Programming language and runtime environment that allows compiled Java programs to run unchanged on most hardware and software platforms

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3
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1answer
2k views

Connect to SVN repository with Netbeans using SVN+SSH

I am trying to connect to a SVN server in order to import my project into it with svn+ssh authentication method. I am using the NetBeans IDE (6.8) with subversion plugin installed on Windows XP SP2. I ...
3
votes
2answers
3k views

Cant start Java, error Could not reserve enough space for object heap

Im trying to get Solr up and running, at first I had the JDK.1.6 working fine, then tomcat running fine too. All of a sudden when trying to run Solr for the first time however I get the error message: ...
2
votes
7answers
390 views

Do you consider Java on your Linux server to be a problem? [closed]

If you wanted to use a utility on your Linux (or other Unix) server box, and it required Java, and no other application on your server required Java, would you be turned off that you had to install ...
2
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4answers
5k views

What is a Servlet Container and how to install one?

I am about to order a VPS (virtual private server) from a provider, and I guess I have to install some Servlet Container right? I am about to use SOLR and my website is PHP MYSQL JAVASCRIPT based. ...
2
votes
4answers
2k views

java memory allocation under linux

I'm running 4 java processes with the following command: java -Xmx256m -jar ... and the system has 8Gb memory under fedora 12. however it is apparently going into swap. how can that be if 4 x 256m ...
2
votes
2answers
6k views

Why Tomcat doesn't stop?

When I run command: catalina.sh stop I receive error: org.apache.catalina.startup.Catalina stopServer SEVERE: Catalina.stop: java.net.ConnectException: Connection refused at ...
2
votes
2answers
537 views

How can I avoid press “Enter” during Java Sun (Oracle) 1.6 installation on Linux (CentOS)

It is quite easy to install java sun jdk 1.6.x using xxx.rpm.bin installer from java.com, but it forces you to press "Enter" for the license agreement during installation. This is a problem for me as ...
2
votes
3answers
835 views

VPS : How to deal to servers without swap?

I have recently deployed a java application on a VPS but It keeps crashing because the JVM runs out of memory after a while. I never had this issue on other 'low memory' servers thanks to the swap but ...
2
votes
3answers
5k views

What port is the Websphere app server's admin app on?

I've started Websphere on my local box and I can't remember what port the admin app should be on. Any ideas?
2
votes
5answers
642 views

Can we Uninstall Java on Production Server?

A vulnerability scan on a web server told me that my version of Java needs to be updated. We run .NET web applications on this server, and to my knowledge there is nothing that uses Java. How can I ...
2
votes
8answers
4k views

What are best practices regarding multiple JVMs on a server?

Many third party products require a specific version of the JRE or JDK and many of our servers have multiple duties. Application teams argue they should not care where Java is installed. Most of the ...
2
votes
3answers
3k views

Cannot install JAVA SDK on UBUNTU

Note: I followed all the instructions here: http://blog.taragana.com/index.php/archive/how-to-download-install-jdk-6/ I went to the java.sun website I ran wget on : Java SE Development Kit 6u16, ...
2
votes
3answers
29 views

How can I verify the heap size startup arguments for an active JVM that's running as a Windows service and loading JVM params from registry?

I've got a Windows server with a third-party application on it that runs as a Windows service. The service/application is actually a java virtual machine however it displays in task manager as an exe ...
2
votes
2answers
2k views

CentOS server. What does it mean when the total used RAM does not equal the sum of RES?

I'm having a problem with a virtual hosted server running CentOS. In the past month a process (java based) that had been running fine started having problems getting memory when the JVM was started. ...
2
votes
2answers
4k views

Java: Tomcat slow serving static files?

I'm running an instance of Apache Tomcat (5.5) on a Windows 2008 platform. I think I'm seeing an issue related to concurrent file access / locking. When the number of concurrent HTTP threads is ...
2
votes
2answers
1k views

can you move the java installation to another directory?

I set the environment variable to setup JAVA_HOME. Problem is, java is installed in c:\program files\blah\blah\ (notice the whitespace in the folder path). so this works: "%JAVA_HOME%\bin\java" ...
2
votes
3answers
2k views

How to determine SQL causing Oracle CPU Spikes

I have a J2EE Spring/Hibernate webapp using Oracle 11g for persistence, occasionally in production the Oracle CPU spikes to 100% usage, restarting Tomcat drops the Oracle CPU. I am unable to ...
2
votes
2answers
13k views

How do you install a JDK6 on Solaris10 sparc 64bits?

