本文记录一个分析dex文件格式的例子，供参考。
源码
1 public class Demo
2 {
3 public static void myLog(String tag, String str)
4 {
5 System.out.printf(tag + ": " + str + "\n");
6 }
7
8 public static void main(String[] argc)
9 {
10 myLog("myLog","Hello World!");
11 }
12 }
生成dex文件
➜ apk-demo ls
Demo.java
➜ apk-demo javac Demo.java
➜ apk-demo ls
Demo.class Demo.java
➜ apk-demo dx --dex --output=classes.dex Demo.class
➜ apk-demo ls
classes.dex Demo.class Demo.java
完整的classes.dex
hexdump -C classes.dex
00000000 64 65 78 0a 30 33 35 00 a7 83 a6 ef 32 77 c2 ea |dex.035.....2w..|
00000010 3a 2c 23 63 31 b4 16 b3 6e ba 6e 64 f7 4e dd 31 |:,#c1...n.nd.N.1|
00000020 30 04 00 00 70 00 00 00 78 56 34 12 00 00 00 00 |0...p...xV4.....|
00000030 00 00 00 00 90 03 00 00 19 00 00 00 70 00 00 00 |............p...|
00000040 09 00 00 00 d4 00 00 00 06 00 00 00 f8 00 00 00 |................|
00000050 01 00 00 00 40 01 00 00 08 00 00 00 48 01 00 00 |....@.......H...|
00000060 01 00 00 00 88 01 00 00 88 02 00 00 a8 01 00 00 |................|
00000070 5a 02 00 00 5d 02 00 00 61 02 00 00 69 02 00 00 |Z...]...a...i...|
00000080 74 02 00 00 82 02 00 00 85 02 00 00 8d 02 00 00 |t...............|
00000090 91 02 00 00 96 02 00 00 ad 02 00 00 c1 02 00 00 |................|
000000a0 d5 02 00 00 f0 02 00 00 04 03 00 00 07 03 00 00 |................|
000000b0 0b 03 00 00 10 03 00 00 25 03 00 00 3a 03 00 00 |........%...:...|
000000c0 42 03 00 00 48 03 00 00 4f 03 00 00 54 03 00 00 |B...H...O...T...|
000000d0 5c 03 00 00 06 00 00 00 09 00 00 00 0a 00 00 00 |\...............|
000000e0 0b 00 00 00 0c 00 00 00 0d 00 00 00 0e 00 00 00 |................|
000000f0 11 00 00 00 12 00 00 00 08 00 00 00 01 00 00 00 |................|
00000100 3c 02 00 00 05 00 00 00 03 00 00 00 00 00 00 00 |<...............|
00000110 07 00 00 00 04 00 00 00 44 02 00 00 0e 00 00 00 |........D.......|
00000120 06 00 00 00 00 00 00 00 10 00 00 00 06 00 00 00 |................|
00000130 4c 02 00 00 0f 00 00 00 06 00 00 00 54 02 00 00 |L...........T...|
00000140 05 00 01 00 16 00 00 00 00 00 03 00 02 00 00 00 |................|
00000150 00 00 05 00 14 00 00 00 00 00 04 00 15 00 00 00 |................|
00000160 01 00 00 00 17 00 00 00 02 00 03 00 02 00 00 00 |................|
00000170 04 00 03 00 02 00 00 00 04 00 02 00 13 00 00 00 |................|
00000180 04 00 01 00 18 00 00 00 00 00 00 00 01 00 00 00 |................|
00000190 02 00 00 00 00 00 00 00 03 00 00 00 00 00 00 00 |................|
000001a0 7c 03 00 00 00 00 00 00 01 00 01 00 01 00 00 00 ||...............|
000001b0 66 03 00 00 04 00 00 00 70 10 04 00 00 00 0e 00 |f.......p.......|
000001c0 03 00 01 00 02 00 00 00 6b 03 00 00 08 00 00 00 |........k.......|
000001d0 1a 00 15 00 1a 01 04 00 71 20 02 00 10 00 0e 00 |........q ......|
000001e0 05 00 02 00 03 00 00 00 72 03 00 00 26 00 00 00 |........r...&...|
