A Java virtual machine (JVM) is a virtual machine that can execute Java bytecode. It is the code execution component of the Java platform.
2
votes
1answer
170 views
How to create own programming language based on JVM? [on hold]
I am curious about how to create a programming language based on JVM so I have tried to get some info online, but the information I got are quite fragmented. What I found are mostly information ...
15
votes
1answer
797 views
Is it *ever* okay to catch StackOverflowError in Java?
I used to think that it's not, but yesterday I had to do it. It's an application that uses Akka (an actor system implementation for the JVM) to process asynchronous jobs. One of the actors performs ...
4
votes
3answers
143 views
Java Compiler and VM Compatibility
A co-worker and I recently had a discussion about Java versions and the JVM. I use Java 7 but we use Java 6 for our client (while he says that some are still on 5). My immediate thought was, why can't ...
12
votes
5answers
765 views
What makes JVM so much versatile to support so many JVM languages?
JVM supports so many languages other than Java like Groovy,Clojure,Scala etc which are functional languages unlike Java(I am referring to Java before Version 8 where Lambda's are not supported) that ...
4
votes
2answers
211 views
How are Scala Traits implemented in the JVM?
I have been reading about traits in Scala. They are pretty amazing. I am curious how they extend a class without actually resulting in multiple inheritance. I know that the JVM doesn't support ...
-2
votes
1answer
170 views
Can we call PLC as virtual machine? [closed]
I want to implement some byte code mimics in 8051.
I used 24c16 as memory unit and took instructions from computer COM port and store it in 24c16 memory and later on in running mode it translates ...
0
votes
2answers
243 views
JVM vs operating systems [duplicate]
Recently i was re-visiting the basic concepts of operating systems. Since I am a java developer, I have inherently started looking at everything from java point of view. I am also reading 'Inside the ...
1
vote
5answers
424 views
Java heap space
In Java/JVM, why do we call the memory place where Java creates objects as "Heap"?
Does it use the Heap Data Structure to create/remove/maintain the objects?
As I read in the documentation of Heap ...
3
votes
1answer
265 views
Does current JIT optimize generated machine codes for branch prediction based on runtime statistics?
Some JVMs would compile Java byte code into native machine code. We know that there are lots of optimizations we could apply for that. Recently, I also learn that a branch operation may block the CPU ...
21
votes
4answers
2k views
What limitations does the JVM impose on tail-call optimization
Clojure does not perform tail call optimization on its own: when you have a tail recursive function and you want to have it optimized, you have to use the special form recur. Similarly, if you have ...
1
vote
3answers
158 views
Java Terms that are Plagued with Vaguery [closed]
What's the difference between a Java Process (what your OS sees) and a JVM? Are they one in the same or are they actually different?
How are the JRE and JDK different (in purpose and file content), ...
2
votes
2answers
238 views
How to devise instruction set of a stack based machine?
Stack based virtual machines like CLR and JVM has different set of instructions. Is there any theory behind devising the instruction set while creating a virtual machine? e.g. there are JVM ...
8
votes
4answers
1k views
How does the Java Virtual Machine execute code written in other languages?
Since Java 1.6 the JVM can run a myriad of programming languages on top of instead of just Java. I conceptually understand how Java is run on the Java VM, but not how other languages can run on it as ...
8
votes
1answer
778 views
How can Java be improved so that it no longer needs to perform type erasure?
The official Java tutorial on generics explains type erasure and why it was added to the compiler:
When a generic type is instantiated, the compiler translates those types by a technique called ...
11
votes
4answers
2k views
Approaching Java/JVM internals
I've programmed in Java for about 8 years and I know the language quite well as a developer, but my goal is to deepen my knowledge of the internals. I've taken undergraduate courses in PL design, but ...
3
votes
2answers
259 views
Are there any mixed stack register virtual machines?
I was reading about JVM and Android, and the technical differences between them, and one important it that one VM was stack based, and the other register based.
I studied assembler in College, & ...
-4
votes
4answers
458 views
Are Java developers becoming less important as JVM/JIT capabilities grow?
(I am asking this from a low latency perspective, but I guess the question applies in normal business domains).
I am deciding whether to try and specialise in C++ or Java for low latency.
My issue ...
2
votes
4answers
1k views
Learning more about Java Hotspot/JVM and JIT? [closed]
On SO I was told there aren't really any good sources to learn about the JVM (Hotspot in particular) and JIT.
Is this true and if not, could I have some recommendations for books/websites/oracle ...
1
vote
2answers
429 views
Converting ANTLR AST to Java bytecode using ASM
I am currently trying to write my own compiler, targeting the JVM.
I have completed the parsing step using Java classes generated by ANTLR, and have an AST of the source code to work from (An ANTLR ...
