jode/jode

takes class-files as input and produces something similar to the
original java-File.  Of course this can't be perfect: There is no way
to produce the comments or the names of local variables (except when
compiled with <code>-g</code>) and there are often more ways to write
the same thing.  But it does its job quite well.</P>

<h2>Quick Test</h2>
I have now an applet interface to the decompiler.
<a href="jode-applet.html">Check it out</a>.

<h2>How to get it</h2>
<P>You can donwload the files in zip form. 
The <a href="jode_src.zip">sources</a> contain only the
<code>java</code> files, the <a href="jode_cls.zip">classes</a>
contain only the <code>class</code> files. </p>

<p>I also have a <a href="jode.tar.gz">tar.gz file</a> containing only
the <code>RCS</code> directories.  This is the form I maintain the
project, but you probably need unix and a few tools to use them.</p>

<p>There are also some <a href="snapshot/">snapshots</a> that have new
features like inner and anonymous classes. </p>

<p><a href=".">Click here</a> to browse the files online.
</p>



<h2>How to use it</h2>

<p>I have some simple step by step pages.  There are three
possibilities:
<ul>
<li> <a href="jode-useapplet.html"> Using the applet version</a>.
This can make problem due to java's security policy, but is the
simplest way and works on most platforms.
</li>
<li> If you use Windows, you should look on <a
href="jode-win.html">this page</a>.</li>
<li> Unix users should look on <a href="jode-unix.html">this page</a>.
</ul>

<h2>Known bugs</h2> 

<p>There may be situations, where the code doesn't understand complex
expressions. In this many ugly temporary variables are used, but the
code should still be compileable.  This does especially happen when
you compile with `-O' flag and javac has inlined some methods. </p>

<p>Sometimes this program may exit with an <code>Exception</code> or
produce incorrect code.  Most time the code can't be compiled, so that
it can be easily spotted.  If you have one of these problems (except
those that occur on some of the <code>jode.test</code> files, I would
be very interested in a bug report (including the <code>class</code>
file, if possible).</p>

<p>Sometimes it generates some <code>GOTO</code> expression and
labels.  This can't be compiled, but shouldn't happen any more with
javac or jikes.</p>

<p>It doesn't handle inner and anonymous classes, yet.  You can
decompile them separately, though (use `<code>+$</code>' switch under
jikes), but there is a bug in javac, so that a final variable is twice
initialized.  If you encounter this problem just remove the doubled
line by hand.  </p>

<p><b>New!</b> The latest <a href="snapshot">snapshot</a> can handle
inner and anonymous classes.</p>


<h2>Why did I wrote it?</h2> 

<p>Someday I found <code>guavad</code>, a disassembler for java byte
code (it does similar things like <code>javap&nbsp;-c</code>).  I used
it on a class file, and found that it was possible to reconstruct the
original java code.  First I did it by hand on some small routines,
but I soon realized that it was a rather stupid task, and that I could
write a <a href="../perl/dasm_to_java.perl"><code>perl</code> script</a>
that does the same.  At the end of the next day I had a working
decompiler.</p>

<p>Now while it was working, it was not easy to use.  You had to
decompile the code first with a disassembler, cut the method, you
wanted to decompile and then run the perl script on it.  So I decided
to get some information of the class files and do this all
automatically.  I decided to write it in <code>java</code> now,
because it suited best.</p>

<p>Just for the records: the java code is now more than 50 times
bigger than the original perl script and is still growing.</p>

<h2>License</h2> 

<p>This code is under GNU GPL.  That basically means, that you can copy
or modify this code, as long as you put all your modification under
the GPL again.  <A HREF="http://www.gnu.org/copyleft/gpl.html"> Look
here for the complete license</a>.</p>

<hr>

<p><A HREF="mailto:Jochen.Hoenicke@Informatik.Uni-Oldenburg.DE">
http://www.informatik.uni-oldenburg.de/~delwi/jode/jode.html</A>, last
updated on <em>17-Jun-1999</em>.</p>

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