000001f0 62 00 00 00 22 01 04 00 70 10 05 00 01 00 6e 20 |b..."...p.....n |
00000200 06 00 31 00 0c 01 1a 02 01 00 6e 20 06 00 21 00 |..1.......n ..!.|
00000210 0c 01 6e 20 06 00 41 00 0c 01 1a 02 00 00 6e 20 |..n ..A.......n |
00000220 06 00 21 00 0c 01 6e 10 07 00 01 00 0c 01 12 02 |..!...n.........|
00000230 23 22 07 00 6e 30 03 00 10 02 0e 00 02 00 00 00 |#"..n0..........|
00000240 03 00 07 00 01 00 00 00 03 00 00 00 02 00 00 00 |................|
00000250 03 00 03 00 01 00 00 00 08 00 01 0a 00 02 3a 20 |..............: |
00000260 00 06 3c 69 6e 69 74 3e 00 09 44 65 6d 6f 2e 6a |..<init>..Demo.j|
00000270 61 76 61 00 0c 48 65 6c 6c 6f 20 57 6f 72 6c 64 |ava..Hello World|
00000280 21 00 01 4c 00 06 4c 44 65 6d 6f 3b 00 02 4c 4c |!..L..LDemo;..LL|
00000290 00 03 4c 4c 4c 00 15 4c 6a 61 76 61 2f 69 6f 2f |..LLL..Ljava/io/|
000002a0 50 72 69 6e 74 53 74 72 65 61 6d 3b 00 12 4c 6a |PrintStream;..Lj|
000002b0 61 76 61 2f 6c 61 6e 67 2f 4f 62 6a 65 63 74 3b |ava/lang/Object;|
000002c0 00 12 4c 6a 61 76 61 2f 6c 61 6e 67 2f 53 74 72 |..Ljava/lang/Str|
000002d0 69 6e 67 3b 00 19 4c 6a 61 76 61 2f 6c 61 6e 67 |ing;..Ljava/lang|
000002e0 2f 53 74 72 69 6e 67 42 75 69 6c 64 65 72 3b 00 |/StringBuilder;.|
000002f0 12 4c 6a 61 76 61 2f 6c 61 6e 67 2f 53 79 73 74 |.Ljava/lang/Syst|
00000300 65 6d 3b 00 01 56 00 02 56 4c 00 03 56 4c 4c 00 |em;..V..VL..VLL.|
00000310 13 5b 4c 6a 61 76 61 2f 6c 61 6e 67 2f 4f 62 6a |.[Ljava/lang/Obj|
00000320 65 63 74 3b 00 13 5b 4c 6a 61 76 61 2f 6c 61 6e |ect;..[Ljava/lan|
00000330 67 2f 53 74 72 69 6e 67 3b 00 06 61 70 70 65 6e |g/String;..appen|
00000340 64 00 04 6d 61 69 6e 00 05 6d 79 4c 6f 67 00 03 |d..main..myLog..|
00000350 6f 75 74 00 06 70 72 69 6e 74 66 00 08 74 6f 53 |out..printf..toS|
00000360 74 72 69 6e 67 00 01 00 07 0e 00 0a 01 00 07 0e |tring...........|
00000370 78 00 05 02 00 00 07 0e 01 25 0f 00 00 00 03 00 |x........%......|
00000380 00 81 80 04 a8 03 01 09 c0 03 01 09 e0 03 00 00 |................|
00000390 0d 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 |................|
000003a0 01 00 00 00 19 00 00 00 70 00 00 00 02 00 00 00 |........p.......|
000003b0 09 00 00 00 d4 00 00 00 03 00 00 00 06 00 00 00 |................|
000003c0 f8 00 00 00 04 00 00 00 01 00 00 00 40 01 00 00 |............@...|
000003d0 05 00 00 00 08 00 00 00 48 01 00 00 06 00 00 00 |........H.......|
000003e0 01 00 00 00 88 01 00 00 01 20 00 00 03 00 00 00 |......... ......|
000003f0 a8 01 00 00 01 10 00 00 04 00 00 00 3c 02 00 00 |............<...|
00000400 02 20 00 00 19 00 00 00 5a 02 00 00 03 20 00 00 |. ......Z.... ..|
00000410 03 00 00 00 66 03 00 00 00 20 00 00 01 00 00 00 |....f.... ......|
00000420 7c 03 00 00 00 10 00 00 01 00 00 00 90 03 00 00 ||...............|
00000430
文件内容大体划分
类
类的定义
343 /*
344 * Direct-mapped "class_def_item".
