bit code units</td> 2073 </tr> 2074 <tr> 2075 <td>insns</td> 2076 <td>ushort[insns_size]</td> 2077 <td>actual array of bytecode. The format of code in an <code>insns</code> 2078 array is specified by the companion document 2079 <a href="dalvik-bytecode.html">"Bytecode for the Dalvik VM"</a>. Note 2080 that though this is defined as an array of <code>ushort</code>, there 2081 are some internal structures that prefer four-byte alignment. Also, 2082 if this happens to be in an endian-swapped file, then the swapping is 2083 <i>only</i> done on individual <code>ushort</code>s and not on the 2084 larger internal structures. 2085 </td> 2086 </tr> 2087 <tr> 2088 <td>padding</td> 2089 <td>ushort <i>(optional)</i> = 0</td> 2090 <td>two bytes of padding to make <code>tries</code> four-byte aligned. 2091 This element is only present if <code>tries_size</code> is non-zero 2092 and <code>insns_size</code> is odd. 2093 </td> 2094 </tr> 2095 <tr> 2096 <td>tries</td> 2097 <td>try_item[tries_size] <i>(optional)</i></td> 2098 <td>array indicating where in the code exceptions are caught and 2099 how to handle them. Elements of the array must be non-overlapping in 2100 range and in order from low to high address. This element is only 2101 present if <code>tries_size</code> is non-zero. 2102 </td> 2103 </tr> 2104 <tr> 2105 <td>handlers</td> 2106 <td>encoded_catch_handler_list <i>(optional)</i></td> 2107 <td>bytes representing a list of lists of catch types and associated 2108 handler addresses. Each <code>try_item</code> has a byte-wise offset 2109 into this structure. This element is only present if 2110 <code>tries_size</code> is non-zero. 2111 </td> 2112 </tr> 2113 </tbody> 2114 </table> 2115 2116 <h3>try_item Format</h3> 2117 2118 <table class="format"> 2119 <thead> 2120 <tr> 2121 <th>Name</th> 2122 <th>Format</th> 2123 <th>Description</th> 2124 </tr> 2125 </thead> 2126 <tbody> 2127 <tr> 2128 <td>start_addr</td> 2129 <td>uint</td> 2130 <td>start address of the block of code covered by this entry. The address 2131 is a count of 16-bit code units to the start of the first covered 2132 instruction. 2133 </td> 2134 </tr> 2135 <tr> 2136 <td>insn_count</td> 2137 <td>ushort</td> 2138 <td>number of 16-bit code units covered by this entry. The last code 2139 unit covered (inclusive) is <code>start_addr + insn_count - 1</code>. 2140 </td> 2141 </tr> 2142 <tr> 2143 <td>handler_off</td> 2144 <td>ushort</td> 2145 <td>offset in bytes from the start of the associated 2146 <code>encoded_catch_hander_list</code> to the 2147 <code>encoded_catch_handler</code> for this entry. This must be an 2148 offset to the start of an <code>encoded_catch_handler</code>. 2149 </td> 2150 </tr> 2151 </tbody> 2152 </table> 2153 2154 <h3>encoded_catch_handler_list Format</h3> 2155 2156 <table class="format"> 2157 <thead> 2158 <tr> 2159 <th>Name</th> 2160 <th>Format</th> 2161 <th>Description</th> 2162 </tr> 2163 </thead> 2164 <tbody> 2165 <tr> 2166 <td>size</td> 2167 <td>uleb128</td> 2168 <td>size of this list, in entries</td> 2169 </tr> 2170 <tr> 2171 <td>list</td> 2172 <td>encoded_catch_handler[handlers_size]</td> 2173 <td>actual list of handler lists, represented directly (not as offsets), 2174 and concatenated sequentially</td> 2175 </tr> 2176 </tbody> 2177 </table> 2178 2179 <h3>encoded_catch_handler Format</h3> 2180 2181 <table class="format"> 2182 <thead> 2183 <tr> 2184 <th>Name</th> 2185 <th>Format</th> 2186 <th>Description</th> 2187 </tr> 2188 </thead> 2189 <tbody> 2190 <tr> 2191 <td>size</td> 2192 <td>sleb128</td> 2193 <td>number of catch types in this list. If non-positive, then this is 2194 the negative of the number of catch types, and the catches are followed 2195 by a catch-all handler. For example: A <code>size</code> of <code>0</code> 2196 means that there is a catch-all but no explicitly typed catches. 