Gentoo Archives: gentoo-java

From: dalibor topic <robilad@×××××.org>
To: Rene Bartsch <ML@××××××××××.de>
Cc: gentoo-java@l.g.o
Subject: Re: [gentoo-java] GCJ with IcedTea classpath?
Date: Thu, 17 Jul 2008 10:54:47
Message-Id: 487F24DB.2040907@kaffe.org
In Reply to: [gentoo-java] GCJ with IcedTea classpath? by Rene Bartsch
1 Rene Bartsch wrote:
2 > Hi,
3 >
4 > if I'm understanding correctly, GCJ >= 4.3 is a fully compatible Java-VM
5 > and Java-Compiler.
6 Not quite - GCJ makes no claims of full compatibility with any specific
7 Java release.
8 > But the drawback is the incomplete GNU.org classpath.
9 > On the other hand the OpenJDK classpath is incomplete due to proprietary
10 > code, too.
11 >
12 Not any more - the remainder of the OpenJDK class library has been freed
13 over the past
14 year. There is a tiny slice of SNMP code left over, but that's not part
15 of the platform specification,
16 so it's not necessary for a fully compatible implementation.
17 > Because of that Redhat added packages of the GNU.org classpath to OpenJDK
18 > and called it IcedTea.
19 >
20 That was the world as it was a year ago, yeah. IcedTea has moved on to
21 serve other duties meanwhile
22 (for example as integration point for Zero, gcjwebplugin/netx, etc.),
23 since OpenJDK over the past year
24 completed the work on the proprietary encumbrancies (in collaboration
25 with IcedTea, of course).
26 > So the question came to my mind whether it is possible to get a fully
27 > compatible JVM and native code compiler by combining GCJ with the IcedTea
28 > classpath?
29 >
30 Could be - but it would not be trivial work. For a start, you'd really
31 want to decouple gcj from the existing classpath
32 class library, which it currently has to patch, and drag a copy around
33 of. That's something that took
34 quite a while to accomplish for Kaffe, for example, as it is by no means
35 a trivial task to do it right.
36
37 Then you'd want to introduce a shim layer for using an installed openjdk
38 as its class library, and implement the
39 necessary low level interfaces in gcj.
40
41 Once you're done with that, you'd get in touch with me for a TCK license
42 for OpenJDK, and spend a fair bit
43 of time working on fixing the issues exposed by the test suite making
44 sure that you have a fully compatible combination.
45
46 cheers,
47 dalibor topic
48
49 > Thanx for any hint ...
50 >
51 >
52 > Renne
53 >
54 >
55
56 --
57 gentoo-java@l.g.o mailing list