345 */
346 struct DexClassDef {
347 u4 classIdx; /* index into typeIds for this class */
348 u4 accessFlags;
349 u4 superclassIdx; /* index into typeIds for superclass */
350 u4 interfacesOff; /* file offset to DexTypeList */
351 u4 sourceFileIdx; /* index into stringIds for source file name */
352 u4 annotationsOff; /* file offset to annotations_directory_item */
353 u4 classDataOff; /* file offset to class_data_item */
354 u4 staticValuesOff; /* file offset to DexEncodedArray */
355 };
309 /*
310 * Direct-mapped "type_id_item".
311 */
312 struct DexTypeId {
313 u4 descriptorIdx; /* index into stringIds list for type descriptor */
314 };
表：类
| classIdx | 0x00 | typeIds = 0x06 | stringIds = 0x285 | string_data_item = 06 4c 44 65 6d 6f 3b 00 | LDemo; |
| accessFlags | 0x01 | public | |||
| superclassIdx | 0x02 | typeIds = 0x0a | stringIds = 0x02ad | string_data_item = 12 4c 6a 61 76 61 2f 6c 61 6e 67 2f 4f 62 6a 65 63 74 3b 00 | Ljava/lang/Object; |
| interfacesOff | 0x00 | 没有接口 | |||
| sourceFileIdx | 0x03 | stringIds = 0x269 | string_data_item = 09 44 65 6d 6f 2e 6a 61 76 61 00 | Demo.java | |
| annotationsOff | 0x00 | 这个类没有注释 | |||
| classDataOff | 0x37c | class_data_item的偏移量 | |||
| staticValuesOff | 0x00 | 这个类没有静态段 |
class_data_item 解析
表：class_data_item定义
| Name | Format | Description |
|---|---|---|
| static_fields_size | uleb128 | the number of static fields defined in this item |
| instance_fields_size | uleb128 | the number of instance fields defined in this item |
| direct_methods_size | uleb128 | the number of direct methods defined in this item |
| virtual_methods_size | uleb128 | the number of virtual methods defined in this item |
| static_fields | encoded_field[static_fields_size] | the defined static fields, represented as a sequence of encoded elements. The fields must be sorted by field_idx in increasing order. |
| instance_fields | encoded_field[instance_fields_size] | the defined instance fields, represented as a sequence of encoded elements. The fields must be sorted by field_idx in increasing order. |
| direct_methods | encoded_method[direct_methods_size] | the defined direct (any of static, private, or constructor) methods, represented as a sequence of encoded elements. The methods must be sorted by method_idx in increasing order. |
| virtual_methods | encoded_method[virtual_methods_size] | the defined virtual (none of static, private, or constructor) methods, represented as a sequence of encoded elements. This list should not include inherited methods unless overridden by the class that this item represents. The methods must be sorted by method_idx in increasing order. The method_idx of a virtual method must not be the same as any direct method. |
表：class_data_item
从0x37c开始。
0000037c 00 00 03 00 |x........%......|
00000380 00 81 80 04 a8 03 01 09 c0 03 01 09 e0 03 00 00 |................|
| Name | Format | value | description |
|---|---|---|---|
| static_fields_size | uleb128 | 00 | |
| instance_fields_size | uleb128 | 00 | |
| direct_methods_size | uleb128 | 03 | |
| virtual_methods_size | uleb128 | 00 | |
| static_fields | encoded_field[static_fields_size] | 无 | |
| instance_fields | encoded_field[instance_fields_size] | 无 | |
| direct_methods | encoded_method[direct_methods_size] | 00 81 80 04 a8 03 01 09 c0 03 01 09 e0 03 | |
| virtual_methods | encoded_method[virtual_methods_size] | 无 |
encoded_method解析
表：encoded_method定义
| Name | Format | Description |
|---|---|---|
| method_idx_diff | uleb128 | index into the method_ids list for the identity of this method (includes the name and descriptor), represented as a difference from the index of previous element in the list. The index of the first element in a list is represented directly. |
| access_flags | uleb128 | access flags for the method (public, final, etc.). See “access_flags Definitions” for details. |