2197 A <code>size</code> of <code>2</code> means that there are two explicitly 2198 typed catches and no catch-all. And a <code>size</code> of <code>-1</code> 2199 means that there is one typed catch along with a catch-all. 2200 </td> 2201 </tr> 2202 <tr> 2203 <td>handlers</td> 2204 <td>encoded_type_addr_pair[abs(size)]</td> 2205 <td>stream of <code>abs(size)</code> encoded items, one for each caught 2206 type, in the order that the types should be tested. 2207 </td> 2208 </tr> 2209 <tr> 2210 <td>catch_all_addr</td> 2211 <td>uleb128 <i>(optional)</i></td> 2212 <td>bytecode address of the catch-all handler. This element is only 2213 present if <code>size</code> is non-positive. 2214 </td> 2215 </tr> 2216 </tbody> 2217 </table> 2218 2219 <h3>encoded_type_addr_pair Format</h3> 2220 2221 <table class="format"> 2222 <thead> 2223 <tr> 2224 <th>Name</th> 2225 <th>Format</th> 2226 <th>Description</th> 2227 </tr> 2228 </thead> 2229 <tbody> 2230 <tr> 2231 <td>type_idx</td> 2232 <td>uleb128</td> 2233 <td>index into the <code>type_ids</code> list for the type of the 2234 exception to catch 2235 </td> 2236 </tr> 2237 <tr> 2238 <td>addr</td> 2239 <td>uleb128</td> 2240 <td>bytecode address of the associated exception handler</td> 2241 </tr> 2242 </tbody> 2243 </table> 2244 2245 <h3>debug_info_item</h3> 2246 <h4>referenced from code_item</h4> 2247 <h4>appears in the data section</h4> 2248 <h4>alignment: none (byte-aligned)</h4> 2249 2250 <p>Each <code>debug_info_item</code> defines a DWARF3-inspired byte-coded 2251 state machine that, when interpreted, emits the positions 2252 table and (potentially) the local variable information for a 2253 <code>code_item</code>. The sequence begins with a variable-length 2254 header (the length of which depends on the number of method 2255 parameters), is followed by the state machine bytecodes, and ends 2256 with an <code>DBG_END_SEQUENCE</code> byte.</p> 2257 2258 <p>The state machine consists of five registers. The 2259 <code>address</code> register represents the instruction offset in the 2260 associated <code>insns_item</code> in 16-bit code units. The 2261 <code>address</code> register starts at <code>0</code> at the beginning of each 2262 <code>debug_info</code> sequence and must only monotonically increase. 2263 The <code>line</code> register represents what source line number 2264 should be associated with the next positions table entry emitted by 2265 the state machine. It is initialized in the sequence header, and may 2266 change in positive or negative directions but must never be less than 2267 <code>1</code>. The <code>source_file</code> register represents the 2268 source file that the line number entries refer to. It is initialized to 2269 the value of <code>source_file_idx</code> in <code>class_def_item</code>. 2270 The other two variables, <code>prologue_end</code> and 2271 <code>epilogue_begin</code>, are boolean flags (initialized to 2272 <code>false</code>) that indicate whether the next position emitted 2273 should be considered a method prologue or epilogue. The state machine 2274 must also track the name and type of the last local variable live in 2275 each register for the <code>DBG_RESTART_LOCAL</code> code.</p> 2276 2277 <p>The header is as follows:</p> 2278 2279 <table class="format"> 2280 <thead> 2281 <tr> 2282 <th>Name</th> 2283 <th>Format</th> 2284 <th>Description</th> 2285 </tr> 2286 </thead> 2287 <tbody> 2288 <tr> 2289 <td>line_start</td> 2290 <td>uleb128</td> 2291 <td>the initial value for the state machine's <code>line</code> register. 2292 Does not represent an actual positions entry. 