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Latest version of the Debian/JAVA FAQ

	I'm attaching the latest revision I've had time to make to the
Debian/JAVA faq.. I appreciate new contributions, of course, but I think it
might be ready to include in java-common. Opinions? If no one disagress I
will file a wishlist bug against java-common and doc-debian, one to include
the FAQ and another one so that Josip points in the Debian FAQ to the
Debian/JAva FAQ.


PD: If someones volunteers to maitain this FAQ I would appreciate it deeply.
I'm not currently subscribed to the debian-java mailing list, also I do not
have much time to keep the FAQ up to date with news...
                             Debian Java FAQ.

             Javier Fernández-Sanguino Peña <jfs@computer.org>

                               19 marzo 2000



     Answers to Frequently Asked Questions on Debian and Java. Any changes
     to this FAQ are appreciated, please send them to the current

Nota de Copyright

     Copyright © 1998,1999 Javier Fernández-Sanguino Peña, The current FAQ
     has been made with tidbits of information from the debian-java mailing
     list and made available freely to all interested.



     1.        Introduction
     1.1.      What is java?
     1.2.      Why would I be interested in Java?
     1.3.      What is a JIT?
     1.4.      Where can I read more about Java?
     1.5.      Status of Java in Debian

     2.        Java development
     2.1.      What java development platforms are available in Debian?
     2.2.      What free platforms are there and how can I contribute?
     2.3.      Questions on commercial platforms

     3.        Java Compilers
     3.1.      What Java compilers are available in Debian?

     4.        Java Virtual Machines (JVM)
     4.1.      What jvms work in Debian?
     4.2.      What free JVMs are available in Debian?
     4.3.      Are there known problems?

     5.        Java-related programs
     5.1.      What java related programs are available in Debian?
     5.2.      Making packages for Java progams.
     5.3.      Installer packages

     6.        Java servlets
     6.1.      How can I make Java servlets work?
     6.2.      Do servlets work with kaffe?
     6.3.      Do I need commercial Java in order to run servlets?

     7.        Java policy
     7.1.      Is there a Java policy for Debian?
     7.2.      Are there Holes in the Java Policy?

     8.        Running Java in Debian
     8.1.      Is there a way, using free software, to run a Java program
               in Debian?
     8.2.      Other Java programs not yet available on Debian


1. Introduction

1.1. What is java?

     Java is a strongly-typed platform-independant object-oriented
     programming language often associated with the World Wide Web. Java
     was developed by Sun Microsystems for embedded applications, but has
     since grown to become a general-purpose programming language. Java
     source code can either be compiled to a machine-independant byte-code
     that can be run by java virtual machines, or it can be compiled
     directly to executable code for any number of platforms, including
     Linux, Win32, and others. A common API, shipped with all commercial
     java development environments, provides socket support, a graphical
     user interface widget set, graphical drawing tools, standard IO,
     events, math, database interfaces, and multithreading, to name a few.
     The multithreading support can happen either in kernel threads or user
     threads, depending on the implementation of the java virtual machine

1.2. Why would I be interested in Java?


1.3. What is a JIT? 

     Acronym for Just In Time, A VM plugin to speed up VM execution by
     compiling bytecode to native machine code.

1.4. Where can I read more about Java?
     Of course, http://java.sun.com would be the first place to read
     information on Java, right from the company who started it. However
     good places for Java and Linux could be: 

        * Enterprise Java for Linux HOWTO Gary Meyer
          -for-Linux-HOWTO.html. Explains how to set up an environment
          including JDK, web server, Java servlets, JDBC access to a
          database and EJBs. If you are interested read also Java
          Enterprise in a Nutshell at
        * The Linux Journal Magazine, the following articles might be worth

             * Issue 66 Java servlets
               and Java 2 SDK

             * Issue 45

             * Issue 33 http://www.linuxdoc.org/LDP/LG/issue33/burtch.html

             * Issue 32

             * Issue 25

        * Linux users worlwide includes information on how to use Java an
          Linux http://linuxusers.webprovider.com.