| code_off | uleb128 | offset from the start of the file to the code structure for this method, or 0 if this method is either abstract or native. The offset should be to a location in the data section. The format of the data is specified by “code_item” below. |
表：direct_methods
| direct_methods | value |
|---|---|
| direct_method[0] | 00 81 80 04 a8 03 |
| direct_method[1] | 01 09 c0 03 |
| direct_method[2] | 01 09 e0 03 |
表：direct_method[0]
| method_idx_diff | access_flags | code_off |
|---|---|---|
| 00 | 81 80 04 | a8 03 |
| 0 | 0x1001 | 0x1a8 |
| <init> | ACC_CONSTRUCTOR|ACC_PUBLIC | code_item的偏移地址 |
表：direct_method[1]
| method_idx_diff | access_flags | code_off |
|---|---|---|
| 01 | 09 | c0 03 |
| 1 | 0x09 | 0x1c0 |
| main | ACC_STATIC|ACC_PUBLIC | code_item的偏移地址 |
表：direct_method[2]
| method_idx_diff | access_flags | code_off |
|---|---|---|
| 01 | 09 | e0 03 |
| 1 | 0x09 | 0x1e0 |
| main | ACC_STATIC|ACC_PUBLIC | code_item的偏移地址 |
注意：这里的main为什么会显示有两个？所有的static方法，到dex中都会是main。public static void main(String[] argc)始终放在<init>函数后面，所以它会被当做入口函数。多少个static函数就会产生对应多的包含01 09的encoded_method。
下面解析code_item，具体的定义结构在官网中有说明。
以下是尼古拉斯.赵四的翻译：
(1) registers_size：本段代码使用到的寄存器数目。
(2) ins_size：method传入参数的数目 。
(3) outs_size： 本段代码调用其它method 时需要的参数个数 。
(4) tries_size： try_item 结构的个数 。
(5) debug_off：偏移地址 ，指向本段代码的 debug 信息存放位置 ，是一个 debug_info_item 结构。
(6) insns_size：指令列表的大小 ，以 16-bit 为单位 。 insns 是 instructions 的缩写 。
(7) padding：值为 0 ，用于对齐字节 。
(8) tries 和 handlers：用于处理 java 中的 exception , 常见的语法有 try catch 。
code_item解析
direct_method[1]的code_item。
000001c0 03 00 01 00 02 00 00 00 6b 03 00 00 08 00 00 00 |........k.......|
000001d0 1a 00 15 00 1a 01 04 00 71 20 02 00 10 00 0e 00 |........q ......|
| Name | Format | value |
|---|---|---|
| registers_size | ushort | 0x03 |
| ins_size | ushort | 0x01 |
| outs_size | ushort | 0x02 |
| tries_size | ushort | 0x00 |
| debug_info_off | uint | 0x36b |
| insns_size | uint | 0x08 |
| insns | ushort[insns_size] | 1a 00 15 00 1a 01 04 00 71 20 02 00 10 00 0e 00 |
| padding | ushort (optional) = 0 | tries_size == 0 或者 insns_size 不是奇数(odd)，所以这项为空 |
| tries | try_item[tries_size] (optional) | 空 |
| handlers | encoded_catch_handler_list (optional) | 空 |
direct_method[2]的code_item
000001e0 05 00 02 00 03 00 00 00 72 03 00 00 26 00 00 00 |........r...&...|
000001f0 62 00 00 00 22 01 04 00 70 10 05 00 01 00 6e 20 |b..."...p.....n |
00000200 06 00 31 00 0c 01 1a 02 01 00 6e 20 06 00 21 00 |..1.......n ..!.|
00000210 0c 01 6e 20 06 00 41 00 0c 01 1a 02 00 00 6e 20 |..n ..A.......n |
00000220 06 00 21 00 0c 01 6e 10 07 00 01 00 0c 01 12 02 |..!...n.........|
00000230 23 22 07 00 6e 30 03 00 10 02 0e 00 02 00 00 00 |#"..n0..........|
| Name | Format | value |
|---|---|---|
| registers_size | ushort | 0x05 |
| ins_size | ushort | 0x02 |
| outs_size | ushort | 0x03 |
| tries_size | ushort | 0x00 |
| debug_info_off | uint | 0x372 |
| insns_size | uint | 0x26 |
| insns | ushort[insns_size] | 0x1f0开始的38个双字节 |
| padding | ushort (optional) = 0 | tries_size == 0 或者 insns_size 不是奇数(odd)，所以这项为空 |
| tries | try_item[tries_size] (optional) | 空 |
| handlers | encoded_catch_handler_list (optional) | 空 |
为了简单起见，只解析direct_method[1]的code_item。
指令内容：1a 00 15 00 1a 01 04 00 71 20 02 00 10 00 0e 00
步骤
- 查看Dalvik instructions中的 Summary of bytecode set，确定指令格式，占几位，使用的寄存器个数等等，分离出一个完整的指令；注意，每一个16bit编码单元都是小端序，所以op有第一个字节指定，数据由后续字节指定；
- 根据寄存器内容获得确定的值或者常量；
- 写出可供阅读的指令语法Syntax。
分析过程
- 查表
由于第一个字节是1a，所以查到以下表项：
| 1a 21c | const-string vAA, string@BBBB |A:destination register (8 bits)B:string index | Move a reference to the string specified by the given index into the specified register. |
1a 21c：指令占两个16bit，一个寄存器和一个常量池索引。
完整指令：1a 00 15 00 - 确定指令内容
1a： const-string vAA, string@BBBB
00： v0
15 00: 常量池中的索引是0x0015，第21个字符串，stringId =48 03 00 00=05 6d 79 4c 6f 67 00= ‘myLog’
string@： 字符串常量池 - 确定语句
const-string v0, ‘myLog’
所以：1a 00 15 00=const-string v0, 'myLog'
同理：
1a 01 04 00 = const-string v1, 'Hello World!'
