Develop Reference

Use docker-machine create from java

I have an application that (I want to) uses Java to start and stop Docker containers. It seems that the way to do this is using docker-machine create, which works fine when I test from the command line.
However, when running using Commons-Exec from Java I get the error:
(aa4567c1-058f-46ae-9e97-56fb8b45211c) Creating SSH key...
Error creating machine: Error in driver during machine creation: /usr/local/bin/VBoxManage modifyvm aa4567c1-058f-46ae-9e97-56fb8b45211c --firmware bios --bioslogofadein off --bioslogofadeout off --bioslogodisplaytime 0 --biosbootmenu disabled --ostype Linux26_64 --cpus 1 --memory 1024 --acpi on --ioapic on --rtcuseutc on --natdnshostresolver1 off --natdnsproxy1 on --cpuhotplug off --pae on --hpet on --hwvirtex on --nestedpaging on --largepages on --vtxvpid on --accelerate3d off --boot1 dvd failed:
VBoxManage: error: Could not find a registered machine with UUID {aa4567c1-058f-46ae-9e97-56fb8b45211c}
VBoxManage: error: Details: code VBOX_E_OBJECT_NOT_FOUND (0x80bb0001), component VirtualBoxWrap, interface IVirtualBox, callee nsISupports
VBoxManage: error: Context: "FindMachine(Bstr(a->argv[0]).raw(), machine.asOutParam())" at line 500 of file VBoxManageModifyVM.cpp
I have set my VBOX_USER_HOME variable in an initializationScript that I'm using to start the machine:
export WORKERID=$1
export VBOX_USER_HOME=/Users/me/Library/VirtualBox
# create the machine
docker-machine create $WORKERID && \ # create the worker using docker-machine
eval $(docker-machine env $WORKERID) && \ # load the env of the newly created machine
docker run -d myimage
And I'm executing this from Java via the Commons Exec CommandLine class:
CommandLine cmdline = new CommandLine("/bin/sh");
cmdline.addArgument(initializeWorkerScript.getAbsolutePath());
cmdline.addArgument("test");
Executor executor = new DefaultExecutor();
If there is another library that can interface with docker-machine from Java I'm happy to use that, or to change out Commons Exec if that's the issue (though I don't understand why). The basic requirement is that I have some way to get docker-machine to create a machine using Java and then later to be able to use docker-machine to stop that machine.

As it turns out the example that I posted should work, the issue that I was having is that I was provisioning machines with a UUID name. That name contained dash (-) characters which apparently break VBoxManage. This might be because of some kind of path problem but I'm just speculating. When I changed my UUID to have dot (.) instead of dash it loaded and started the machine just fine.
I'm happy to remove this post if the moderators want, but will leave it up here in case people are looking for solutions to problems with docker-machine create naming issues.

Karaf command not found exception how to troubleshoot?

Downloaded karaf 4.0.9 just following getting started doc but keep getting this
org.apache.felix.gogo.runtime.CommandNotFoundException: Command not found: feature:install
whenever i try to do feature:install wrapper from shell
Finding it very difficult to find any help or doc how to trouble shoot? is it a permissions thing? I chowned everything to the same user for simplicity...
Is distribution missing a library? Where do i get it/put it?
New to karaf... Following this: http://karaf.apache.org/manual/latest/#_installation
Just trying to get some basic JDBC/JMS stuff working, install drivers, recieve some msgs, query db, etc

Spent a few hours of reading docs + trial and error to figure this out:
ssh karaf#localhost -p 8101
Will get you full admin shell, apparently this isn't available if you just ./shell from KARAF_HOME/bin

You can check your configurations in users.properties in karaf/etc folder .
Open karaf shell using admin rights.
Start Karaf shell from its bin folder.
Now run karaf console using below command.
ssh username#localhost -p8101
now you can run any command of karaf shell.

Starting Mule for remote debugging without modifying wrapper.conf

I'm stuck on Mule version 3.4.0 due to requirements at work. I'm writing a service script to manage the service lifecycle of Mule and would really like to be able to have it hang and wait for a debugger to connect based on whether a certain option is present in the parameters.
I'm comfortable with Bash and implementing this, but I'm having an extremely hard time trying to get Mule to pass along the
-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=9989
to the underlying Java process, as it uses its own (stupid) wrapper to address Java.
I'm trying to modify the bin/mule script to have a mode called debug which will pass the above debugger options to the JVM when invoked with:
bin/mule debug
My current work can be found here on PasteBin, and here is the relevant part near line 511:
debug() {
echo "Debugging $APP_LONG_NAME..."
getpid
if [ "X$pid" = "X" ]
then
# The string passed to eval must handle spaces in paths correctly.
COMMAND_LINE="$CMDNICE \"$WRAPPER_CMD\" \"$WRAPPER_CONF\" wrapper.syslog.ident=$APP_NAME wrapper.pidfile=\"$PIDFILE\" $ANCHORPROP $LOCKPROP"
######################################################################
# Customized for Mule
######################################################################
echo "command line: $COMMAND_LINE"
echo "mule opts: $MULE_OPTS"
echo "JPDA_OPTS: $JPDA_OPTS"
eval $COMMAND_LINE $JPDA_OPTS $MULE_OPTS
######################################################################
else
echo "$APP_LONG_NAME is already running."
exit 1
fi
}
I cannot upgrade to a newer version of Mule. I need to find a way to modify this script to simply wait for a debugger when invoked with bin/mule debug. I've modified it enough to get into this debug function I've defined which is basically a copy of their own console function for starting in console mode. I can't seem to figure out how to get my debug opts passed to the JVM. Any ideas?