2293 </td> 2294 </tr> 2295 <tr> 2296 <td>parameters_size</td> 2297 <td>uleb128</td> 2298 <td>the number of parameter names that are encoded. There should be 2299 one per method parameter, excluding an instance method's <code>this</code>, 2300 if any. 2301 </td> 2302 </tr> 2303 <tr> 2304 <td>parameter_names</td> 2305 <td>uleb128p1[parameters_size]</td> 2306 <td>string index of the method parameter name. An encoded value of 2307 <code>NO_INDEX</code> indicates that no name 2308 is available for the associated parameter. The type descriptor 2309 and signature are implied from the method descriptor and signature. 2310 </td> 2311 </tr> 2312 </tbody> 2313 </table> 2314 2315 <p>The byte code values are as follows:</p> 2316 2317 <table class="debugByteCode"> 2318 <thead> 2319 <tr> 2320 <th>Name</th> 2321 <th>Value</th> 2322 <th>Format</th> 2323 <th>Arguments</th> 2324 <th>Description</th> 2325 </tr> 2326 </thead> 2327 <tbody> 2328 <tr> 2329 <td>DBG_END_SEQUENCE</td> 2330 <td>0x00</td> 2331 <td></td> 2332 <td><i>(none)</i></td> 2333 <td>terminates a debug info sequence for a <code>code_item</code></td> 2334 </tr> 2335 <tr> 2336 <td>DBG_ADVANCE_PC</td> 2337 <td>0x01</td> 2338 <td>uleb128 addr_diff</td> 2339 <td><code>addr_diff</code>: amount to add to address register</td> 2340 <td>advances the address register without emitting a positions entry</td> 2341 </tr> 2342 <tr> 2343 <td>DBG_ADVANCE_LINE</td> 2344 <td>0x02</td> 2345 <td>sleb128 line_diff</td> 2346 <td><code>line_diff</code>: amount to change line register by</td> 2347 <td>advances the line register without emitting a positions entry</td> 2348 </tr> 2349 <tr> 2350 <td>DBG_START_LOCAL</td> 2351 <td>0x03</td> 2352 <td>uleb128 register_num<br/> 2353 uleb128p1 name_idx<br/> 2354 uleb128p1 type_idx 2355 </td> 2356 <td><code>register_num</code>: register that will contain local<br/> 2357 <code>name_idx</code>: string index of the name<br/> 2358 <code>type_idx</code>: type index of the type 2359 </td> 2360 <td>introduces a local variable at the current address. Either 2361 <code>name_idx</code> or <code>type_idx</code> may be 2362 <code>NO_INDEX</code> to indicate that that value is unknown. 2363 </td> 2364 </tr> 2365 <tr> 2366 <td>DBG_START_LOCAL_EXTENDED</td> 2367 <td>0x04</td> 2368 <td>uleb128 register_num<br/> 2369 uleb128p1 name_idx<br/> 2370 uleb128p1 type_idx<br/> 2371 uleb128p1 sig_idx 2372 </td> 2373 <td><code>register_num</code>: register that will contain local<br/> 2374 <code>name_idx</code>: string index of the name<br/> 2375 <code>type_idx</code>: type index of the type<br/> 2376 <code>sig_idx</code>: string index of the type signature 2377 </td> 2378 <td>introduces a local with a type signature at the current address. 2379 Any of <code>name_idx</code>, <code>type_idx</code>, or 2380 <code>sig_idx</code> may be <code>NO_INDEX</code> 2381 to indicate that that value is unknown. (If <code>sig_idx</code> is 2382 <code>-1</code>, though, the same data could be represented more 2383 efficiently using the opcode <code>DBG_START_LOCAL</code>.) 2384 <p><b>Note:</b> See the discussion under 2385 "<code>dalvik.annotation.Signature</code>" below for caveats about 2386 handling signatures.</p> 2387 </td> 2388 </tr> 2389 <tr> 2390 <td>DBG_END_LOCAL</td> 2391 <td>0x05</td> 2392 <td>uleb128 register_num</td> 2393 <td><code>register_num</code>: register that contained local</td> 2394 <td>marks a currently-live local variable as out of scope at the current 2395 address 2396 </td> 2397 </tr> 2398 <tr> 2399 <td>DBG_RESTART_LOCAL</td> 2400 <td>0x06</td> 2401 <td>uleb128 register_num</td> 2402 <td><code>register_num</code>: register to restart</td> 2403 <td>re-introduces a local variable at the current address. The name 2404 and type are the same as the last local that was live in the specified 2405 register. 