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

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1answer
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How to Install Apache Solr / Java on CentOS?

I've seen only one or two tutorials for installing Solr, and particularly Java, on a CentOS machine, and they seem to be overly complex; heck, I can't quite figure out which version of Java (it seems ...
3
votes
2answers
4k views

Which performance metrics to monitor on a JVM?

I want to do some performance monitoring on our JVMs. What would be interesting to monitor besides the obvious things I already have on my list ? JVM Free/Total memory GC rate (how many per minute) ...
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votes
3answers
2k views

Installing Java Runtime for a Server: Something better than std JRE package?

I need to install a Java runtime on server machines. The JRE package from Sun acts as if I'm running on a client machine -- it installs WebStart, Auto Updating, probably browser hooks, and other ...
3
votes
2answers
2k views

What Sun Web or App Server config can cause “Due to a temporary error the request could not be serviced”

I'm not the system administrator for this server but I'm trying to help the group who are sys admins to find a fix quickly. For this reason, I don't have access to all of the server configuration ...
3
votes
1answer
106 views

Enable HugePages on Linux for multiple services/processes

On one of my Debian machines I'm running a service on a JVM and a MySQL instance. I have enable the HugePages following various online guides but I'm having a problem. Here is my configuration: ...
3
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1answer
887 views

Load balancing glassfish v4.0 CLUSTER with apache HTTP server: Location of apache

I am teaching myself to build clustered Java EE 7 applications. I am focused on Glassfish Server v4.0. Based on the official documentation (Chapter 7 page 133) , Glassfish can be loadbalanced using ...
3
votes
1answer
2k views

“remote file operation failed” on remote UNIX slaves since upgrading to Jenkins 1.502

Since upgrading to Jenkins 1.502, any jobs using git on remote UNIX slaves launched by SSH fail with hudson.util.IOException2: remote file operation failed: /var/ciworkspaces/web/workspace/DFT.BA ...
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votes
3answers
2k views

CPU/JVM/JBoss 7 slows down over time

I'm experiencing performance slow down on JBoss 7.1.1 Final. I wrote simple program that demostrates this behavior. I generate an array of 100,000 of random integers and run bubble sort on it. ...
3
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1answer
3k views

How to configure Glassfish + NGINX to serve static files with NGINX?

I have a EC2 ubuntu with Glassfish v3 + Nginx setup to host my java web application. This application is deployed as a WAR file to Glassfish . The NGINX is currenty passing all request to the ...
3
votes
1answer
4k views

Clearing Java certificates cache (force reload certificates)

A simple question here. One application gave me this exception when trying to access a website with a expired certificate: java.security.cert.CertificateExpiredException So, I renewed the ...
3
votes
1answer
2k views

Java hangin and crashing on centos 6

I'm having problems with running java programs on my VPS. symptoms: Starts and runs for a bit and then just hangs there without any cpu use. Usually has different amounts of memory allocated. Shows ...
3
votes
1answer
466 views

java.lang.OutOfMemoryError on ec2 machine

I have a java app on a large instance that will spawn up to 800 threads. I can run the application fine as user "root" but not as another user which I created. I get the deadly. ...
3
votes
1answer
81 views

Orcale Java SE Critical security Patches on the 7th, do I have to update Java all the Linux boxes that host our apps?

according to Oracle, "All these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a network without the need for a username and password. " Does this ...
3
votes
1answer
306 views

SysRq, task list and missing processes

I've been troubleshooting a pretty difficult issue on Linux where a JVM appears to hang. As part of the investigation, I've been trying to capture the list of current tasks and their state using one ...
3
votes
1answer
3k views

Sun-JRE on CentOS-4.8 RPM error: post-install scriptlet failed, exit status 5

I have a server with CentOS 4.8 installed. The provided is rubbish, but there's only a few months left, and they're busy being sued by Chase bank, so I doubt I can get CentOS 5. I wiped the server ...
3
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2answers
1k views

Is the Cloud ready for an Enterprise Java web application? Seeking a JEE hosting advice

Greetings to all the smart people around here! I'd like to ask whether it is feasible or a good idea at all to deploy a Java enterprise web application to a Cloud such as Amazon EC2. More exactly, ...
3
votes
1answer
934 views

Configuring a Jetty web application on a different port

I'm brand new to Jetty. I'd like to ask if its possible to have Jetty listening on port 8080, however where specified, serve a specific web application under say /var/jetty/webapps/<appname> ...
3
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1answer
520 views

how to configure tomcat6 for ubuntu

i have installed apache tomcat6 for ubuntu 9.04 recenty.But it seems that some API's like servelet and http are not included althogh i have installed openJDK 1.6. somebody advised me to set JAVA_HOME ...
3
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2answers
1k views

Free java hosting? [duplicate]

Possible Duplicate: Anyone know of any Free Java hosting services? Could anyone tell me some free hosting on which I can run my java web application even for a day? I don't want free ...
3
votes
1answer
2k views