2
votes
4answers
400 views
Static methods on a web context
What happens when concurrent requests call the same static Java method running on an application server?
Say that a method run takes 2 seconds and receives 100 calls in a given second. The method ...
3
votes
1answer
110 views
What is richochet frames based hotspot jvm?
In order to implement JSR 292, a.k.a. invoke dynamic, something called richochet frames is introduced into the hotspot vm. I'd like to know more about it, such as invoke dynamic itself, how richochet ...
6
votes
5answers
435 views
Modern languages and the JVM
Many modern programming languages (Scala, Erlang, Clojure, etc.) are targeting the JVM. What are the main reasons behind that decision?
JVM's maturity?
Portability?
Because JVM simply exists, and ...
3
votes
1answer
222 views
Incanter for real world statistical projects
I'm interested in statistical computing. R is a leader platform obviously but what about Incanter?
Incanter is at the top of my list since I'm a Clojure and JVM guy.
Do you have any real world ...
7
votes
3answers
515 views
How safe it is to do minor JVM upgrades?
I have been working on the JVM for years and I have very rarely experienced a JVM crash ... that is until approx 6 months ago.
Since that I have experienced approximately 5 JVM crashes resulting ...
18
votes
3answers
2k views
Is Clojure, Scala and other restrained by the JVM vs CLR
The Java implementors seem slow to adopt language improvements, for example compare C# with full closures, expression trees, LINQ etc.. to Java, and even the push back of some stuff to Java 8 will ...
4
votes
3answers
287 views
How do I get feedback about whether escape analysis had any affect on my code or not?
One problem I have with compiler optimization is, that I actually never know what the compiler (or in this particular case the Jit) does with my code. So is there any possibility for me to know ...
9
votes
2answers
697 views
Java and JVM license
Does Java license allow other companies to create their own versions of Java language or just implement it accurately? Same question about JVM.
I heard about Sun suing Microsoft for changing their ...
7
votes
6answers
2k views
Is there a clear leader amongst JVM-based languages? [closed]
What is the current status of these projects, and has any one (or two) emerged as a clear leader?
To demonstrate my motives for asking this question, cast your mind back several years. Prototype and ...
3
votes
4answers
553 views
How to disseminate Scala?
With the announcement of Ceylon, and after observing the slides describing its intent and feature list, I reckoned this language to be a Scala competitor.
Furthermore, as a Scala programmer, I can ...
2
votes
3answers
1k views
What is the difference between instantiating and loading a class in Java?
In Java world, there are some scenarios where I see developers used to load the class rather than instantiation. What is the difference between instantiating and loading a class?
5
votes
10answers
330 views
Does your workplace allow the use of multiple, interoperable programming languages?
Since now there are several good languages that target the JVM and can interop with Java with varying degrees of painlessness, and likewise for the CLR (especially with the recent addition of F# as an ...
4
votes
4answers
1k views
What is the best JVM Lisp for writing a video game?
This video game won't be super fancy, but the idea is for it to have a moderate amount of functionality. Thoughts?
Edit:
Fast would be nice.
Another edit:
This is what I want:
To be able to ...
5
votes
9answers
578 views
Is there any evidence that one of the current alternate JVM languages might catch on?
There's been a lot of enthusiasm about JRuby, Jython, Groovy, and now Scala and Clojure as the language to be the successor to Java on the JVM.
But currently only Groovy and Scala are in the TIOBE ...
0
votes
3answers
1k views
Anyone know a decent JVM profiling tool for IBM JVM on AIX?
I am tired using hprof and some lame tools that are available in AIX for JVM profiling. None of the tools like Netbeans Profiler and visualvm works on JVM on AIX. It will be great if anyone knows a ...
8
votes
5answers
398 views
How is the JVM and Java's WORA different from other high level languages?
In the Java world, we often talk about the JVM, and when Java was new it had the supposedly killer feature of "Write Once, Run Anywhere."
From the way people talk and write, this seems different from ...
1
vote
2answers
264 views
What would be the best way to get Apple to donate their JVM-work to OpenJDK? [closed]
It has been announced that Apple deprecates their JVM. It is a really nice piece of work giving an excellent user experience for Swing application on OS X, and it would be a pity if it just went ...
10
votes
3answers
428 views
Is Apple getting out of the general purpose development platform business?
I've been doing general ANSI C/Console C++/Java/Web development on Mac hardware for about ten years. I make no claims of objective superiority over other platforms, it just satisfies my personal ...
5
votes
3answers
2k views
Jython and JRuby vs. Groovy (and Java)
I am very interested in Python for programming on the JVM, and I've worked in Java and Ruby (not JRuby) a lot, and to a certain extent in Groovy.
What are the limits to the Java-Jython and Java-JRuby ...