2406 </td> 2407 </tr> 2408 <tr> 2409 <td>DBG_SET_PROLOGUE_END</td> 2410 <td>0x07</td> 2411 <td></td> 2412 <td><i>(none)</i></td> 2413 <td>sets the <code>prologue_end</code> state machine register, 2414 indicating that the next position entry that is added should be 2415 considered the end of a method prologue (an appropriate place for 2416 a method breakpoint). The <code>prologue_end</code> register is 2417 cleared by any special (<code>>= 0x0a</code>) opcode. 2418 </td> 2419 </tr> 2420 <tr> 2421 <td>DBG_SET_EPILOGUE_BEGIN</td> 2422 <td>0x08</td> 2423 <td></td> 2424 <td><i>(none)</i></td> 2425 <td>sets the <code>epilogue_begin</code> state machine register, 2426 indicating that the next position entry that is added should be 2427 considered the beginning of a method epilogue (an appropriate place 2428 to suspend execution before method exit). 2429 The <code>epilogue_begin</code> register is cleared by any special 2430 (<code>>= 0x0a</code>) opcode. 2431 </td> 2432 </tr> 2433 <tr> 2434 <td>DBG_SET_FILE</td> 2435 <td>0x09</td> 2436 <td>uleb128p1 name_idx</td> 2437 <td><code>name_idx</code>: string index of source file name; 2438 <code>NO_INDEX</code> if unknown 2439 </td> 2440 <td>indicates that all subsequent line number entries make reference to this 2441 source file name, instead of the default name specified in 2442 <code>code_item</code> 2443 </td> 2444 </tr> 2445 <tr> 2446 <td><i>Special Opcodes</i></td> 2447 <!-- When updating the range below, make sure to search for other 2448 instances of 0x0a in this section. --> 2449 <td>0x0a…0xff</td> 2450 <td></td> 2451 <td><i>(none)</i></td> 2452 <td>advances the <code>line</code> and <code>address</code> registers, 2453 emits a position entry, and clears <code>prologue_end</code> and 2454 <code>epilogue_begin</code>. See below for description. 2455 </td> 2456 </tr> 2457 </tbody> 2458 </table> 2459 2460 <h3>Special Opcodes</h3> 2461 2462 <p>Opcodes with values between <code>0x0a</code> and <code>0xff</code> 2463 (inclusive) move both the <code>line</code> and <code>address</code> 2464 registers by a small amount and then emit a new position table entry. 2465 The formula for the increments are as follows:</p> 2466 2467 <pre> 2468 DBG_FIRST_SPECIAL = 0x0a // the smallest special opcode 2469 DBG_LINE_BASE = -4 // the smallest line number increment 2470 DBG_LINE_RANGE = 15 // the number of line increments represented 2471 2472 adjusted_opcode = opcode - DBG_FIRST_SPECIAL 2473 2474 line += DBG_LINE_BASE + (adjusted_opcode % DBG_LINE_RANGE) 2475 address += (adjusted_opcode / DBG_LINE_RANGE) 2476 </pre> 2477 2478 <h3>annotations_directory_item</h3> 2479 <h4>referenced from class_def_item</h4> 2480 <h4>appears in the data section</h4> 2481 <h4>alignment: 4 bytes</h4> 2482 2483 <table class="format"> 2484 <thead> 2485 <tr> 2486 <th>Name</th> 2487 <th>Format</th> 2488 <th>Description</th> 2489 </tr> 2490 </thead> 2491 <tbody> 2492 <tr> 2493 <td>class_annotations_off</td> 2494 <td>uint</td> 2495 <td>offset from the start of the file to the annotations made directly 2496 on the class, or <code>0</code> if the class has no direct annotations. 2497 The offset, if non-zero, should be to a location in the 2498 <code>data</code> section. The format of the data is specified 2499 by "<code>annotation_set_item</code>" below. 2500 </td> 2501 </tr> 2502 <tr> 2503 <td>fields_size</td> 2504 <td>uint</td> 2505 <td>count of fields annotated by this item</td> 2506 </tr> 2507 <tr> 2508 <td>annotated_methods_size</td> 2509 <td>uint</td> 2510 <td>count of methods annotated by this item</td> 2511 </tr> 2512 <tr> 2513 <td>annotated_parameters_size</td> 2514 <td>uint</td> 2515 <td>count of method parameter lists annotated by this item</td> 2516 </tr> 2517 <tr> 2518 <td>field_annotations</td> 2519 <td>field_annotation[fields_size] <i>(optional)</i></td> 2520 <td>list of associated field annotations. The elements of the list must 2521 be sorted in increasing order, by <code>field_idx</code>. 