1. Removal of dead methods and fields

2. Detection of live overridden methods

3. Removal of unused classes and interfaces

4. Inlining of methods

5. Removal of non-essential attributes

6. Shortening of internal method names and field names

7. Removal of non-used entries in the constant pool

After the above steps, JAX may use more aggressive compression techniques as well.

As a by product, a JAXed Java program is also obfuscated. Obfuscation makes the reconstruction of source code from byte codes difficult.

You should use JAX if you want to reduce the size of your Java program or if you want to obfuscate it.

The command line options that are supported are as follows:

java jax [command_line_options] <class_name> [selected_package]

where

<class_name>

starting class name

selected_package (optional)

the package of interest when loading the program

command_line_options (optional) are:

-nocompress

do not compress constant pools

-noobfuscate

do not shorten names of internal classes, methods, and fields

-notransform

do not merge classes

-noinline

do not inline method class

-simple

use simple analysis (not RTA) to determine essential artifacts

-noverify

do not partially verify the compressed application

-run

run the application after compressing

-runverbose

run the compressed application (verbosely)

-help

show help information

JAX generates two zip files, a log file, and a Windows batch file that facilitates running your compressed program on Windows NT or 95.

<class_name>_big.zip is the uncompressed program

<class_name>_jax.zip is the compressed program

<class_name>_jax.log is the log file

<class_name>_jax.bat is the Windows batch file

JAX looks for two optional input files in the current directory:

<class_name>_jax.dlc contains the names of all classes that are loaded dynamically

Example:

com.acme.ClassOne

com.acme.ClassTwo

com.acme.ClassThree

<class_name>_jax.fcn contains the names of all classes whose name cannot change. Don't add any names already specified in the *_jax.dlc file. Furthermore, there is no need for an *_jax.fcn file when you specify the -noobfuscate option.

Example:

com.acme.ClassFive

com.acme.ClassSiz

<class_name>_jax.dim contains the names of all the methods that are called using reflection

Example:

com.acme.ClassFour specialMethod1 (I)V

com.acme.ClassFour specialMethod2 (III)I

com.acme.ClassFour (Ljava/lang/Object;)V

Use the enclosed "methods" program to get a listing of available methods. Example:

java methods java.lang.String

Make sure that your CLASSPATH environment variable is correct. In particular, CLASSPATH must contains the path to jax33.zip. In addition, in some systems the CLASSPATH is case sensitive. In these systems please make sure the case sensitivity of CLASSPATH entries is maintained.