Bug 33550 [Dialogs] Dialog should support remembering size and position
There are several dialogs that remember its size and position. Since restore the size and considering screen size and font changes isn't trivial JFace's Dialog class should support remembering and restoring size and position. These would realy ease the task for subclasses. May be you can steel the code from OpenTypeSelectionDialog.
bundles/org.eclipse.ui.ide/extensions/org/eclipse/ui/dialogs/ResourceListSelectionDialog.java
private static final String DIALOG_SETTINGS_SECTION = "ResourceListSelectionDialogSettings"; 
    private static final String DIALOG_ORIGIN_X = "DIALOG_X_ORIGIN"; 
    private static final String DIALOG_ORIGIN_Y = "DIALOG_Y_ORIGIN"; 
    private static final String DIALOG_WIDTH = "DIALOG_WIDTH"; 
    private static final String DIALOG_HEIGHT = "DIALOG_HEIGHT"; 
    
    Text pattern;
    Table resourceNames;