2522 </td> 2523 </tr> 2524 <tr> 2525 <td>method_annotations</td> 2526 <td>method_annotation[methods_size] <i>(optional)</i></td> 2527 <td>list of associated method annotations. The elements of the list must 2528 be sorted in increasing order, by <code>method_idx</code>. 2529 </td> 2530 </tr> 2531 <tr> 2532 <td>parameter_annotations</td> 2533 <td>parameter_annotation[parameters_size] <i>(optional)</i></td> 2534 <td>list of associated method parameter annotations. The elements of the 2535 list must be sorted in increasing order, by <code>method_idx</code>. 2536 </td> 2537 </tr> 2538 </tbody> 2539 </table> 2540 2541 <p><b>Note:</b> All elements' <code>field_id</code>s and 2542 <code>method_id</code>s must refer to the same defining class.</p> 2543 2544 <h3>field_annotation Format</h3> 2545 2546 <table class="format"> 2547 <thead> 2548 <tr> 2549 <th>Name</th> 2550 <th>Format</th> 2551 <th>Description</th> 2552 </tr> 2553 </thead> 2554 <tbody> 2555 <tr> 2556 <td>field_idx</td> 2557 <td>uint</td> 2558 <td>index into the <code>field_ids</code> list for the identity of the 2559 field being annotated 2560 </td> 2561 </tr> 2562 <tr> 2563 <td>annotations_off</td> 2564 <td>uint</td> 2565 <td>offset from the start of the file to the list of annotations for 2566 the field. The offset should be to a location in the <code>data</code> 2567 section. The format of the data is specified by 2568 "<code>annotation_set_item</code>" below. 2569 </td> 2570 </tr> 2571 </tbody> 2572 </table> 2573 2574 <h3>method_annotation Format</h3> 2575 2576 <table class="format"> 2577 <thead> 2578 <tr> 2579 <th>Name</th> 2580 <th>Format</th> 2581 <th>Description</th> 2582 </tr> 2583 </thead> 2584 <tbody> 2585 <tr> 2586 <td>method_idx</td> 2587 <td>uint</td> 2588 <td>index into the <code>method_ids</code> list for the identity of the 2589 method being annotated 2590 </td> 2591 </tr> 2592 <tr> 2593 <td>annotations_off</td> 2594 <td>uint</td> 2595 <td>offset from the start of the file to the list of annotations for 2596 the method. The offset should be to a location in the 2597 <code>data</code> section. The format of the data is specified by 2598 "<code>annotation_set_item</code>" below. 2599 </td> 2600 </tr> 2601 </tbody> 2602 </table> 2603 2604 <h3>parameter_annotation Format</h3> 2605 2606 <table class="format"> 2607 <thead> 2608 <tr> 2609 <th>Name</th> 2610 <th>Format</th> 2611 <th>Description</th> 2612 </tr> 2613 </thead> 2614 <tbody> 2615 <tr> 2616 <td>method_idx</td> 2617 <td>uint</td> 2618 <td>index into the <code>method_ids</code> list for the identity of the 2619 method whose parameters are being annotated 2620 </td> 2621 </tr> 2622 <tr> 2623 <td>annotations_off</td> 2624 <td>uint</td> 2625 <td>offset from the start of the file to the list of annotations for 2626 the method parameters. The offset should be to a location in the 2627 <code>data</code> section. The format of the data is specified by 2628 "<code>annotation_set_ref_list</code>" below. 