        * Linux Java Tips and Hints at http://www.parnasse.com/java.shtml.

        * The Java and Linux Page

        * The Java-CGI HOWTO from David H. Silber.
          http://www.linuxdoc.org/HOWTO/Java-CGI-HOWTO.html. Explains how
          to set up your server to run Java CGIs. Maybe it is worth looking
          at servlets.

     Other sites regarding Java would be: 

        * The Java Lobby http://www.javalobby.org.

        * Brewing Java: a tutorial at

     If you are browsing the web for free Java information try starting
     with Open-Source Java (http://members.tripod.com/~mpTOOLS/ring.html) ,
     if you are looking for applets with source code look at
     http://javaboutique.internet.com/javasource.html. Check also section
     2.2, `What free platforms are there and how can I contribute?'

1.5. Status of Java in Debian

     The first thing you should understand about the design strategy of
     Debian is that our goal is to produce a 100% Free software platform.
     In that sense, some of these tools are not available in the standard
     Debian distribution for licensing reasons as opposed to some technical

     That said, basically all of the technologies you might ask about can
     be or are available for Debian immediately. In order to usefully
     answer your questions, however, here you have a status from an Open
     Source availability perspective.

     If you are _really_ interested, read the threadas following
     This section is a summary of the information therein.

1.5.1. Java1 compiler (.java to .class)

     There is the Kopi Java Compiler written in Java. And the super fast
     Jikes written in C++.

     Gcj can also compile .java to .class. It currently does not handle
     inner classes, but that is being actively worked on. It is written in
     C, so is reasonably fast. It generates reasonable good bytecode. And
     of course being able to use the same compiler for .java to .class and
     .java to native has its advantages.

1.5.2. Java1 JVM/JIT

     Kaffe 1.0.5 is largely feature complete and now includes support for
     RMI. It is not clear as to whether Kaffe's serialization is "pin
     compatible" with Sun's implementation in all cases so there may be
     interoperation issues in some casses. Kaffe comes with a big class

     Japhar is also available.

     libgcj (the run-time library for gcj) now includes an interpreter and

     tya, a JIT compiler is also available.

1.5.3. Java1 native compiler

     GCC, the Gnu Compiler Collection comes with GCJ, the Gnu Compiler for

1.5.4. Java2 native compiler

     It is unclear whether native compiler refers to the adaptive JIT
     capabilities in Java2 or to a compiler that understands Java2
     semantics. In either case, Kaffe's JIT strategy is not adaptive but is
     still performant and becoming more so and it is believed IBM's Jikes
     compiler understands Java2 concepts such as weak references.

1.5.5. Java2 foundation libraries

     Many of these components have been cloned under a Free Software
     license. Kaffe provides many of these routines, including an
     up-to-date RMI implementation. There are, however, definatly
     shortcomings. Swing, as far as I know, has not been cloned.

1.5.6. Debugger (jdb equivalent)

     Debian has no debugger currently.

     Gdb can debug code produced by Gcj. Stuart Grossman (Cygnus) also
     wrote support for Gdb to debug other VMs using JVMDI. This has not
     been released, because the Gdb internals were changed at the same
     time, and no-one has had time to re-integrate the changes. We can
     probably get Cygnus to release the old code, if someone wants to look
     into getting this stuff working with the current Gdb internals. (A
     non-trivial job.)

     See http://sourceware.cygnus.com/java/gdb.html on how to debug
     gcj-compiled Java programs. What free edit-interactive/graphical debugging tools are available
on Debian?

     jde, ddd, more? Known problems

     My version of `jdb' (jdb version 98/01/06) terminates after a program
     finishes execution, and I have to reset every breakpoint if I want to
     run through the program again. This makes using jdb extremely
     frustrating. Jdb also can't (easily) print the values in an array
     which is more than three elements long. Ddd lets me work around both
     of these annoyances.

     `ddd' 3.1 and earlier would "hang" when receiving certain prompts with
     wierd thread names from jdb. This made it very hard to use ddd with
     jdb. This has been fixed in ddd 3.2. It doesn't look like ddd 3.2 has
     been packaged yet. I suspect the current packaged version of ddd won't
     work well with jdb.

