Exiting a MIDlet
The CLDC Specification states that a call to the method
java.lang.System.exit is effectively equivalent to calling the method
Runtime.getRuntime().exit. This means that in a CLDC program, calling
the System.exit method will exit the virtual machine. However, since
MIDP defines its own application model, this behavior is not desirable. For
instance, it is not desirable that a single MIDlet in a MIDlet suite, upon
exiting, would shut down the entire virtual machine (and therefore shut down the
other MIDlets as well.) Rather, a well-behaved MIDlet should exit by calling the
destroyApp and notifyDestroyed methods.
In order to prevent MIDP applications from accidentally
shutting down the entire virtual machine, the MIDP Specification
redefines the behavior of the system.exit method. In MIDP, calling this
method will always throw a java.lang.SecurityException.