Setting a system.property twice in a same JVM

Question

Hello,
I have got a problem concerning the setting of a system property.
When I run a first time my program I test a case by setting a system property, that works fine.
Now I want to change the same property in the same JVM by doing:
System.setProperties("key","oldvalue");
System.getProperties("key", "oldvalue"); //I obtain oldvalue
System.setProperties("key","newvalue");
System.getProperties("key", "newvalue"); //I obtain newvalueBut apparently it seems the JVM doesn't take the new value of the property even if the getProperty() give me the new value.
So my question is can I change several times the value of a same property in the same JVM or it is technically not possible?
I read the tutorial about System and it says :"The setProperties method changes the set of system properties for the current running application "
Thank you for any assistance

Answer 1

And I say that it apparently does not work because I run some tests
to find why my results were wrong even if in setting a new property.Well, one of those tests might be to just check the changed property right after the change.
Which you do in your code.
And which results in a correctly changed property, doesn't it?
So, what are those other tests you've performed, what was it that you've expected them to do and what did they actually do?
So it is just because if you have initialized the system property once you
cannot do it again or you have to record the new value in a file and then restart
your application by take the value of the system property inside the previously created fileNone of both. You can just change the system properties (just like every other properties) and the changes take place immediately (unless you run multithreaded, in which case you should put the "setproperty" stuff into a synchronized block or method.
Of course, if you try and change the properties of your operating system, then that's different. But I won't start and guess around about what exactly you try to do and what does not work.
Again, try to state plainly
1.) what you programmed, perhaps with some line of code
2.) what you expected your code to do
3.) what happened instead
Provided with that information, forum readers should be able to provide you with some help.
-T-