71 20 02 00 10 00这一条复杂些，记录一下。
从71查表得71 35c，从id 35c查表得：
| A|G|op BBBB F|E|D|C | 35c | [A=5] op {vC, vD, vE, vF, vG}, type@BBBB [A=4] op {vC, vD, vE, vF},kind@BBBB [A=3] op {vC, vD, vE}, kind@BBBB [A=2] op {vC, vD}, kind@BBBB [A=1] op {vC}, kind@BBBB [A=0] op {}, kind@BBBB The unusual choice in lettering here reflects a desire to make the count and the reference index have the same label as in format 3rc. |
[A=2] op {vC, vD}, kind@BBBB
由0x7120，转换成小端序0x2071得：
A = 2
G = 0
op = 71，查表得invoke-static {vC, vD, vE, vF, vG}, meth@BBBB
由0x0200，转换成小端序0x0002得：
BBBB = 0002
由0x1000，转换成小端序0x0010得：
vC = 0
vD = 1
所以： 71 20 02 00 10 00 = invoke-static {v0,v1}, meth@0002
又：meth@0002 = 00 00 04 00 15 00 00 00
00 00:classid ==> ‘LDemo’;
04 00:protoid ==> 10 00 00 00 06 00 00 00 4c 02 00 00 ==> VLL V 02 00 00 ==> VLL V 2 x 0x02c1 ==> VLL V Ljava/lang/String; Ljava/lang/String;
15 00 00 00:stringid ==> ‘myLog’
得到完整的函数：LDemo;->myLog(Ljava/lang/String;Ljava/lang/String;)V
所以： 71 20 02 00 10 00 = invoke-static {v0,v1}, LDemo;->myLog(Ljava/lang/String;Ljava/lang/String;)V
第三条指令0e 00：
根据0e查表得到 0e 10x return-void Return from a void method.
根据10x查表得到ØØ|op 10x op，可知，0e 00的00表示ØØ，表示没有使用。
所以0e 00 = return-void
最后整理main函数：
.method public static main()V
const-string v0, "myLog"
const-string v1, "Hello World!"
invoke-static {v0,v1}, LDemo;->myLog(Ljava/lang/String;Ljava/lang/String;)V
return-void
.end method
附上baksmali.jar程序对classes.dex的分析
|
|-----------------------------
|header_item section
|-----------------------------
|
|[0] header_item
000000: 6465 780a 3033 3500| magic: dex\n035\u0000
000008: a783 a6ef | checksum
00000c: 3277 c2ea 3a2c 2363| signature
000014: 31b4 16b3 6eba 6e64|
00001c: f74e dd31 |
000020: 3004 0000 | file_size: 1072
000024: 7000 0000 | header_size: 112
000028: 7856 3412 | endian_tag: 0x12345678 (Little Endian)
00002c: 0000 0000 | link_size: 0
000030: 0000 0000 | link_offset: 0x0
000034: 9003 0000 | map_off: 0x390
000038: 1900 0000 | string_ids_size: 25
00003c: 7000 0000 | string_ids_off: 0x70
000040: 0900 0000 | type_ids_size: 9
000044: d400 0000 | type_ids_off: 0xd4
000048: 0600 0000 | proto_ids_size: 6
00004c: f800 0000 | proto_ids_off: 0xf8
000050: 0100 0000 | field_ids_size: 1
000054: 4001 0000 | field_ids_off: 0x140
000058: 0800 0000 | method_ids_size: 8
00005c: 4801 0000 | method_ids_off: 0x148
000060: 0100 0000 | class_defs_size: 1
000064: 8801 0000 | class_defs_off: 0x188
000068: 8802 0000 | data_size: 648
00006c: a801 0000 | data_off: 0x1a8
|
|-----------------------------
|string_id_item section
|-----------------------------
|
|[0] string_id_item
000070: 5a02 0000 | string_data_item[0x25a]: "\n"
|[1] string_id_item
000074: 5d02 0000 | string_data_item[0x25d]: ": "
|[2] string_id_item
000078: 6102 0000 | string_data_item[0x261]: "<init>"
|[3] string_id_item
00007c: 6902 0000 | string_data_item[0x269]: "Demo.java"
|[4] string_id_item
000080: 7402 0000 | string_data_item[0x274]: "Hello World!"
