EventRequestManager.createModificationWatchpointRequest()
EventRequestManager.createAccessWatchpointRequest()

are not supported by some virtual machines. The queries:

VirtualMachine.canWatchFieldModification()
VirtualMachine.canWatchFieldAccess()

are used to determine if this feature is supported.

In all other places in the JDI API when an unsupported operation
is attempted, java.lang.UnsupportedOperationException is thrown.

The documentation for watchpoint creation must discuss that they
may not be implemented and the exception must be documented and
thrown.

robert.field@Eng 2000-04-11