Blackdown Java-Linux Java 2 SE v1.4.1-01 for ix86 and SPARC is available from ftp mirrors . Both the ix86 and the SPARC version include the HotSpot Client and Server VMs, as well as an enhanced version of Java Web Start 1.2 and a Java Plug-In for browsers based on Mozilla. The ix86 version also includes a Java Plug-In for Netscape 4.x browsers. Installation instructions for available for the SDK and the Runtime Environment.
Changes from v1.4.1-beta
– Improved graphics/imaging performance (up to 80% for some operations)
– Improved volatiles performance (especially in the Server VM)
– Fixed SSE2 memory barriers to get volatiles semantics correctly
– Support kernels with custom PAGE_OFFSETs (needed for some x86 kernels and the default kernel for x86-64)
– Fixed handling of stack overflows on the main thread for kernels with enabled heap-stack-gap (e.g. SuSE kernels)
– Complete LFS support
– Improved MappedByteBuffer implementation
– Support depth 24 display with 24 frame buffer bits per pixel
– Replaced some functions with thread safe equivalents
– Various small bug fixes
– Upgrade to Sun patch level 1.4.1_01
Java Web Start Notes
The bundled version of Java Web Start 1.2 can generate desktop icons and menu entries for both GNOME and KDE. The behavior can be customized on the ‘Shortcut Options’ tab in the preferences panel.”
I’d be grateful if someone could once and for all explain the differences, advantages and disadvantages of Blackdown’s, Sun’s own and IBM’s JDK.
I’m thinking in terms of 2 target areas: scientfic/numeric (CPU load, filesystem IO) applications and server (network, reliability, response) type applications.
i’ve tried google, usenet and the owners respsctive web site sto not much avail.
Does this mean I can have a JVM in Mozilla that was compiled with GCC 3? I wan’t my JVM back.
That would make a nice OSNEWS article
I am not really sure why would I use this version instead of Sun’s own? Yes, on Linux. I downloaded it today, it works as designed, with hotspot and stuff… and it has been out somewhat longer than Blackdown’s, so it’s rather better tested. And better documented, too. I would need some big fat reason to chose Blackdown’s Java.
From what I understand, here is the history:
From the beginning (around 1994) Sun had developed their own JDK for both Windows and Solaris. This is the Sun JDK everybody is used to knowing and loving/hating.
To bring Java to Linux, the Blackdown people (who I know nothing about) signed an NDA with Sun to get the proper technical support (particulary the testing suite that needs to be passed to make a JDK official) so that they could develop a JDK for Linux. I am NOT sure if they were allowed to use code from Sun’s JDK, but I would imagine they could. It is NOT open source, because Sun would never give tech support to an open source implementation for fear of losing control of Java. It was built to run on multiple architectures and (as far as I know) is still the only Linux JDK that will run on anything other than the x86 arch.
IBM licensed Java from Sun for it AIX Unix OS and eventually when they jumped on the Linux bandwagon they were the first (I believe) to provide a Java 1.3 compliant JDK to the Linux masses. I have always presumed they did this 1) because Blackdown’s JDK, though compliant with Sun, was slow as ass and 2) because the Blackdown team, underfunded and understaffed as any volunteer effort usually is, was taking forever to get their JDK up to speed with Sun’s. I am pretty sure the Linux JDK only works on x86, though I definitely could be wrong about that.
Eventually, of course, Sun jumped on the Linux bandwagon and took the x86 version of the Blackdown JDK and rereleased it as the offical Sun JDK for Linux x86. This made lots of Blackdown people mad because Sun did not originally give the Blackdown people the credit, a PR mistake that Sun eventually amended.
Now, as far as I understand it, Blackdown and Sun have for some reason forked their Linux efforts. The only real differences I see are that 1) The Sun JDK is always up to speed with the latest releases for their JDK for Win32 and Solaris while Blackdown’s is obviously not and 2) Blackdown still supports multiple architectures while Sun only supports x86.