The installation steps of a JDK6 for: Solaris 32 bits Solaris 64 bits are quite straightforward but: are in two separate documents do not deal with local zone (container) installation do not ...
2
votes
1answer
1k views

Use chef-solo to install Oracle JDK 7

Assume I have the java cookbook and its dependencies downloaded from http://community.opscode.com/cookbooks and can run chef-solo successfully. Is there a command that I can run to install the latest ...
2
votes
1answer
898 views

How to keep Java 7 up-to-date without losing JRE 6?

I have recently found out the hard way that Oracle has decided to silently nuke JRE 6 when a JRE7 update is installed. Is it possible to leave JRE7 on auto-update without breaking JRE6? If not, how ...
2
votes
1answer
3k views

Install Openjdk7 on Debian Squeeze

I've got a server that's running Debian Squeeze and upgrading to Wheezy isn't an option. I need to install version 7 of the JRE as there's some bug fixes in there I require. My options are: ...
2
votes
2answers
2k views

Scheduled task fails, but runs fine when triggered manually

We have a 2008 R2 server with a scheduled task that runs a .bat file which executes a call to a Java app. The task triggers just fine, but stops executing anything after it creates the log file. ...
2
votes
2answers
2k views

JMX connection to Tomcat running on Amazon EC2

My Tomcat 7 process, which I run on a server on Amazon EC2, has settings such as these in CATALINA_OPTS which should allow me to connect for JMX monitoring remotely: ...
2
votes
2answers
4k views

analyse TCP performance by interpreting “netstat -s”

I have executed netstat -s on my dedicated server running debian. I'd like to interprete the results because I'm experiencing connectivity problems with TCP. I don't know how to read these results. ...
2
votes
3answers
9k views

iDRAC6 Virtual Media native library cannot be loaded

When attempting to mount Virtual Media on a iDRAC6 IP KVM session I get the following error: I'm using Ubuntu 9.04 and: $ javaws -version Java(TM) Web Start 1.6.0_16 $ uname -a Linux ...
2
votes
7answers
2k views

Running script in background without sticking to shell

i want to run a shell script remotely via ssh and the ssh shell should end when the script ends. The script itself runs another script whose output is piped to a log file. Example: I run the script ...
2
votes
3answers
2k views

Best way to deploy JRuby?

Background: I'm developing a Ruby web application, and have decided to switch to JRuby for several reasons that I'm not going to mention here. I have experience with servers such as Apache and ...
2
votes
2answers
1k views

What is your experience using Hyperic HQ to monitor a distributed/clustered systems

I've been trying to find a good solution (that can run on Windows) for monitoring/trending/alarming a distributed system comprised of primarly Java technology (Tomcat, ActiveMQ, JBossCache, etc.), but ...
2
votes
1answer
581 views

How to replicate Memcache data among servers

A same question in SO can be found from here . But since I couldn't find any suitable answer, I am asking with additional info. I have many memcache clients but all of them access one memcache server ...
2
votes
2answers
990 views

Block bots by their Java referrer or User-Agent string?

I have been getting a lot of web hits in my logs that crawl most top level pages of my site and show a referrer as a Java version. I see different variants of the Java versions in the referrer, i.e. ...
2
votes
1answer
144 views

Specify a different location to install Java - RHEL6

Is there a way to specify the location where all the installed files would go when installing Java JDK on red hat linux 6? Currently when I follow the steps mentioned in Installation Guide, it ...
2
votes
1answer
85 views

Why would disk reads be heavier than writes with a simple java app that creates many small files?

I've got a very simple java 7 app that reads from a proprietary file format (Hadoop sequencefile) sitting on disk xvdb and creates millions of 2-20kb files on disk xvdf. ByteBuffer byteBuffer = ...
2
votes
1answer
145 views

Time jumps on guest system really shortly

I've got a ESXI-Server and a OpenSuse 10.3 distribution running on it as a guest system. In a java (6_17) application that uses Thread.sleep() to not hog 100% CPU, I noticed that it sometimes never ...
2
votes
1answer
4k views

How to install java-1.7.0-openjdk-devel on RHEL Server 6.3?

