Introduction
The aim of “Java Decompiler” project is to develop tools to decompile and analyze Java 5, and upper, “.class” files.
Some facts:
* The final release of JSR 176, defining the major features of the J2SE 5.0, has been published the september 30, 2004.
* The lastest Java version supported by JAD, the famous Java decompiler written by Mr. Pavel Kouznetsov, is 1.3.
* Most of Java decompilers downloadable today from Internet, such as “DJ Java Decompiler” or “Cavaj Java Decompiler”, are powered by JAD : they can not display Java 5 sources.

Main features
* JD-Core and JD-GUI are written in C++. This allows an extremely fast decompilation and a display.
* JD-Core does not require the Java runtime environment for its functioning, therefore no special setup is required.
* JD-Core works with most current compilers including the following:
o jdk1.1.8
o jdk1.3.1
o jdk1.4.2
o jdk1.5.0
o jdk1.6.0
o jikes-1.22
o harmony-jdk-r533500
o Eclipse Java Compiler v_677_R32x, 3.2.1 release
o jrockit90_150_06
* JD-Core supports the following new features of Java 5:
o Annotations
o Generics
o Type “enum”
* JD-GUI supports Drag and Drop.
* JD-GUI supports JAR files.
* JD-GUI displays color coded Java source code.
* JD-GUI allows you to browse the “class” files hierarchy.
* JD-GUI displays “log” files, and allow you to decompile “class” files appearing in Java stack traces.
* JD-Core and JD-GUI use the excellent cross-platform wxWidgets toolkit.
Downloads
jd-gui-0.2.5.windows.zip
jd-gui-0.2.5.linux.i686.tar.gz
jd-gui-0.2.5.osx.i686.dmg

Red Hat Package Manager, abbreviated RPM, by default, you need install RPM under Red Hat, but some times, we just want to extract something from RPM without installation, how to?
I like using 7-Zip under Windows, it supports many formats:
* Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
* Unpacking only: RAR, CAB, ISO, ARJ, LZH, CHM, MSI, WIM, Z, CPIO, RPM, DEB and NSIS
so I think I can extract file from RPM with the help of 7-ZIP, but I am not sure if it has Linux version, so I googled it, it does not, but I found alternative, P7ZIP:

p7zip is a port of 7za.exe for POSIX systems like Unix (Linux, Solaris, OpenBSD, FreeBSD, Cygwin, AIX, …), MacOS X and BeOS.

now, I got it.
btw, under Debian or Ubuntu, it is very easy to install it and use,
apt-get install p7zip-full
7z x ABC.RPM
7z x ABC.cpio.gz
7z x ABC.cpio


Description
fcrackzip searches each zipfile given for encrypted files and tries to guess the password. All files must be encrypted with the same password, the more files you provide, the better.

Marc Lehmann releases an Open source zip password cracker, but it only have source and a very old windows version 0.3, so I compiled it under MSys and MingW, you can download the last version(fcrackzip-1.0-win32.zip) now.
for more info about fcrackzip, please visit FCrackZip manual
or Marc Lehmann’s “FCrackZip”

if you need it, please do not hesitate to download it now.
if you want linux version or source code, please download it here(fcrackzip-1.0.tar.gz).