2629 </td> 2630 </tr> 2631 </tbody> 2632 </table> 2633 2634 <h3>annotation_set_ref_list</h3> 2635 <h4>referenced from parameter_annotations_item</h4> 2636 <h4>appears in the data section</h4> 2637 <h4>alignment: 4 bytes</h4> 2638 2639 <table class="format"> 2640 <thead> 2641 <tr> 2642 <th>Name</th> 2643 <th>Format</th> 2644 <th>Description</th> 2645 </tr> 2646 </thead> 2647 <tbody> 2648 <tr> 2649 <td>size</td> 2650 <td>uint</td> 2651 <td>size of the list, in entries</td> 2652 </tr> 2653 <tr> 2654 <td>list</td> 2655 <td>annotation_set_ref_item[size]</td> 2656 <td>elements of the list</td> 2657 </tr> 2658 </tbody> 2659 </table> 2660 2661 <h3>annotation_set_ref_item Format</h3> 2662 2663 <table class="format"> 2664 <thead> 2665 <tr> 2666 <th>Name</th> 2667 <th>Format</th> 2668 <th>Description</th> 2669 </tr> 2670 </thead> 2671 <tbody> 2672 <tr> 2673 <td>annotations_off</td> 2674 <td>uint</td> 2675 <td>offset from the start of the file to the referenced annotation set 2676 or <code>0</code> if there are no annotations for this element. 2677 The offset, if non-zero, should be to a location in the <code>data</code> 2678 section. The format of the data is specified by 2679 "<code>annotation_set_item</code>" below. 2680 </td> 2681 </tr> 2682 </tbody> 2683 </table> 2684 2685 <h3>annotation_set_item</h3> 2686 <h4>referenced from annotations_directory_item, field_annotations_item, 2687 method_annotations_item, and annotation_set_ref_item</h4> 2688 <h4>appears in the data section</h4> 2689 <h4>alignment: 4 bytes</h4> 2690 2691 <table class="format"> 2692 <thead> 2693 <tr> 2694 <th>Name</th> 2695 <th>Format</th> 2696 <th>Description</th> 2697 </tr> 2698 </thead> 2699 <tbody> 2700 <tr> 2701 <td>size</td> 2702 <td>uint</td> 2703 <td>size of the set, in entries</td> 2704 </tr> 2705 <tr> 2706 <td>entries</td> 2707 <td>annotation_off_item[size]</td> 2708 <td>elements of the set. The elements must be sorted in increasing order, 2709 by <code>type_idx</code>. 2710 </td> 2711 </tr> 2712 </tbody> 2713 </table> 2714 2715 <h3>annotation_off_item Format</h3> 2716 2717 <table class="format"> 2718 <thead> 2719 <tr> 2720 <th>Name</th> 2721 <th>Format</th> 2722 <th>Description</th> 2723 </tr> 2724 </thead> 2725 <tbody> 2726 <tr> 2727 <td>annotation_off</td> 2728 <td>uint</td> 2729 <td>offset from the start of the file to an annotation. 2730 The offset should be to a location in the <code>data</code> section, 2731 and the format of the data at that location is specified by 2732 "<code>annotation_item</code>" below. 2733 </td> 2734 </tr> 2735 </tbody> 2736 </table> 2737 2738 2739 <h3>annotation_item</h3> 2740 <h4>referenced from annotation_set_item</h4> 2741 <h4>appears in the data section</h4> 2742 <h4>alignment: none (byte-aligned)</h4> 2743 2744 <table class="format"> 2745 <thead> 2746 <tr> 2747 <th>Name</th> 2748 <th>Format</th> 2749 <th>Description</th> 2750 </tr> 2751 </thead> 2752 <tbody> 2753 <tr> 2754 <td>visibility</td> 2755 <td>ubyte</td> 2756 <td>intended visibility of this annotation (see below)</td> 2757 </tr> 2758 <tr> 2759 <td>annotation</td> 2760 <td>encoded_annotation</td> 2761 <td>encoded annotation contents, in the format described by 2762 "<code>encoded_annotation</code> Format" under 2763 "<code>encoded_value</code> Encoding" above. 2764 </td> 2765 </tr> 2766 </tbody> 2767 </table> 2768 2769 <h3>Visibility values</h3> 2770 2771 <p>These are the options for the <code>visibility</code> field in an 2772 <code>annotation_item</code>:</p> 2773 2774 <table class="format"> 2775 <thead> 2776 <tr> 2777 <th>Name</th> 2778 <th>Value</th> 2779 <th>Description</th> 2780 </tr> 2781 </thead> 2782 <tbody> 2783 <tr> 2784 <td>VISIBILITY_BUILD</td> 2785 <td>0x00</td> 2786 <td>intended only to be visible at build time (e.g., during compilation 2787 of other code) 2788 </td> 2789 </tr> 2790 <tr> 2791 <td>VISIBILITY_RUNTIME</td> 2792 <td>0x01</td> 2793 <td>intended to visible at runtime</td> 2794 </tr> 2795 <tr> 2796 <td>VISIBILITY_SYSTEM</td> 2797 <td>0x02</td> 2798 <td>intended to visible at runtime, but only to the underlying system 2799 (and not to regular user code) 2800 </td> 2801 </tr> 2802 </tbody> 2803 </table> 2804 2805 <h3>encoded_array_item</h3> 2806 <h4>referenced from class_def_item</h4> 2807 <h4>appears in the data section</h4> 2808 <h4>alignment: none (byte-aligned)</h4> 2809 2810 <table class="format"> 2811 <thead> 2812 <tr> 2813 <th>Name</th> 2814 <th>Format</th> 2815 <th>Description</th> 2816 </tr> 2817 </thead> 2818 <tbody> 2819 <tr> 2820 <td>value</td> 2821 <td>encoded_array</td> 2822 <td>bytes representing the encoded array value, in the format specified 2823 by "<code>encoded_array</code> Format" under "<code>encoded_value</code> 2824 Encoding" above. 