I'm using an ICEFaces application that runs over JBOSS, my currently heapsize is set to -Xms1024m –Xmx1024m -XX:MaxPermSize=256m what is your recommendation to adjust memory parameters for JBOSS AS 5 (5.0.1 GA) JVM 6? ...
Hi, I know that local variables and paramters of methods live in stack, but I not able to figure out where does actually methods live in case of Java? If I declare any Thread object like: Thread t=new Thread(); t.start(); So it means I've created a separate calling of methods apart from main method. What does it mean? Does it mean c...
I've got my hands on an old Microsoft J++ project that uses some old Microsoft-specific things from the Microsoft Java Virtual Machine (now deprecated and unsupported). It uses additional things from the old Microsoft Java Development Kit, which I can't find anywhere on the web. It seems the best route forward is to migrate this project...
Hi can you please let me know in which language the Java compiler, virtual machine (JVM) and java is written. ...
How does google app engine's sandbox work? What would I have to do to create my own such sandbox (to safely allow my clients to run their apps on my engine without giving them the ability to format my disk drive)? Is it just class loader magic, byte manipulation or something? ...
This is a followup to my own previous question and I'm kind of embarassed to ask this... But anyway: how would you start a second JVM from a standalone Java program in a system-independent way? And without relying on for instance an env variable like JAVA_HOME as that might point to a different JRE than the one that is currently running....
Peeps, I'm hosting our dev env on a virtual server over at Mediatemple - the $50 bucks a month kind. Our application does some fairly memory intensive processing and on the last run, ran into the OutofMemError. Apparently increasing the JVM size using the usual methods of setting JAVA_OPT or CATALINA_OPT in the setenv.sh file doesnt...
Hello, There is a "NameAndType" structure in the constants pool in .class file. It is used for dynamic binding. All methods that class can "export" described as "signature + return type". Like "getVector()Ljava/util/Vector;" That breakes my code when return type of the method in some .jar is changed, even if new type is narrower. ...
What is the current state of Java's transition to an open source license (which Wikipedia lists as the GNU General Public License / Java Community Process)? Java being inclusive of many things, including: The JVM The JRE The JDK The Core Java Libraries JavaME JavaEE I've heard/read various things, but never seen it laid out in a s...
I know this question isn't exactly a programming question, but it will affect how we program one of our products, so i guess it might be close enough. Do you guys still see the Microsoft JVM (Java 1.1) on client computers anymore? I havent found much info on this particular JVM online... Anyone know of a good resource to find this typ...
I'm looking for a tool to run java server processes as daemon services in Linux (and potentially on Windows and other OS's). I'm looking for the best practices when it comes to how to build production capable scripts and launch configuration. I'm familiar with best practices when it comes to a project's build, using Apache Maven, or som...
If I compile an application using Java 5 code into bytecode, are the resulting .class files going to be able to run under Java 1.4? If the latter can work and I'm trying to use a Java 5 framework in my Java 1.4 application, is there anything I should watch out for? ...
I'm looking for free to use phonetic/pronounceable password generator written in Java (or any JVM language, which can be called from Java). Ideally the generator would accept criteria for the passwords it creates, eg: minimum length minimum number of non-alpha characters This would be used in a commercial, distributed applicatio...
I've had this troubling experience with a Tomcat server, which runs: our Hudson server; a staging version of our web application, redeployed 5-8 times per day. The problem is that we end up with continous garbage collection, but the old generation is nowhere near to being filled. I've noticed that the survivor spaces are next to inex...
Below is a part of the hs_err_pid Heap PSYoungGen total 13888K, used 9807K [0x8a330000, 0x8b140000, 0x914f0000) eden space 13504K, 69% used [0x8a330000,0x8ac67710,0x8b060000) from space 384K, 96% used [0x8b0e0000,0x8b13c6e0,0x8b140000) to space 448K, 0% used [0x8b060000,0x8b060000,0x8b0d0000) PSOldGen total 115456K...
I'd like to know how to get hold of the kind of Operating System the jvm is running on. It has to be "secure" as well, so System.getProperty("os.name") is not really an option because it can be trivially circumvented with the -D directive. By "secure" I mean nontrivial to circumvent. It's for a desktop application. The user could always...
Are there any published reports on the market penetration of Java? ...
If I have the following: class A { public A() { } public static void foo() { System.out.println("foo() called"); } } public class Main { public static void main(String [] args) { A a = new A(); a.foo(); // <-- static call using an instance. A.foo(); // <-- static call using class } } Are there any problems that ma...
My JVM crashed the and the hs_err file showed that it crashed while attempting to load a class. Specifically while trying to memcpy ([libc.so.6+0x6aa2c] memcpy+0x1c). I looked at the .class file and was able to determine what class was being loaded. But can any one tell me what could cause this or how i could determine more about t...
Hey, I am studying for a java exam and on a past exam the lecturer asked this question and im wondering if someone can help me. "In the context of java explain threads. Give an example of when you might use a thread. Name two java virtual machine threads." The first two parts of the question are easy enough but the part about naming th...