jad是一个C++编写的跨平台的Java反编译命令行工具，可使用jad命令反编译class文件，jad最新版本是发布于2006年的1.5.8g，距今，已有14年没更新了。
    反编译示例：jad TestHelloWorld.class
    7. JAD - 图1

    JAD参数如下：

    1. Jad accepts the following options:
    3. -a       - annotate the output with JVM bytecodes (default: off)
    4. -af      - same as -a, but output fully qualified names when annotating
    5. -clear   - clear all prefixes, including the default ones (can be abbreviated as -cl)
    6. -b       - output redundant braces (e.g., if(a) { b(); }, default: off)
    7. -d 
    8.  - directory for output files (will be created when necessary)
    9.   -dead    - try to decompile dead parts of code (if any) (default: off)
    10.   -disass  - disassemble method bytecodes (no JAVA source generated)
    11.   -f       - output fully qualified names for classes/fields/methods (default: off)
    12.   -ff      - output class fields before methods (default: after methods)
    13.   -i       - output default initializers for all non-final fields
    14.   -l  - split strings into pieces of maximum  chars (default: off)
    15.   -lnc     - annotate the output with line numbers (default: off)
    16.   -lradix - display long integers using the specified radix (8, 10 or 16)
    17.   -nl      - split strings on newline character (default: off)
    18.   -nocast  - don't generate auxiliary casts
    19.   -nocode  - don't generate the source code for methods
    20.   -noconv  - don't convert Java identifiers (default: convert)
    21.   -noctor  - suppress the empty constructors
    22.   -nodos   - do not check for class files written in DOS mode (CR before NL, default: check)
    23.   -nofd    - don't disambiguate fields with the same names by adding signatures to their names (default: do)
    24.   -noinner - turn off the support of inner classes (default: on)
    25.   -nolvt   - ignore Local Variable Table information
    26.   -nonlb   - don't output a newline before opening brace (default: do)
    27.   -o       - overwrite output files without confirmation (default: off)
    28.   -p       - send decompiled code to STDOUT (e.g., for piping)
    29.   -pi - pack imports into one line after  imports (default: 3)
    30.   -pv - pack fields with identical types into one line (default: off)
    31.   -pa - prefix for all packages in generated source files
    32.   -pc - prefix for classes with numerical names (default: _cls)
    33.   -pf - prefix for fields with numerical names (default: _fld)
    34.   -pe - prefix for unused exception names (default: _ex)
    35.   -pl - prefix for locals with numerical names (default: _lcl)
    36.   -pm - prefix for methods with numerical names (default: _mth)
    37.   -pp - prefix for method parms with numerical names (default: _prm)
    38.   -r       - restore package directory structrure
    39.   -radix - display integers using the specified radix (8, 10 or 16)
    40.   -s  - output file extension (by default '.jad')
    41.   -safe    - generate additional casts to disambiguate methods/fields (default: off)
    42.   -space   - output space between keyword (if/for/while/etc) and expression (default: off)
    43.   -stat    - display the total number of processed classes/methods/fields
    44.   -t       - use tabs instead of spaces for indentation
    45.   -t  - use  spaces for indentation (default: 4)
    46.   -v       - display method names being decompiled
    47.   -8       - convert UNICODE strings into 8-bit strings
    48.   using the current ANSI code page (Win32 only)
    49.   -&       - redirect STDERR to STDOUT (Win32 only)

    官方网站：http://www.kpdus.com/jad.html#general
    版本下载：http://www.javadecompilers.com/jad