How to set a java system property so that it is effective whenever I start JVM without adding it to the command line arguments

Question

There was a change in Java 1.7 in the way the default Locale is get from the OS. There are methods of restoring the old behaviour e.g. by setting the flag -Dsun.locale.formatasdefault=true when starting a JVM instance.

I would like to set this flag permanently so that I don't have to specify it in command line arguments each time when I start a JVM instance. Is there a file or any other possibility to change the default settings for JVM? Something like the Eclipse.ini file but for the JVM itself?

Underprivileged

I don't believe there is, but you can create a Boot class which automatically executes your program (with the "true" main method in another class), with the desired command line arguments present. – Decorator

Answer 1

You can set set environment variable JAVA_TOOL_OPTIONS in your OS. All Java tools (java, javac, ..) will pick this variable up and use it. So you could e.g. use

SET JAVA_TOOL_OPTIONS=-Dsun.locale.formatasdefault=true

I use this to force a specific locale for each JVM.

But this only works if your application is started through the Java tools. If it is e.g. started from a C program that calls the jvm DLL this won't be used.

Edit: I just tested it, and it seems JAVA_TOOLS_OPTIONS is also picked up when the DLLs are started (verified with a Swing application that uses WinRun4J as a launcher)

See: http://docs.oracle.com/javase/7/docs/webnotes/tsg/TSG-VM/html/envvars.html

Salute

We use _JAVA_OPTIONS and that seems to work for use, don't know if this will work for calling through the DLL though, I doubt it. – Jeep

@MadProgrammer: interesting. I didn't know about _JAVA_OPTIONS – Salute

@a_horse_with_no_name No, I didn't know about it until about a week ago either – Jeep

Information about _JAVA_OPTIONS – Original

Can anyone clear it up for me if I want to add a system property xyz-abc.dest="path", Do I have to prepend it with "-D" ? – Chara