Where to find Menu/Toolbar URI constants?

MenuUtil has defined constants that are used to form URI for adding menuitems/toolitems/controls to  eclipse menu/toolbar structure.
org.eclipse.ui.menus.MenuUtil
It also has trim constants that are used to position controls in trim positions on Status/Toolbar.


public final static String WORKBENCH_MENU = "menu:org.eclipse.ui.workbench.menu"; 


    /** Main Menu */
    public final static String MAIN_MENU = "menu:org.eclipse.ui.main.menu";    

 /** Main ToolBar (CoolBar) */
    public final static String MAIN_TOOLBAR = "toolbar:org.eclipse.ui.main.toolbar"; 

    /** -Any- Popup Menu */
    public final static String ANY_POPUP = "popup:org.eclipse.ui.popup.any";

    /** Top Left Trim Area */
    public final static String TRIM_COMMAND1 = "toolbar:org.eclipse.ui.trim.command1"; 

    /** Top Right Trim Area */
    public final static String TRIM_COMMAND2 = "toolbar:org.eclipse.ui.trim.command2"; 


    /** Left Vertical Trim Area */
    public final static String TRIM_VERTICAL1 = "toolbar:org.eclipse.ui.trim.vertical1";
    /** Right Vertical Trim Area */
    public final static String TRIM_VERTICAL2 = "toolbar:org.eclipse.ui.trim.vertical2"; 

    /** Bottom (Status) Trim Area */
    public final static String TRIM_STATUS = "toolbar:org.eclipse.ui.trim.status";