1.5.7. Appletviewer tool
     There are some alternatives for an appletviewer tool: 

        * Blackdown's appletviewer (in jdk1.1).

        * Kaffe's appletviewer.

        * Ibm's appletviewer (in ibm-jdk).

1.5.8. Jar tool

     `FastJar' which is indeed very fast.

1.5.9. Javadoc tool

     `doc++' can work with C++ and Java.

1.5.10. Enterprise Java Beans (EJB)

     There is activity in this area, the most noteworthy being the Open
     Source EJB implementation from Bull in France called Jonas. I have
     done some work with this system and it provides a good start towards a
     full EJB feature set. In particular, it provides a transaction monitor
     and a container based persistance implementation. I have used this
     system on Linux with free databases such as Postgresql. I have not
     been able to get the system fully operational on Kaffe. Additionally,
     the system depends on many Sun APIs which have not been cloned (JTA,
     JNDI, and EJB itself).

1.5.11. JAIN

     It seems to be a system for controlling large scale, integrated
     communications infrastructures and modeling events with such networks
     via the JavaBeans API. The scale of this effort seems very large and
     encompasses the work of many organizations. The work is very new and
     seems to tie into Sun's SCSL strategy, which leads us me to believe
     that there is not much in the way of Open Source options in this area.
     However, some protocols such as H.323 are genuinely open and are even
     cloned so it is possible that chunks of the JAIN system may exist in a
     scattered manner. We have no knowledge of a serious Free Software
     implementation of RTP or the H.323 infrastructures in Java.

1.5.12. Jini

     Jini presents an especially pronounced Free Software problem. Jini is
     only available as source from Sun and that source is only available
     under the SCSL. The SCSL is not compatible in any sense with either
     the legal mechanics or the political spirit of Free Software. The SCSL
     also makes cloning the API of an SCSL implementation illegal which
     precludes even a clean room replication of Jini. If you are interested
     in tuple space type implementations there are Open Source options.


2. Java development

2.1. What java development platforms are available in Debian?

        * Sun's jdk 1.1 (port made by Blackdown www.blackdown.org)

        * `kaffe'.

        * ibm's jdk (see subsection 5.3.1, `What Java programs have an

2.2. What free platforms are there and how can I contribute?
     Please help one of the Free Java implementations if you want to use
     Java in Debian. There are a lot of projects that you can choose from: 

        * kaffe: http://www.kaffe.org or http://www.transvirtual.com.

        * Japhar: http://www.japhar.org. The Java virtual machine of
          "Hungry Programmer". More info in

        * gcj and libgcj: http://sourceware.cygnus.com/java/

        * jikes: http://www.research.ibm.com/jikes/. A fast compiler
          written in C++ (check also
          (The new license seems to be finally really free)

        * kopi: http://www.dms.at/kjc/.Yet Another Free Java Compiler, this
          time written in Java, and GPL. Included in Kaffe since release

        * FastJar http://fastjar.sourceforge.net/, as a jar tool. (this
          link seems to be broken, anyone?)

        * Classpath http://www.gnu.org/software/classpath/ or
          http://www.classpath.org. Most of the Standard classes for Java
          1.2 (except Swing and RMI) are implemented by the ClassPath
          project, it tries to build an alternative to jdk's 1.2 core

        * Most of the RMI classes are implemented by NinjaRMI

        * Autoconf macros
          http://www.internatif.org/bortzmeyer/autoconf-Java/ helps easy
          recompilation of Java programs.

        * Mauve http://sourceware.cygnus.com/mauve/ is a free suite to test
          if these tools are 'compliant'.

     There is a list on free java at
     http://www.lists.deus.net/mailman/listinfo/free-java, also look
     http://www.gnu.org/software/java/ for information about Free Java.

