It's probably too soon to ask this question but I hope someone has already had the same problem as me.
I have to build a jar that run on a centos7, openjdk-7 machine.
I created a docker machine in a ridiculously short time :) but my issue is more a maven one.
My questions is :
How to generate a jar on remote machine (container powered by kitematic on mac for example :p) with the jdk and environment of this machine ?
Any help we'll be welcome.
--- EDIT
I develop on my mac and I would like to launch the build on a "remote" machine which is, in local, my docker container on the kitematic vm.
I think you're just asking how to compile source on your local Mac using a container. If you have boot2docker installed, the following works:
$ docker run -v $(pwd)/java_proj:/java_proj java:openjdk-7u65-jdk javac /java_proj/Test.java
Assuming you have a folder java_proj in your current directory with the file Test.java, this will compile the test file and should place the output in the same folder. We can do this as the boot2docker VM shares your home directory and we can then mount the folder as a volume inside the container. The code will be compiled using the compiler and environment of the java:openjdk-7u65-jdk image.
Related
I have a very basic question about FROM line in dockerfile for a java application, like a spring boot app.
So we write it like:
FROM openjdk:11
ARG JAR_FILE=target/*.jar
COPY ${JAR_FILE} app.jar
ENTRYPOINT ["java","-jar","/app.jar"]
In line 3 we are basically telling docker to use the application jar inside target folder for running the app inside container. Now when a jar is build for a java application, build process takes into account all the needed dependencies like those from jdk or those defined in POM etc.
So then why do we need FROM line? We already have all in our jar, isn't?
The FROM argument describes a base image to use. https://docs.docker.com/engine/reference/builder/#from
An analogy in a non containerized world would be sitting down to a computer freshly installed with some OS and various dependencies already setup for you. Handy!
In this specific case, you are getting an image from OpenJDK. https://hub.docker.com/_/openjdk.
Edit to add detail: As a number of comments state, Java needs the JVM installed on some OS to run a Java program. If you look down at image variants in the docker hub link, you'll see that you are requesting an image with Debian Linux and OpenJDK 11.
I am trying to run java with docker image in gitlab.
Here is my docker file.
FROM java:latest
FROM perl
COPY . /
ENTRYPOINT ["/usr/bin/perl", "/myapp_entrypoint.pl"]
I was able to build docker image successfully and run perl commands but java commands are not working.
My application is a linux application and I am running 'java -version'. I am not getting any output completely blank output for version command.
What would be the issue? Do I need to add anything related linux as I am running 'java -version' as linux command?
You don't specify what OS you're running in your container, but the main issue is that you're blowing away your Java layer with another FROM directive.
From the documentation, emphasis mine:
Each FROM instruction clears any state created by previous instructions.
So I'd espouse a solution in which I install Perl (if I really needed to) after having my base Java image.
However, if you use the base OpenJDK images, Perl comes preinstalled, so that will simplify your Dockerfile significantly.
FROM openjdk:latest
COPY . /
ENTRYPOINT ["/usr/bin/perl", "/myapp_entrypoint.pl"]
I've made my first clojure app and I've built it with leiningen by running lein ring uberjar. I can run this on my dev machine (fedora 23) and I can run this on my ubuntu production machine java -jar tomahawk.jar. I've followed the digital ocean tutorial here that describes how to set up the environment. My supervisor conf is the following:
[program:tomahawk]
environment=TOMAHAWK_DB=$TOMAHAWK_DB
command=/usr/lib/jvm/java-1.7.0-openjdk-amd64/bin/java -jar tomahawk.jar
logfile=/tmp/supervisord.log
directory=/var/www/tomahawk/app
user=www-data
autostart=true
autorestart=true
startretries=3
redirect_stderr=true
stdout_logfile=/var/www/logs/tomahawk.app.log
However, when using this through nginx, i get the error
2016-03-19 23:34:08.594:WARN:oejs.AbstractHttpConnection:/
java.sql.SQLException: No suitable driver found for jdbc:sqlserver:$
at java.sql.DriverManager.getConnection(DriverManager.java:596)
at java.sql.DriverManager.getConnection(DriverManager.java:187)
at clojure.java.jdbc$get_connection.invoke(jdbc.clj:255)
This comes from the com.microsoft.sqldbc4.jar file. However, I can run this standalone jar file, as well as I can run sudo -u www-data env TOMAHAWK_DB=$TOMAHAWK_DB java -jar tomahawk.jar just fine. Also, while this is running, I can hit it through the nginx reverse proxy.
I've searched around and found an unanswered email on the supervisor mailing list from 2011. Why can I only sometimes see the missing jar file?
I've tried putting it inside of the /usr/lib/jvm/.../lib/ext location for my jvm, bundled inside of the jar file, running from Tomcat, etc. I've made an upstart script as well with identical results as well. I am not sure what other paths I can try and was wondering if anyone had any insights.
When I work with JAI from the Eclipse (all the classes specified)
it works very fine, but when I bundle everything in a jar and make a shell script file from that and try to run that script I have a problem with javax.media.jai.OperationRegistry
looking for a initialization file.
Has anyone else seen this problem?
Exception:
java.lang.RuntimeException: Registry initialization file not found.
at
javax.media.jai.OperationRegistry.initializeRegistry(OperationRegistry.java:365)
at javax.media.jai.JAI.(JAI.java:566)
There is something on this page but I was not able to understand.
Any Help?
So the problem is that the JAI jar exported with the Java application do not work on the Linux. We have to explicitly install JAI on the Linux machine for the installed Java application to use.
The one solution that we found out is we exported our Java Application into a jar file and created a installation script, which when run on the Linux machine install the JAI first and after that it install our application.
So this is a one time installation process while installing the application on any fresh Linux machine.
I am new to Java.
Basically, I developed a java projects which contains multiple Java packages inside Eclipse. The project runs OK on my desktop with a redhat Linux installed. However, I need to run it on a more powerful Linux server (redhat enterprise Linux) which does not have X11 installed. Therefore, it is impossible to run Eclipse on that server.
Is it possible to do that? If so, how can I move the entire project to that server including the input and output folders?
Thanks
In Eclipse use the "Export Runnable Jar" option. Highlight your project then click file->Export, choose Java, choose Runnable Jar file. Otherwise you can also use the javac compiler to compile your project and run it with the java command and your main class.
You will need to install the JRE on the machine you want to run it on. This can be done with the following command:
yum install java-1.6.0-openjdk*
Once you have java then it is simply a matter of executing your application. I would recommend using eclipse to compile your project to a jar and use the following command to execute it:
java -jar *JarFileName*.jar
Running Java is nothing to do with Eclipse . You can run your java program in linux machine by opening terminal .
Step1;- Set your JAVA_HOME in your bash profile .
Step2:- open terminal , go to the folder or package where your main program is present.
Step 3:- compile it using javac -cp lib.jar Filename.java
Step 4:- After compilation class file will be available , run it using java filename.java
Usually IDE like eclipse is for development not for running the application , but Linux version of eclipse is also available
http://eclipse.org/downloads/?osType=linux