2825 </td> 2826 </tr> 2827 </tbody> 2828 </table> 2829 2830 <h2>System Annotations</h2> 2831 2832 <p>System annotations are used to represent various pieces of reflective 2833 information about classes (and methods and fields). This information is 2834 generally only accessed indirectly by client (non-system) code.</p> 2835 2836 <p>System annotations are represented in <code>.dex</code> files as 2837 annotations with visibility set to <code>VISIBILITY_SYSTEM</code>. 2838 2839 <h3>dalvik.annotation.AnnotationDefault</h3> 2840 <h4>appears on methods in annotation interfaces</h4> 2841 2842 <p>An <code>AnnotationDefault</code> annotation is attached to each 2843 annotation interface which wishes to indicate default bindings.</p> 2844 2845 <table class="format"> 2846 <thead> 2847 <tr> 2848 <th>Name</th> 2849 <th>Format</th> 2850 <th>Description</th> 2851 </tr> 2852 </thead> 2853 <tbody> 2854 <tr> 2855 <td>value</td> 2856 <td>Annotation</td> 2857 <td>the default bindings for this annotation, represented as an annotation 2858 of this type. The annotation need not include all names defined by the 2859 annotation; missing names simply do not have defaults. 2860 </td> 2861 </tr> 2862 </tbody> 2863 </table> 2864 2865 <h3>dalvik.annotation.EnclosingClass</h3> 2866 <h4>appears on classes</h4> 2867 2868 <p>An <code>EnclosingClass</code> annotation is attached to each class 2869 which is either defined as a member of another class, per se, or is 2870 anonymous but not defined within a method body (e.g., a synthetic 2871 inner class). Every class that has this annotation must also have an 2872 <code>InnerClass</code> annotation. Additionally, a class must not have 2873 both an <code>EnclosingClass</code> and an 2874 <code>EnclosingMethod</code> annotation.</p> 2875 2876 <table class="format"> 2877 <thead> 2878 <tr> 2879 <th>Name</th> 2880 <th>Format</th> 2881 <th>Description</th> 2882 </tr> 2883 </thead> 2884 <tbody> 2885 <tr> 2886 <td>value</td> 2887 <td>Class</td> 2888 <td>the class which most closely lexically scopes this class</td> 2889 </tr> 2890 </tbody> 2891 </table> 2892 2893 <h3>dalvik.annotation.EnclosingMethod</h3> 2894 <h4>appears on classes</h4> 2895 2896 <p>An <code>EnclosingMethod</code> annotation is attached to each class 2897 which is defined inside a method body. Every class that has this 2898 annotation must also have an <code>InnerClass</code> annotation. 2899 Additionally, a class must not have both an <code>EnclosingClass</code> 2900 and an <code>EnclosingMethod</code> annotation.</p> 2901 2902 <table class="format"> 2903 <thead> 2904 <tr> 2905 <th>Name</th> 2906 <th>Format</th> 2907 <th>Description</th> 2908 </tr> 2909 </thead> 2910 <tbody> 2911 <tr> 2912 <td>value</td> 2913 <td>Method</td> 2914 <td>the method which most closely lexically scopes this class</td> 2915 </tr> 2916 </tbody> 2917 </table> 2918 2919 <h3>dalvik.annotation.InnerClass</h3> 2920 <h4>appears on classes</h4> 2921 2922 <p>An <code>InnerClass</code> annotation is attached to each class 2923 which is defined in the lexical scope of another class's definition. 2924 Any class which has this annotation must also have <i>either</i> an 2925 <code>EnclosingClass</code> annotation <i>or</i> an 2926 <code>EnclosingMethod</code> annotation.