Passing an entire file to JVM arguments

Question

I have several systems that all need to load the same properties to the JVM. I can use the -D flag to load one property at a time, but i am looking for something that will load all the properties in an entire file at one time. For instance:

I could just add --options-file=blah.properties to all jvms on my network, once, and from then on only change the properties file, which could be a single central file over a network share.

Thank you,

EDIT: Any arguments or commands must also work in a windows environment. Therefore any bash or scripting hacks specific to unix will not work.

Answer 1

That's roughly how we do it:

java $(tr '\n' ' ' < options_file) other args...

Here options_file contains ready -Dsomething or -Xsomething values, one per line. The tr command just replaces every newline with a space.

Answer 2

I don't think you can do that via the command line (without some bash hacks, perhaps), but you definitely can do that programatically:

Simply set one property -DmyPropertiesFile=/your/properties/file.properties and then read that with one of the Properties.load() overloads. After that, System.setProperties(yourProps) should do what you expect.

Of course, this requires that you can hook this code early enough so that your properties will be available when needed (For instance, if the main() method is yours, this is perfect).