I have need of installing a Java 7 development environment on a RHEL 6.3 (system details are below). Following the official OpenJDK directions I tried yum install java-1.7.0-openjdk-devel (as root). ...
2
votes
1answer
2k views

Configuring Tomcat to not load web-app automatically at start up

I have a Java web app which I'm deploying using Tomcat but I'm having some trouble with this. The problem is that my web app has to talk to some native libraries (via JNI) and those libraries do not ...
2
votes
2answers
72 views

Will shared hosting work for my case?

I need to host a JSF application backed by a NoSQL database (Cassandra, which operates on a cluster of nodes). I'm going to purchase a set of VPS to maintain the database server cluster. But to host ...
2
votes
1answer
1k views

Do we need to reboot Ubuntu server after un-installing tomcat6

i am on ubuntu 10.04 server, having tomcat6. because of some reasons i had to un-install it so i used apt-get purge tomcat6 it removed tomcat and config files. now i am trying to install tomcat6 ...
2
votes
2answers
1k views

Setting up APACHE-JAMES Server

I am trying to setup Apache-James Server on Ubuntu, in which I am getting the annoying error: JAVA_HOME not defined correctly We cannot execute I have already referred to the ...
2
votes
3answers
96 views

Resources on Java for Sys Admins? [closed]

I've been fortunate enough to make it four years as an SA without having to administer systems making use of Java. My luck has run up and I am starting a new job and they make extensive use of Java. ...
2
votes
2answers
811 views

Amazon EC2 java installation problem

I'm having a little problem here: I got the amazon free usage tier to test it, launched a ami-465c6932 (Ubuntu 10.10 32bit iirc) on an eu west server. I installed postgresql and made sure it is ...
2
votes
2answers
2k views

Java, Eclipse: How do I pause a running program?

I am running some computation on my Linux box and can't really afford to run it on battery while I drive home. It requires a network connection and currently I am running this stuff on a wireless ...
2
votes
2answers
152 views

Things to know before installing Solaris

I'm about to install a stack on a Solaris box. I have experience installing this same stack on Ubuntu LTS and it has been very simple, but management really wants this to run on a fancy UltraSPARC T1 ...
2
votes
3answers
60 views

java program out of memory before reaching xmx

On a Redhat CentOS 6.4 are only a few process running, using about 3GB RAM (System has 12GB available). One of the processes is a WSO2ESB Server (java), we start it with those parameters: -Xms2048m ...
2
votes
1answer
3k views

OpenJDK or Oracle Java on production server

I'm little bit confused about which implementation is better to use on production server? Are there any reason why not pick OpenJDK?
2
votes
1answer
1k views

Create tomcat war file from static web dir

I created a simple web application that consists of a dir with html, css, js. No server code. For reasons complicated to explain, my administrator insists on turning it into a .war file, so that it ...
2
votes
1answer
86 views

How can I reduce the number of coldfusion threads running?

I have CF running on a mediatemple DV4.0 & it seems to be running WAY more threads than necessary - enough to continuously trip the "running processes" alert that MT provides [and cannot be ...
2
votes
1answer
388 views

How can I persist certificates in Java's cacerts?

We need to have a certificate in Java's cacerts keystore for one of our servers that is authenticated by LDAP. We are using Ubuntu server. We have successfully done this by updating the cacerts file ...
2
votes
1answer
510 views

Hyper-Threading & htop/system-monitor

I'm running a large set of simulations on a quad-core Xenon E5520 with Hyper-Threading enabled. My software automatically detects 8 (virtual) cores and launches 8 simulations to run in parallel. ...
2
votes
1answer
342 views

Is it possible to set Java to update automatically? Pros/cons?

We have a few hundred users and about 40-50 of them need Java for one reason or another. The problem we run into (as have many others online apparently) is that Java seems to want to update all the ...
2
votes
1answer
2k views

TCP Window Size going to 0 / Wget stops downloading?

I have a somewhat complex setup that doesn't work, and I'm struggeling quite a bit to track down the root cause. First of all the big picture: Node backend is a medium size windows azure worker role ...