You must add a Finish page to the wizard early in the wizard flow, rather than having the wizard display the Finish button when the Finish page is displayed; the Finish page displays summary information needed from other pages that have not yet been displayed.
To help provide this order of page precedence, there are two helper methods contained in techAdapterWizardPage: addFinishPage() and setFinishPageContents():
addFinishPage() adds a finish page with no contents to the wizard. Most wizards add the Finish page when they remove and add pages
setFinishPageContents(String title, Object contents) calls setFinishPageContents when the user chooses the Next button on the last page of the wizard (from wizardValidatePage() )
The contents of the Finish page can be a Component or a String. If you set the contents of the Finish page to be a String, a MultiLineLabel is created for you.