2.3. Questions on commercial platforms 

2.3.1. JDK1.2
------------- Why is not Sun's jdk 1.2 available?

     Due to license problems. Clause 2 of the license that comes with is
Software is confidential and copyrighted. Title to Software and all
associated intellectual property rights is retained by Sun and/or its
licensors.  Except as specifically authorized in any Supplemental License
Terms, you may not make copies of Software, other than a single copy of
Software for archival purposes. What are the problems with Suns' new license?

     Sun has moved to a new license the _Sun Community License_, like the
     GPL it is a viral license, but making all it touches subject to Sun
     licensing fee. The SCSL even goes so far as to define any
     implementation of a Sun specification as a "Modified Work". Basically,
     this means that if you implement any part of the new 1.2 API or Jini
     API, even from scratch, Sun will "own" your implementation and you
     will have to pay them for the right to use it. 
          13.  "Modification(s)" means (i) any change to Covered Code;
               (ii) any new file or other representation of computer
               program statements that contains any portion of Covered
               Code; and/or (iii) any new Source Code implementing any
               portion of the Specifications. Can I use jdk1.2 while working with the free java implementations?

     Clause 1 of the Supplemental License Terms says: 
           [You] may not create, or authorize your licensees to create
           additional classes, interfaces, or subpackages that are contained in
           the "java" or "sun" packages or similar as specified by Sun in any
           class file naming convention;

     Which seems to prevent one from making his own implementation of the
     standard java classes using the JDK.

2.3.2. IBM's jdk1.1
------------------- Can Debian distribute IBM's jdk1.1?

     It seems not. It has the following license: 
Program Code

Consists of the IBM Developer Kit for Linux(R), Java(TM) Technology Edition,
Version 1.1.8, in Binary Code form, as modified by IBM to run on the RedHat(R)
6.0 Linux or Caldera(R) OpenLinux 2.2 Operating systems. The Program Code
consists of the Java virtual machine, the Java platform core classes and
supporting files (also known as the Java Runtime Environment or JRE) Java Tool
Kit, Documentation and Java Samples. Program Code may include soft copy
documentation, readme files, program data and such like.

You may only use the Program Code if you are a current licensee of Redhat 6.0
Linux or Caldera OpenLinux 2.2 Operating systems and the Program Code may only
be used in conjunction with such products.

     See bug #54641 for an issue about IBM JDK. You can dowload it from
     http://www.ibm.com/java/jdk/118/linux. Is it possible to obtain a licence for Debian 2.1?

     It would still be non-free, because of item 8 in the DFSG "License
     Must Not Be Specific to Debian".

2.3.3. JRE
---------- Can Debian distribute JRE?

     http://www.debian.org/Lists-Archives/debian-java-9908/msg00021.html) I
     don't think we can or want to distribute the JRE with Debian. The
     supplemental license terms of the JRE has a few very nasty clauses: 
 1. License to Distribute. You are granted a royalty-free right to
  reproduce and distribute the Software provided that you: (i)distribute
  the Software complete and unmodified, only as part of, and for the
  sole purpose of running, your Java applet or application ("Program")
  into which the Software is incorporated;

     We might get away with this one since we distribute it together with
     Java applications bundled with Debian. But we also do want to allow
     people to download only the jre package. 
            (ii) do not distribute additional software intended to replace any
            component(s) of the Software;

     But we cannot agree to this one. We want to distribute Kaffe, Japhar,
     Classpath, Gcj, Kopi, Fastjar, etc which are intended to replace the
     JRE with a Free version. Even if we don't consider non-free part of
     Debian (the JRE would not go into main :) I think we should not
     encourage software that tries to prevent Free replacements. 
  [...] (v) may not create, or authorize your licensees to create additional
  classes, interfaces, or subpackages that are contained in the "java" or
  "sun" packages or similar as specified by Sun in any class file naming

     My example why this is a bad clause was not so good since someone
     pointed out that you do not want to create something that is non
     standard. I do agree that we want a standard implementation of the
     core classes, but I also think that you should have the freedom to
     create non-standard classes. (Or fix bugs or stupid mistakes in the
     standard classes.) 
  [...] and(vii) agree to indemnify, hold harmless, and defend Sun and its
  licensors from and against any claims or lawsuits, including attorneys'
  fees, that arise or result from the use or distribution of the Program.

