We can launch Outlook' email by simply using:
Desktop.getDesktop().mail(new java.net.URI("mailto:YourEmailAddress@gmail.com?subject=TEST"));
Is there a similar way to launch an Outlook's new appointment window with some data prefilled? (Not send the new meeting request, just launch the form).
You can use COM from Java under Windows (Jacob) - create an instance of the Outlook.Application object and call CreateItem.
In VB (easy to convert to Java):
set app = CreateObject("Outlook.Application")
set appt = app.CreateItem(1)
appt.Subject = "test appointment"
appt.Body = "Test body"
appt.Start = #08/27/2022#
appt.Display()