Bug 300472 [Dialogs] [JFace] Provide accessor for dialog messages
It would be nice to have access to the Dialog messages (eg. IDialogConstants.OK_LABEL) trough API instead of a field access. This would allow the RAP team to provide a session-based translation for the labels and furthermore improves the usability for our current users. Developers who want to single-source their applications for RCP and RAP cannot use the existing API of JFace as the labels are hardcoded as static fields and RAP has no chance to intervene this behavior without breaking API. I suggest to provide an accessor like SWT.getMessage() to get the translated string as this would allow developers to use the same API in RCP and JFace. I'd be happy to provide a patch once we decided on a possible approach. As suggested above, I'd introduce an accessor on Dialog itself and introduce message keys in IDialogConstants.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/IDialogConstants.java
public int BUTTON_MARGIN = 4;
    /**
     * Button height in dialog units (value 14).
     * 
     * @deprecated This constant is no longer in use.
     * The button heights are now determined by the layout.
     */
    public int BUTTON_HEIGHT = 14;
    /**
     * Button width in dialog units (value 61).
     */
    public int BUTTON_WIDTH = 61;
    /**
     * Indent in dialog units (value 21).
     */
    public int INDENT = 21;
    /**
     * Small indent in dialog units (value 7).
     */
    public int SMALL_INDENT = 7;
    /**
     * Entry field width in dialog units (value 200).
     */
    public int ENTRY_FIELD_WIDTH = 200;
    /**
     * Minimum width of message area in dialog units (value 300).
     */
    public int MINIMUM_MESSAGE_AREA_WIDTH = 300;
}