     And I don't think that Debian (or SPI) can or wants to do that.

     So I am afraid that we also cannot distribute the Sun or Blackdown
     JRE. This isn't that bad since it is non-free software, but it is
     annoying. As I said before please help one of the (many) Free Java
     projects out there if you want to see a Free JVM, Standard Classes,
     Compiler, etc. in Debian. They are far from complete but they do work
     for most purposes


3. Java Compilers

3.1. What Java compilers are available in Debian?

        * `guavac'. The compiler of Effective Edge Technologies. This
          compiler is orphaned upstream, for real work use gcj or yikes.

        * `tya'. A just in time compiler, used to compile java to byte

        * `yikes'.

        * `bock'. Java to C compiler.

        * `gcj'. Compiles Java source to native code.

        * `gck'. Is this available?

        * `kjc' is included in `kaffe' 1.0.5. There currently is no
          separate package.


4. Java Virtual Machines (JVM)

4.1. What jvms work in Debian? 

     Currently Sun's jdk and Ibm's jdk work in Debian. (But, for simple
     programs such as the ones used for teaching, the free kaffe VM may be
     enough. Another solution is to use gcj and to compile to native code,
     thus solving the VM problem.)

4.2. What free JVMs are available in Debian?

        * `kaffe'. Cannot run all programs, although it is alleged to run
          Jigsaw (a 10Mb distribution) see

4.3. Are there known problems?

        * Kaffe loops endlessly on the XML parsing.


5. Java-related programs

5.1. What java related programs are available in Debian?

5.1.1. Deban 2.1 'slink'

        * `vrwave'. A Java VRML browser.

        * `icq-java'. An installer for the ICQJava program.

        * `jde'. A Java Development Enviroment for Emacs

        * `jlex'. A lexical analyser generator similar to the UNIX `lex'.

        * `mmake'. A generator of Makefiles for java programs. More info at

        * `libpgjava'. A java class that enables communication with the
          PostgreSQL database using JDBC.

        * `cup'. A parser similar to `yacc'.

        * `ilu-javadev'. Development header and libraries for the
          Inter-Language Unification System. I've installed the latest jde package...what I have to do to let
Emacs enter jde-mode automatically when loading a Java source file?

     As explained in /usr/doc/jde/README.Debian, all that is required is
     putting `(require 'jde)' into your `~/.emacs' file.

     Note that other add-on packages to Emacs are not enabled by default
     either, e.g., AucTeX.

5.1.2. Debian 2.2 'potato'
        * Libraries 

             * lib-fop-java

             * lib-gnu.getopt-java

             * lib-gnu.regexp-java

             * lib-openxml-java

             * lib-rxtx-java

             * lib-sax-java

             * lib-xp-java

             * lib-xslp-java

             * lib-xt-java

             * lib-dom-java

             * libpgjava

             * libgcj0

        * `bock' Bootstrap-only compiler kit for a subset of Java(tm)

        * `doc++'. A documentation system for C/C++ and Java

        * `fastjar' a complete replacement for the jar utility written in C
          under the GPL http://www.engr.orst.edu/~burnsbr/fastjar/ (check

        * `java2html'. Highlits Java sources for WWW presentations.

        * `gcj' The GNU compiler for Java(TM).

        * `global'.Source code search and browse.

        * `guavac'. A java compiler.

        * `jikes'. Fast Java compiler adhering to language and VM

        * `jikes-pg'.Jikes Parser Generator.

        * `oo-browser'.Object Oriented (X)Emacs Class Browser.

        * `mmake'.Makefile generator for Java programs.

        * `cocoon'. A XML/XSL publishing framework servlet

        * `bsh' A Java scripting environment.

        * `cup'. LALR parser generator for Java.

        * `freetds-jdbc'. Pure Java JDBC driver for MS SQL and Sybase.