</p> 2927 2928 <table class="format"> 2929 <thead> 2930 <tr> 2931 <th>Name</th> 2932 <th>Format</th> 2933 <th>Description</th> 2934 </tr> 2935 </thead> 2936 <tbody> 2937 <tr> 2938 <td>name</td> 2939 <td>String</td> 2940 <td>the originally declared simple name of this class (not including any 2941 package prefix). If this class is anonymous, then the name is 2942 <code>null</code>. 2943 </td> 2944 </tr> 2945 <tr> 2946 <td>accessFlags</td> 2947 <td>int</td> 2948 <td>the originally declared access flags of the class (which may differ 2949 from the effective flags because of a mismatch between the execution 2950 models of the source language and target virtual machine) 2951 </td> 2952 </tr> 2953 </tbody> 2954 </table> 2955 2956 <h3>dalvik.annotation.MemberClasses</h3> 2957 <h4>appears on classes</h4> 2958 2959 <p>A <code>MemberClasses</code> annotation is attached to each class 2960 which declares member classes. (A member class is a direct inner class 2961 that has a name.)</p> 2962 2963 <table class="format"> 2964 <thead> 2965 <tr> 2966 <th>Name</th> 2967 <th>Format</th> 2968 <th>Description</th> 2969 </tr> 2970 </thead> 2971 <tbody> 2972 <tr> 2973 <td>value</td> 2974 <td>Class[]</td> 2975 <td>array of the member classes</td> 2976 </tr> 2977 </tbody> 2978 </table> 2979 2980 <h3>dalvik.annotation.Signature</h3> 2981 <h4>appears on classes, fields, and methods</h4> 2982 2983 <p>A <code>Signature</code> annotation is attached to each class, 2984 field, or method which is defined in terms of a more complicated type 2985 than is representable by a <code>type_id_item</code>. The 2986 <code>.dex</code> format does not define the format for signatures; it 2987 is merely meant to be able to represent whatever signatures a source 2988 language requires for successful implementation of that language's 2989 semantics. As such, signatures are not generally parsed (or verified) 2990 by virtual machine implementations. The signatures simply get handed 2991 off to higher-level APIs and tools (such as debuggers). Any use of a 2992 signature, therefore, should be written so as not to make any 2993 assumptions about only receiving valid signatures, explicitly guarding 2994 itself against the possibility of coming across a syntactically 2995 invalid signature.</p> 2996 2997 <p>Because signature strings tend to have a lot of duplicated content, 2998 a <code>Signature</code> annotation is defined as an <i>array</i> of 2999 strings, where duplicated elements naturally refer to the same 3000 underlying data, and the signature is taken to be the concatenation of 3001 all the strings in the array. There are no rules about how to pull 3002 apart a signature into separate strings; that is entirely up to the 3003 tools that generate <code>.dex</code> files.</p> 3004 3005 <table class="format"> 3006 <thead> 3007 <tr> 3008 <th>Name</th> 3009 <th>Format</th> 3010 <th>Description</th> 3011 </tr> 3012 </thead> 3013 <tbody> 3014 <tr> 3015 <td>value</td> 3016 <td>String[]</td> 3017 <td>the signature of this class or member, as an array of strings that 3018 is to be concatenated together</td> 3019 </tr> 3020 </tbody> 3021 </table> 3022 3023 <h3>dalvik.annotation.Throws</h3> 3024 <h4>appears on methods</h4> 3025 3026 <p>A <code>Throws</code> annotation is attached to each method which is 3027 declared to throw one or more exception types.</p> 3028 3029 <table class="format"> 3030 <thead> 3031 <tr> 3032 <th>Name</th> 3033 <th>Format</th> 3034 <th>Description</th> 3035 </tr> 3036 </thead> 3037 <tbody> 3038 <tr> 3039 <td>value</td> 3040 <td>Class[]</td> 3041 <td>the array of exception types thrown</td> 3042 </tr> 3043 </tbody> 3044 </table> 3045
