Yep, in a way the jvm is doing the one thing that native platforms haven't. That is provide a universal (in java land at least) interface in java bytecode to languages running within the jvm.
Think about the ffi annoyances with c->c++->other-lang, its so simple in jruby to use clojure libraries, or rhino for some other stuff, or vice-versa, or whatever.
And I'm not a java fanboy, but that fundamental aspect of the jvm as a platform is crazy cool.
The same is true of Mono/.NET as well; in fact the CLR was designed for this and has features the JVM lacks, such as parametric types, invokedynamic, tail calls, etc.
If you're into functional programming the CLR is the runtime to beat.
I think MS missed a beat here, if they had pushed for the .Net CLR to be a first class and equal citizen on OS X , iOS and Linux they would probably be in a much more relevant position in the future.
Not the mono runtime; the fact that there are two runtimes.
The official MS one, and the Mono one, and although they're kind of compatible, in that your C# can be compiled to run on either of them (mostly, sometimes, if you haven't done anything fancy, if you're not using MVC, if you're not using a UI layer that isn't portable, if the version of mono you're using from A is the same as from B ( >_> unity...) ), this is FAR away from the java JVM, where you can ship an application that just runs on all the platforms.
Don't get me wrong, you can do that with C# too... if you use Mono only, and flip off the official M$oft .Net runtime.
...but the mono runtime is behind the curve, always playing catchup to the 'official' runtime, supporting a subset of the features, and everywhere runs different versions of the mono runtime. It's a mess.
You've got to admit, the JVM is 100% superior in this regard.
I suppose you've never had a problem with two JVMs that ran a package but didn't behave quite the same way, to disastrous effect? Or dealt with software that only worked with one very specific version of the JRE that was exclusive from the equally specific JRE required by another bit of software?
To compare Mono to the MSFT CLR and call it rubbish by way of contrast to Java-land strikes me as hilarious. I'll choose .NET every time given that choice...
>I suppose you've never had a problem with two JVMs that ran a package but didn't behave quite the same way, to disastrous effect?
Only at the very limited level of "versions of the JVM before x have a bug that makes this package not work.
>Or dealt with software that only worked with one very specific version of the JRE that was exclusive from the equally specific JRE required by another bit of software?
No, never. I know one should never overestimate enterprise software vendors, but you'd have to try really hard to make something that crap.
I use HotSpot and JRockit. There's performance differences between the two but I've yet to run into something that works on one and breaks on the other.
Well there's weirdness between Oracle and OpenJDK, thought to be fair I haven't had a problem with OpenJDF for a while. I don't imagine it's that unusual to find a server running Oracle JVM though.
In all seriousness most Java devs. regard the OpenJDK package as "that weird jvm that comes with the OS that nobody actually uses". First thing we do is download the latest JDK from Sunoracle.
What? That's not true. "Most Java devs" (that I know) prefer Linux and primarily utilize OpenJDK for development. (Deployment is a mess left to other people).
Really? No one uses Linux? And you're talking about Java and JVMs? That just looks silly.
I only develop on Linux, think you got confused by the way I phrased it. I meant that hardly anyone uses the OpenJDK package, not that hardly anyone uses Linux.
I'm (among other things) a Linux Java dev, and for what is worth from my anecdotal point of view, neither me nor anyone I know users OpenJDK. Both development and deployments happens with Oracle stuff.
No, it wouldn't. Let's be honest, people would say it's from Microsoft and not use it for that very reason. Could be better than JVM and still most wouldn't use it. Linus was right, the hatred of Microsoft is a disease, and a lot of people in the open source community suffer from it.
Microsoft cast it upon itself. When you cry wolf all the time, nobody comes to help.
Microsoft can't let go. They can't say "this code is now open and no strings attached". They can say "but not really". They can say "but don't touch anything". Microsoft can't open.
What they can do is okay for consumers. Consumers will download whatever software available and use that. Developers? Hell no. Developers don't trust openness that can be revoked. Because this means their product stops working.
Then how do you explain that with mono? It's open source, but since it used MS's specs, with OS license, it has been vilified by the open source community. The reality of the matter is that while developers like to think they're rational, they're just as emotional as any non-developer. Their decisions are driven by emotions, by their hatred for MS or some other company / technology, hence the disease Linus was talking about.
How is it vilified? De Icaza loved it and pushed everywhere. Gnome played with it.
But mono is not .Net.
I mean, if you look at Java, there is a very strict process which a JVM implementation must undergo in order to be called Java (and still there are a dozen of such implementations). It means it behaves predictably and have every one of the required APIs.
And most of development tools are written in Java.
On the other hand, with .Net we have Microsoft implementation on Windows - and we have everything else. .Net on Windows has a massive number of APIs (many of those system dependent), hatches into COM, can easily use native code and libraries.
Most .Net tools only work on Windows and are written as a mixture of native code, bytecode and COM.
And mono is a second class citisen forever. It will never have all those limitless APIs and will never have all the tooling.
It is extremelly unlikely that developers (of proprietary, in-house, server software) who use OS X or Linux as their development environment will ever adopt it. Nobody likes to be second class. Programming is painful enough even without that.
It has been, and it still is, thankfully to a somewhat lesser degree. Even Stallman said "we should discourage people from writing programs in C#". This, of course, is just the tip of the iceberg.
Whether .NET is different from Mono is not what I argue. Mono brought a MS-inspired technology to Linux so they got under the MS hatred umbrella. There was and still is a purely knee-jerk / emotional reaction to whatever they bring to the table.
I also remember how Stallman praised the starting of two GNU projects to reimplement .Net.
Anyway, Stallman is not a good example of vilifying anything. He's the strictest man in town. He is afraid of everything. Rightfully so. But he's not a representative sample of the community.
I don't think that necessarily true. Maybe it is for "the open source community" in terms of Stalanites.
OTOH lots of people use and love OSS including very profit driven startups and Apple "fanboys". Being able to write C# using Visual Studio under OS X and deploy to Linux would be killer app for a lot of startups and of course whatever stack gets used by the popular startups will be lionised.
It uses GTK#. What do you expect, WPF is a Microsoft licensed tech, you can't blame Xamarin for not stealing it. A GUI written to GTK# is portable to ios, Android, OSX, Windows, and Linux, and a bunch more marginally obscure targets. Every platform under the sun.
Scala provides tail call optimization and invoke dynamic has been in the JVM for years (since JDK7). The JVM is also considerably faster than the CLR and unlike Mono is heavily used in industry.
Why would MS make .NET really cross plateform ? MS is here to sell Windows and Windows Software, nothing more. Mono is an unofficial hack and can be shut down anytime by Microsoft , i would not bet my career on that stuff.
Think about the ffi annoyances with c->c++->other-lang, its so simple in jruby to use clojure libraries, or rhino for some other stuff, or vice-versa, or whatever.
And I'm not a java fanboy, but that fundamental aspect of the jvm as a platform is crazy cool.