|[5] string_id_item
000084: 8202 0000 | string_data_item[0x282]: "L"
|[6] string_id_item
000088: 8502 0000 | string_data_item[0x285]: "LDemo;"
|[7] string_id_item
00008c: 8d02 0000 | string_data_item[0x28d]: "LL"
|[8] string_id_item
000090: 9102 0000 | string_data_item[0x291]: "LLL"
|[9] string_id_item
000094: 9602 0000 | string_data_item[0x296]: "Ljava/io/PrintStream;"
|[10] string_id_item
000098: ad02 0000 | string_data_item[0x2ad]: "Ljava/lang/Object;"
|[11] string_id_item
00009c: c102 0000 | string_data_item[0x2c1]: "Ljava/lang/String;"
|[12] string_id_item
0000a0: d502 0000 | string_data_item[0x2d5]: "Ljava/lang/StringBuilder;"
|[13] string_id_item
0000a4: f002 0000 | string_data_item[0x2f0]: "Ljava/lang/System;"
|[14] string_id_item
0000a8: 0403 0000 | string_data_item[0x304]: "V"
|[15] string_id_item
0000ac: 0703 0000 | string_data_item[0x307]: "VL"
|[16] string_id_item
0000b0: 0b03 0000 | string_data_item[0x30b]: "VLL"
|[17] string_id_item
0000b4: 1003 0000 | string_data_item[0x310]: "[Ljava/lang/Object;"
|[18] string_id_item
0000b8: 2503 0000 | string_data_item[0x325]: "[Ljava/lang/String;"
|[19] string_id_item
0000bc: 3a03 0000 | string_data_item[0x33a]: "append"
|[20] string_id_item
0000c0: 4203 0000 | string_data_item[0x342]: "main"
|[21] string_id_item
0000c4: 4803 0000 | string_data_item[0x348]: "myLog"
|[22] string_id_item
0000c8: 4f03 0000 | string_data_item[0x34f]: "out"
|[23] string_id_item
0000cc: 5403 0000 | string_data_item[0x354]: "printf"
|[24] string_id_item
0000d0: 5c03 0000 | string_data_item[0x35c]: "toString"
|
|-----------------------------
|type_id_item section
|-----------------------------
|
|[0] type_id_item
0000d4: 0600 0000 | string_id_item[6]: LDemo;
|[1] type_id_item
0000d8: 0900 0000 | string_id_item[9]: Ljava/io/PrintStream;
|[2] type_id_item
0000dc: 0a00 0000 | string_id_item[10]: Ljava/lang/Object;
|[3] type_id_item
0000e0: 0b00 0000 | string_id_item[11]: Ljava/lang/String;
|[4] type_id_item
0000e4: 0c00 0000 | string_id_item[12]: Ljava/lang/StringBuilder;
|[5] type_id_item
0000e8: 0d00 0000 | string_id_item[13]: Ljava/lang/System;
|[6] type_id_item
0000ec: 0e00 0000 | string_id_item[14]: V
|[7] type_id_item
0000f0: 1100 0000 | string_id_item[17]: [Ljava/lang/Object;
|[8] type_id_item
0000f4: 1200 0000 | string_id_item[18]: [Ljava/lang/String;
|
|-----------------------------
|proto_id_item section
|-----------------------------
|
|[0] proto_id_item
0000f8: 0800 0000 | shorty_idx = string_id_item[8]: LLL
0000fc: 0100 0000 | return_type_idx = type_id_item[1]: Ljava/io/PrintStream;
000100: 3c02 0000 | parameters_off = type_list_item[0x23c]: Ljava/lang/String;[Ljava/lang/Object;
|[1] proto_id_item
000104: 0500 0000 | shorty_idx = string_id_item[5]: L
000108: 0300 0000 | return_type_idx = type_id_item[3]: Ljava/lang/String;
00010c: 0000 0000 | parameters_off = type_list_item[NO_OFFSET]
|[2] proto_id_item
000110: 0700 0000 | shorty_idx = string_id_item[7]: LL
000114: 0400 0000 | return_type_idx = type_id_item[4]: Ljava/lang/StringBuilder;
000118: 4402 0000 | parameters_off = type_list_item[0x244]: Ljava/lang/String;
|[3] proto_id_item
00011c: 0e00 0000 | shorty_idx = string_id_item[14]: V
000120: 0600 0000 | return_type_idx = type_id_item[6]: V
000124: 0000 0000 | parameters_off = type_list_item[NO_OFFSET]
|[4] proto_id_item
000128: 1000 0000 | shorty_idx = string_id_item[16]: VLL
00012c: 0600 0000 | return_type_idx = type_id_item[6]: V
000130: 4c02 0000 | parameters_off = type_list_item[0x24c]: Ljava/lang/String;Ljava/lang/String;
|[5] proto_id_item
000134: 0f00 0000 | shorty_idx = string_id_item[15]: VL