ActiveMQ with persistence in a database

Are any of you running ActiveMQ with persistence in a database? Even better, in an Oracle database? We're wanting to replace our current JMQ uses with ActiveMQ. The plan is to have two machines ...
3
votes
1answer
36 views

Remove all sites from allowed list for plugin in IE via GP

I would like to remove all sites from the list of approved sites for a plugin in Internet Explorer as described here but I would like to do so via Group Policy. Is this possible? I know I can disable ...
3
votes
1answer
4k views

Signing a Java Deployment Rule Set JAR using AD Certificate Services

I am tasked with deploying Java 7 Update 55 along with a Java Deployment Rule Set to all Active Directory Windows clients. I've managed to get a solid Java software deployment setup but I'm now ...
3
votes
1answer
329 views

SNMP query - operation not permitted

I am working on API that reads a lot of data via SNMP (routes, interfaces, QoS policies, etc...). Lately, I have experienced a random error stating: Operation not permitted Now, I use SNMP4J as ...
3
votes
1answer
112 views

How to determine what websites or local applications are using JVM/JRE

We run a large Windows shop -- tens of thousands of workstations. Most have a version of the Sun/Oracle Java Virtual Machine (JVM) installed. With all the security issues around the JVM, we'd like to ...
3
votes
1answer
626 views

Is Winpcap able to capture all packets going through a Gigabit NIC without missing any packets?

I want to use Winpcap to capture all network packets going through a Gigabit NIC of a server. Assuming that I am able to utilize the network link up to 100%, the maximum network speed is 1000Mbps. If ...
3
votes
1answer
169 views

HTTPS Connection error

I am trying to connect to a servlet from usinghttp url connection,i.e http://localhost:9481/test/NewServlet. It worked fine for me. Now I want to connect using https://localhost:9481/test/NewServlet. ...
3
votes
1answer
546 views

What are the best practices for monitoring and alerting for low level JVM metrics?

I'm looking to set up monitoring and alerting for java server based app and want to find some best practices for monitoring JVM specific metrics and for designing alerts based on those metrics. So ...
3
votes
2answers
735 views

Getting syslog-ng to recognize a java stacktrace

We are using the log4j SyslogAppender to send our logging statements to syslog-ng. Once the messages are in syslog-ng, we are having trouble getting syslog-ng to recognize that a stacktrace goes with ...
3
votes
2answers
4k views

Access keystore on Sun ONE Webserver 6.1 for 2048 bit key length SSL

We want to get 2048 bit key length CSR requests. The browser based GUI provides us with a 1024 bit CSR and I don't know how to change that. It seems that 1024 bit key lengths will no longer ...
3
votes
1answer
2k views

Kill FINished sockets (using libpcap - tcpdump/tcpkill)

I'm trying to create a small service that monitors and kills sockets which have the FIN flag. I can get them with tcpdump (I also tried tcp[13] & 1): tcpdump "tcp[tcpflags] & tcp-fin != 0" ...
3
votes
1answer
375 views

high level design of sms transaction handling system

I have been tasked with designing a system do handle SMS transactions. Transactions come in form of HTTP requests from a service provider. In the process of handling transaction, system in question ...
3
votes
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 ...
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votes
2answers
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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: ...
3
votes
2answers
3k views

Where does Java save proxy details?

My question is as the title states really. But to give a bit more detail as to what I would like to know, basically we have a small group of users who wish to create small video tutorials to ...
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votes
5answers
6k views

Unable to find javac after installing OpenJDK 1.6 and 1.7

I am currently at a loss as to why this is happening. I did some basic research by running: whereis javac -and- find / -name javac ...and I came up with nothing I searched the web for answers but ...
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7answers
407 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 ...
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3answers
3k views

Is there a way to use Java and PHP on the same Apache server or at least, same port?

I am pretty new to Java for Web and my question is if I can use Java and PHP together? I know I can use them together, let's rephrase the question, is there a way to access them at the same port? ...
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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
3answers
2k views

Ubuntu: downgrading Subversion from 1.6 to 1.5

I installed Jaunty Alpha, and along with came Subversion 1.6. My IDE (Intellij Idea 7) does not support Subversion 1.6, so I would like to downgrade my Subversion back to version 1.5. How can I do ...
2
votes
2answers
8k 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
616 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
865 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
5answers
805 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
5k 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 ...
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votes
2answers
185 views

Is it safe to deply java 7 se on my network? Is java 7 compatible with java 6?

I am doing some sysadmin work for a small non-profit with about 20 windows XP PCs. I am performing standard maintenance as well as some other work. I am confused about java 7. For consistency sake I ...
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votes
2answers
4k views

unable to install sun jdk on ubuntu

I have Ubuntu 12.04 x64 and I'm trying to install sun jdk for opennms. sudo apt-get install sun-java6-jdk when i run above given command i get following msg: root@fido:~# sudo apt-get install ...
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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
2k 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" ...
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3answers
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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
4k views

JDK install - no matching plugin

I'm trying to install JDK on my remote Debian box. I've been following the directions at this page. Problem is, the make-jpkg fails. Here's the output I get (plus the version of java-package I'm ...