        * `gnujsp'. A free implementation of Sun's Java Server Pages (JSP

        * `jlex'.A Lex-style lexical analyser generator for Java

        * `jserv'Java Servlet 2.0 engine with an optional Apache module

        * `tya'.JIT-compiler for Java.

        * `ibm-jdk1.1-installer'. Installer for IBM Developer Kit for
          Linux, Java(TM) Technology Edition. (see subsection 5.3.1, `What
          Java programs have an installer?').

        * `jdk1.1'.JDK 1.1.x (Java Development Kit) - Runtime only

        * `jdk1.1-dev' JDK 1.1.x (Java Development Kit)

        * `biss-awt' a Java GUI application programming framework.

        * `jdk1.1-native'.JDK 1.1.x Runtime - native threads extensions

        * `jdk1.1-native-dev'. JDK 1.1.x - native threads extensions.

        * `vrwave'.VRML 2.0 java-based browser

     Also many editors (jed, elvis, vim, emacs, fte, xcoral,zed ....) have
     support for Java sintax.

5.1.3. Is there a a free javadoc implementation? 

     You might take a look at http://www.zib.de/Visual/software/doc++/, it
     is package for Debian, in packages `doc++' and `doc++-doc'

5.2. Making packages for Java progams.

5.2.1. Can the package go to main?

     Since there is not yet a free java environment in Debian, the
     dependance on any package to JDK avoids any Java program to be in
     `main' even if it uses a free license, the program should be moved to
     `contrib'. _But_ if you can sucessfully demonstrate that your program
     can compile and work with free tools it can be moved to `main'.

5.2.2. What virtual packages could I use?

        * `java-common'. It is the Mother Of All Java Packages, in the
          proposed policy. It contains the text of the Policy (Docbook), as
          well as utilities scripts (for instance to build a CLASSPATH from
          a list of jars (submissions welcome).

        * `java-virtual-machine'

        * `java-compiler'
        * `java-compiler-dummy'.It is a small tool useful for the
          transition to the new Policy. Until all compilers comply with the
          Policy, java-compiler-dummy provides the following services: 

             * Provides: java-compiler so upper packages are happy,

             * set CLASSPATH before calling the real compiler.

        * `java-virtual-machine-dummy'.It is a small tool useful for the
          transition to the new Policy. Until all virtual machines comply
          with the Policy, java-virtual-machine-dummy provides the
          following services: 

             * Provides: java-virtual-machine so upper packages are happy,

             * set CLASSPATH before calling the real VM.

5.3. Installer packages

5.3.1. What Java programs have an installer?

        * `vajava' is a visual IDE for Java. You can find it in
          http://software.ibm.com/ad/vajava._TODO: check copyright_. The
          installer can be found at

        * `ibm-jdk1.1'. Installer for IBM Developer Kit for Linux, Java(TM)
          Technology Edition. It will install an alpha version 1.1.6 of the
          IBM Developer Kit. The IBM Developer Kit is a development
          environment for writing applets and applications that conform to
          the Java 1.1 Core API. Its compiler and other tools are run from
          a shell and have no GUI interface.

          The IBM Developer Kit includes the IBM JIT (libjitc.so) which is
          used by all tools by default. Look for it in
          http://master.debian.org/~doko. Needs to be upgraded to 1.1.8.
          However it seems that providing an installer might break their
          license (see subsection 2.3.2, `IBM's jdk1.1')

        * `jdk1.2-installer'. Look for it in
          http://www.pobox.com/~julio/debian/jdk1.2-installer/. This one
          works for the pre-release version, a little work is needed in
          order to install the release candidate version.

5.3.2. What Java programs could I develop an installer to?

        * `jdk-1.2.2' SE Standard Edition

        * Blackdown's `jdk-1.2.2'

        * `jbuilder3'. A java IDE from Inprise (written in java)
          Works well.

        * `netbeans'. Another java IDE (also written in java)
          http://www.netbeans.com/ for writing bean based GUI apps.


6. Java servlets

6.1. How can I make Java servlets work?
     You can use: 

        * GNUJSP

        * Apache Jserv. http://java.apache.org/jserv/index.html.