000138: 0600 0000 | return_type_idx = type_id_item[6]: V
00013c: 5402 0000 | parameters_off = type_list_item[0x254]: [Ljava/lang/String;
|
|-----------------------------
|field_id_item section
|-----------------------------
|
|[0] field_id_item
000140: 0500 | class_idx = type_id_item[5]: Ljava/lang/System;
000142: 0100 | return_type_idx = type_id_item[1]: Ljava/io/PrintStream;
000144: 1600 0000 | name_idx = string_id_item[22]: out
|
|-----------------------------
|method_id_item section
|-----------------------------
|
|[0] method_id_item
000148: 0000 | class_idx = type_id_item[0]: LDemo;
00014a: 0300 | proto_idx = proto_id_item[3]: ()V
00014c: 0200 0000 | name_idx = string_id_item[2]: <init>
|[1] method_id_item
000150: 0000 | class_idx = type_id_item[0]: LDemo;
000152: 0500 | proto_idx = proto_id_item[5]: ([Ljava/lang/String;)V
000154: 1400 0000 | name_idx = string_id_item[20]: main
|[2] method_id_item
000158: 0000 | class_idx = type_id_item[0]: LDemo;
00015a: 0400 | proto_idx = proto_id_item[4]: (Ljava/lang/String;Ljava/lang/String;)V
00015c: 1500 0000 | name_idx = string_id_item[21]: myLog
|[3] method_id_item
000160: 0100 | class_idx = type_id_item[1]: Ljava/io/PrintStream;
000162: 0000 | proto_idx = proto_id_item[0]: (Ljava/lang/String;[Ljava/lang/Object;)Ljava/io/PrintStream;
000164: 1700 0000 | name_idx = string_id_item[23]: printf
|[4] method_id_item
000168: 0200 | class_idx = type_id_item[2]: Ljava/lang/Object;
00016a: 0300 | proto_idx = proto_id_item[3]: ()V
00016c: 0200 0000 | name_idx = string_id_item[2]: <init>
|[5] method_id_item
000170: 0400 | class_idx = type_id_item[4]: Ljava/lang/StringBuilder;
000172: 0300 | proto_idx = proto_id_item[3]: ()V
000174: 0200 0000 | name_idx = string_id_item[2]: <init>
|[6] method_id_item
000178: 0400 | class_idx = type_id_item[4]: Ljava/lang/StringBuilder;
00017a: 0200 | proto_idx = proto_id_item[2]: (Ljava/lang/String;)Ljava/lang/StringBuilder;
00017c: 1300 0000 | name_idx = string_id_item[19]: append
|[7] method_id_item
000180: 0400 | class_idx = type_id_item[4]: Ljava/lang/StringBuilder;
000182: 0100 | proto_idx = proto_id_item[1]: ()Ljava/lang/String;
000184: 1800 0000 | name_idx = string_id_item[24]: toString
|
|-----------------------------
|class_def_item section
|-----------------------------
|
|[0] class_def_item
000188: 0000 0000 | class_idx = type_id_item[0]: LDemo;
00018c: 0100 0000 | access_flags = 0x1: public
000190: 0200 0000 | superclass_idx = type_id_item[2]: Ljava/lang/Object;
000194: 0000 0000 | interfaces_off = type_list_item[NO_OFFSET]
000198: 0300 0000 | source_file_idx = string_id_item[3]: Demo.java
00019c: 0000 0000 | annotations_off = annotations_directory_item[NO_OFFSET]
0001a0: 7c03 0000 | class_data_off = class_data_item[0x37c]
0001a4: 0000 0000 | static_values_off = encoded_array_item[NO_OFFSET]
|
|-----------------------------
|code_item section
|-----------------------------
|
|[0] code_item: LDemo;-><init>()V
0001a8: 0100 | registers_size = 1
0001aa: 0100 | ins_size = 1
0001ac: 0100 | outs_size = 1
0001ae: 0000 | tries_size = 0
0001b0: 6603 0000 | debug_info_off = 0x366
0001b4: 0400 0000 | insns_size = 0x4
| instructions:
0001b8: 7010 0400 0000 | invoke-direct {v0}, Ljava/lang/Object;-><init>()V
0001be: 0e00 | return-void
|[1] code_item: LDemo;->main([Ljava/lang/String;)V
0001c0: 0300 | registers_size = 3
0001c2: 0100 | ins_size = 1
0001c4: 0200 | outs_size = 2
0001c6: 0000 | tries_size = 0
0001c8: 6b03 0000 | debug_info_off = 0x36b
0001cc: 0800 0000 | insns_size = 0x8
| instructions:
0001d0: 1a00 1500 | const-string v0, "myLog"
0001d4: 1a01 0400 | const-string v1, "Hello World!"
