Currently netbeans allows you to set arguments for a class in the execution 
tab of the class's property sheet, but it does not allow you to 
specify system properties that are to be passed to the class.

Considering that in the Java tutorial, it is recommended that system properties 
be used rather than command line arguments for passing information to a 
program, this enhancement request should be seriously considered.  See:
 
 http://java.sun.com/docs/books/tutorial/essential/attributes/cmdLineArgs.html

The only way you can set system properties in netbeans 3.2 is by cloning an 
executor and adding the "-Dproperty=value" settings in the executors process 
aguments property.

I would like to be able to configure properties on a per class basis.

I have some suggestions:

* Add a "System property tag replace" property (with a default value of "-D" ) 
on the appropriate executor, debugger and compiler types on the expert tab 
(just like there are tag replacement properties on the expert tab of some of 
the compiler types).  The reason I suggest this is that there are some VMs that 
do not use the -D tag for passing system properties (e.g. The Microsoft VM has 
the format "/d:<name>=<value>").

* Add a {systemproperties} tag that can be substituted into the process 
arguments when executing the VM (e.g. like {bootclasspath} ).

* Add a "System properties" property to the execution tab on the properties 
panel for an executable java file (so now there will be both an 'Arguments' 
and 'System properties' properties on the properties panel).