As far as I know, IBM has no plans to continue developing a Linux JDK now that Sun has created an official one for Linux.
Hope that clears things up and I hope that if I’m mistaken about anything, someone will comment to clear it up.
Yes! It does! The download site (I went to the top one listed under North America) has binaries compiled with both GCC 2.95 and GCC 3.2, in both the JDK and JRE!
thanks for the clartification… so the myths/truths that fly about suggesting that Blackdown’s Java is optimised for this and that arw wrong? i’ve heard people say that in x86 linux, the blackdown port is faster and can do better things with threads and so on… is this wrong?
tech_user: I really don’t know anything that specific about the Blackdown JDK. I’d imagine, like in any cross-platform project, they have optimizations where they have had time to write them.
— As far as I know, IBM has no plans to continue developing a Linux JDK — now that Sun has created an official one for Linux.
They’re up to 1.4, and seem to be forging ahead.
With all they’re throwing at linux and the java (WebSphere) I doubt they want to trust any of it to Sun.
To Sun, linux=x86. To them porting to PPC and other architectures is not worth the trouble as everyone uses the host operating system (e.g. OS X). So they’ll only cover the corporate platforms. (Redhat, Win32 and Solaris).
Thankfully, Blackdown recognises that linux is more widespread and hopes spread the message of Java to these architectures. I personally have run the arm 1.3 release on the familiar distro (I wanted a real JVM not some personalJava stuff).
Were PPC supported (IBM & your 970, listening?) Mac coders would have the option of switching to Linux during the inevitable delay between Sun releases (betas even) and OSX releases (they’re still waiting for an official 1.4.1 in OS X 10.3, or whenever. – yes I know there is a seeding program to registered participants)
Hotspot is an issue here. Previous versions of the JRE (e.g. 1.3 on ARM) allowed you to run (slowly) without a jit. However in 1.4 and above, hotspot is an integral part of the JVM. Hence porting the latest JRE to other architectures means porting hotspot; from what I hear it’s far from trivial.
The other main role of Blackdown is to focus on areas that Sun neglects, e.g. platform specific features and bugs that aren’t (to Sun) a high priority. (see blackdown’s future plans section of their status page)
Changes then are merged back with Sun’s code to benefit the rest of the Linux community using the ‘official’ Linux Java.
Konqueror doesn’t require a plugin, just a JVM, and yes, this one works.
Not all java applets are compatible with Java 1.4, however.
The BlackDown version was the preferred JVM on RadHat 7.2. When trying to run the Sun version you always got an error on a ‘green_thread’, the BlackDown version worked.
Currently I have seen some results from the Sun and IBM JVM and it seems that the Sun JVM performs better. To see some figures between Sun and IBM, showing that the Sun JVM performes better, look here: http://www.eclipse.org/eclipse/development/performance/21m5/perform… the stange thing is, is that this is published by people working for IBM…
This is the Email I sent to the developers of BlackDown Java:
“Dear Java developers,
I read an announcement on OSNews.com that JDK 1.4.1-01 is available to
the linux community for x86 and SPARC architectures. I am one of the
people who are desperately looking forward to using this version of the
JDK on a PPC platform. I run a national site on Linux for PPC in The
Netherlands and I see that there are a lot of people out there who would
like to have this new version of the Java Virtual Machine on our beloved
Can you, as part of the Java developers team, make our community happy
with a new version of JDK for PPC ? We have to use version 1.3.1 for a
long time now and we feel that it is time to upgrade.
sun’s jdk compiles fine with gcc 3.2.2 as long as you dont use openmotif.
If you dont believe me and are on gentoo linux, just emerge sun-j2sdk
Now I know a bit about the history of Blackdown JDK, and the present situation. And the Sun vs. IBM implementation is extremely important for us – I think IBM dropped the ball on this one.
to the Blackdown team!
Finally a Linux/SPARC implementation of the JDK that is newer than 1.1.8