Bug 29698 drag and drop of java files between packages in package explorer doesn't work
the <preview> <ok> <cancel> dialog shows up, but <ok> has the same effect as <cancel> and <preview> would only show movements of files and no changes in imports of other java files. on <ok> in the preview it only moves the file(s) (as indicated ) without changing referencing imports.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/reorg/JdtMoveAction.java
fQualifiedNameComponent= new QualifiedNameComponent(parent, SWT.NONE, fRefactoring, getRefactoringSettings());
			fQualifiedNameComponent.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
			GridData gd= (GridData)fQualifiedNameComponent.getLayoutData();
			gd.horizontalAlignment= GridData.FILL;
			gd.horizontalIndent= indent;
			fQualifiedNameComponent.setEnabled(false);
			fQualifiedNameCheckbox.addSelectionListener(new SelectionAdapter() {
				public void widgetSelected(SelectionEvent e) {
					boolean enabled= ((Button)e.widget).getSelection();
					fQualifiedNameComponent.setEnabled(enabled);
					fRefactoring.setUpdateQualifiedNames(enabled);
					updateOKStatus();
				}
			});
		}
		
		protected IDialogSettings getRefactoringSettings() {
			IDialogSettings settings= JavaPlugin.getDefault().getDialogSettings();
			if (settings == null)
				return null;
			IDialogSettings result= settings.getSection(RefactoringWizardPage.REFACTORING_SETTINGS);
			if (result == null) {
				result= new DialogSettings(RefactoringWizardPage.REFACTORING_SETTINGS);
				settings.addSection(result); 
			}
			return result;
		}			
	}
}