     Also others not yet packaged for Debian but which migh be soon
     included are: 

        * tomcat from ://jakarta.apache.org/tomcat/.

        * jigsaw from http://www.w3.org/Jigsaw/.

        * Jetty http://mortbay.com/software/Jetty.html (tested successfully
          on a potato machine)

6.2. Do servlets work with kaffe?

     The `servlet.jar' in Kaffe will not work. It is only a shell. There is
     another LGPL implementation that was written by Paul and Mark
     Wielaard. It is available at http://www.euronet.nl/~pauls/java/servlet
     these will have (have been?) added Apache JServ package so the user
     doesn't have to download Sun's classes any longer.

6.3. Do I need commercial Java in order to run servlets?

     Not known. Possibly not, need to explain.


7. Java policy

7.1. Is there a Java policy for Debian?

     It is still in the works. The current policy addresses _some_ of the
     problems. It has not been officially released. You can find it in

7.2. Are there Holes in the Java Policy?

     Yes, some until under discussion.Thus it is _very_ inconvenient to use
     serveral compilers of virtual machines since there is not one
     CLASSPATH setting for all.


8. Running Java in Debian

8.1. Is there a way, using free software, to run a Java program in Debian?

     Yes there is, since the problem currently now is the jvm you can try
     to run applications without a jvm. How? Compiling to native code is
     the solution.

8.1.1. How do I compile to native code?

     You might not be able to use gcj since it fails on many Java
     constructs, so you cannot compile the program directly. But you can
     compile with `jikes' (which is a free program, also), and use `gcj' to
     convert bytecode to native code. The entire sofwtare chain is free.

8.1.2. Are there any successes using this approach?

     Most certainly, read in
     how this was done for the XML parser `xp'. 
ezili:~/infosystems/XML/Java> gcj --main=UnTag UnTag.java UnTagHandler.java
/usr/share/java/repository/org/xml/sax/*.class /usr/share/java/repository/com/j
clark/xml/sax/*.class /usr/share/java/repository/com/jclark/xml/parse/*.class

8.1.3. Are there any problems with this approach?

     Yes there are also some problems.

     `gcj' does not support JNI, and in previous inquiries to Cygnus, we
     did not get get the impression that JNI is a priority. IIRC Tom Tromey
     said that JNI could be implemented on top of CNI, and that outside
     contributors are welcome to add it.

     Lack of JNI affects use of Classpath (e.g. as an alternative to
     libgcj) as well as small, standalone apps that replace AWT with some
     really simple GUI (like using curses, e.g. for small installers). It
     also affects projects which have native code for performance reasons.
     At the moment, gcj basically forces a CNI port. The only alternative
     we are aware of is TowerJ, which is good for commercial projects, but
     does not offer anything to free software.

8.1.4. Does these work for architectures different than i386?

     Possibly not, since libgcj does not build on sparc and no one has
     tried this for arm.

8.2. Other Java programs not yet available on Debian
     The following are programs that have not yet been packaged for Debian
     nor is there an installer. There are quite some Java programs out
     there and this list is not an exhaustive list, it only includes
     programs that _might_ be packaged for Debian or those that someone is
     working an installer for: 

        * BlueJ. A development environment for Java with editor, compiler,
          virtual machine and debugger. See http://bluej.monash.edu.au/

        * Jacob (Java Commando Base): project maintainer and visualiser for
          Java in Emacs. See http://home.pages.de/~kclee/clemens/jacob.

        * Netbeans developer. Based on the Javabeans architecture. See

        * AnyJ. Graphic environment to develop applications, applets and
          servlets. More info in http://www.netcomputing.de.

        * Free Builder. A Java IDE written in Java and distributed under
          the GPL http://www.freebuilder.org.

        * CodeGuide. http://www.omnicore.com. Free license for
          non-commercial use (CHECK).



     Debian Java FAQ.

     Javier Fernández-Sanguino Peña <jfs@computer.org>

     19 marzo 2000

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