The parameter -debug, following documentation, was present in 3.4.x:
./mule -debug
Give it a try.

UnsatisfiedLinkError with javaws

I am trying to use android screen cast. http://code.google.com/p/androidscreencast/ All the requirements that is said for installing is there..This is the error I get,
$ javaws androidscreencast.jnlp
$ java.lang.UnsatisfiedLinkError: /usr/lib/jvm/jdk1.6.0/jre/lib/i386/libdeploy.so: libstdc++.so.5: cannot open shared object file: No such file or directory
at java.lang.ClassLoader$NativeLibrary.load(Native Method)
at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1751)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1647)
at java.lang.Runtime.load0(Runtime.java:770)
at java.lang.System.load(System.java:1005)
at com.sun.deploy.config.UnixConfig.loadLibDeploy(UnixConfig.java:38)
at com.sun.deploy.config.UnixConfig.<clinit>(UnixConfig.java:26)
at com.sun.deploy.config.ConfigFactory.newInstance(ConfigFactory.java:11)
at com.sun.deploy.config.Config.getInstance(Config.java:662)
at com.sun.deploy.config.Config.<clinit>(Config.java:678)
at com.sun.javaws.Main.continueInSecureThread(Main.java:119)
at com.sun.javaws.Main$1.run(Main.java:106)
at java.lang.Thread.run(Thread.java:619)
What is the missing file/ path here? what can be done to fix this?

Reason : the Server is not shut Down Properly. Hence this error came.
Solution : Start Task manager look for Javaw.exe with higher value of PID(Process ID) and kill that process and then start the server.
Explanation : If you start task manager and look for javaw.exe you will find 2 processes with this name. One of these process is for Eclipse and other is for Server that is not closed properly. so you need to kill the Servers Javaw.exe process.
To identify this kill the process with high PID value as you can start server only after starting eclipse(unless you are using external tomcat).
Hope this helps..

Java - get PID of external process by command line in Windows 7

I have Windows 7 32 bit with Java:
How do I get the PID of a process by command line in Windows 7?
I want to kill an application which I only can truly identify by the command line which ran it. We have several Java applications running on that machine. I need to stop specific ones.
To be exact: I need to find tomcat which is run by catalina.bat. What do you think is the best way to do this?
I know of tasklist, but it does not seem to be able to query the command line which started the process. Finding java.exe does not help me. I tried searching for something useful like pgrep/pkill for Windows, with no success.

You could use jps -lv command to determine java process by it's command line options. jps is utility that included in many up-to-date JDKs.

Try in a command prompt:
sc queryex type= service state= all | find "APP"
Where APP is the name of the program. This command will return all services that match that.
Then you can run SC QUERYEX APP and it will return the state and PID number.
Once you have the PID:
TASKKILL /f /pid ###
Where ### is the actual PID

Java, get the PID of the current running process in Windows
This should work on Linux, OSX, Windows, and HotSpot JVM's.
import sun.management.VMManagement;
import java.lang.management.ManagementFactory;
import java.lang.management.RuntimeMXBean;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
public static int getCurrentPID() {
try{
java.lang.management.RuntimeMXBean runtime =
java.lang.management.ManagementFactory.getRuntimeMXBean();
java.lang.reflect.Field jvm = runtime.getClass().getDeclaredField("jvm");
jvm.setAccessible(true);
sun.management.VMManagement mgmt =
(sun.management.VMManagement) jvm.get(runtime);
java.lang.reflect.Method pid_method =
mgmt.getClass().getDeclaredMethod("getProcessId");
pid_method.setAccessible(true);
return (Integer) pid_method.invoke(mgmt);
}
catch(Exception e){
e.printStackTrace();
System.out.println("Failed at getting the process ID");
System.exit(0);
}
}
Invoke it like this:
System.out.println("PID: " + getCurrentPID());
For me it prints the processID: PID: 5728
Sources:
How can a Java program get its own process ID?
http://boxysystems.com/index.php/java-tip-find-process-id-of-running-java-process/

If you just need to kill a specific tomcat from a java application why not coding a simple servlet running inside each tomcat that will responde to a get request with a string that will identify it. Then use another servlet to execute something like:
System.exit(-1);

Finally found something. The solution working for me is called wmic (Windows Management Instrumentation Commandline). This nice tool comes built-in to Windows 7 Pro (mine) and possibly other Windows versions. It provides a quite large variety of actions like listing all the running tasks with every details you can imagine (like their corresponding command line), various hardware info, etc. Exactly what I need.