0001d8: 7120 0200 1000 | invoke-static {v0, v1}, LDemo;->myLog(Ljava/lang/String;Ljava/lang/String;)V
0001de: 0e00 | return-void
|[2] code_item: LDemo;->myLog(Ljava/lang/String;Ljava/lang/String;)V
0001e0: 0500 | registers_size = 5
0001e2: 0200 | ins_size = 2
0001e4: 0300 | outs_size = 3
0001e6: 0000 | tries_size = 0
0001e8: 7203 0000 | debug_info_off = 0x372
0001ec: 2600 0000 | insns_size = 0x26
| instructions:
0001f0: 6200 0000 | sget-object v0, Ljava/lang/System;->out:Ljava/io/PrintStream;
0001f4: 2201 0400 | new-instance v1, Ljava/lang/StringBuilder;
0001f8: 7010 0500 0100 | invoke-direct {v1}, Ljava/lang/StringBuilder;-><init>()V
0001fe: 6e20 0600 3100 | invoke-virtual {v1, v3}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;
000204: 0c01 | move-result-object v1
000206: 1a02 0100 | const-string v2, ": "
00020a: 6e20 0600 2100 | invoke-virtual {v1, v2}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;
000210: 0c01 | move-result-object v1
000212: 6e20 0600 4100 | invoke-virtual {v1, v4}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;
000218: 0c01 | move-result-object v1
00021a: 1a02 0000 | const-string v2, "\n"
00021e: 6e20 0600 2100 | invoke-virtual {v1, v2}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;
000224: 0c01 | move-result-object v1
000226: 6e10 0700 0100 | invoke-virtual {v1}, Ljava/lang/StringBuilder;->toString()Ljava/lang/String;
00022c: 0c01 | move-result-object v1
00022e: 1202 | const/4 v2, 0
000230: 2322 0700 | new-array v2, v2, [Ljava/lang/Object;
000234: 6e30 0300 1002 | invoke-virtual {v0, v1, v2}, Ljava/io/PrintStream;->printf(Ljava/lang/String;[Ljava/lang/Object;)Ljava/io/Print
|Stream;
00023a: 0e00 | return-void
|
|-----------------------------
|type_list section
|-----------------------------
|
|[0] type_list
00023c: 0200 0000 | size: 2
000240: 0300 | type_id_item[3]: Ljava/lang/String;
000242: 0700 | type_id_item[7]: [Ljava/lang/Object;
|[1] type_list
000244: 0100 0000 | size: 1
000248: 0300 | type_id_item[3]: Ljava/lang/String;
00024a: 0000 |
|[2] type_list
00024c: 0200 0000 | size: 2
000250: 0300 | type_id_item[3]: Ljava/lang/String;
000252: 0300 | type_id_item[3]: Ljava/lang/String;
|[3] type_list
000254: 0100 0000 | size: 1
000258: 0800 | type_id_item[8]: [Ljava/lang/String;
|
|-----------------------------
|string_data_item section
|-----------------------------
|
|[0] string_data_item
00025a: 01 | utf16_size = 1
00025b: 0a00 | data = "\n"
|[1] string_data_item
00025d: 02 | utf16_size = 2
00025e: 3a20 00 | data = ": "
参考文献
hex To str在线工具
html To markdown
Android dex format official site