关于struts,forward！

[cultra]

Ideally, whatever globals you use should be defined as String constants to
avoid any misunderstandings or typographical errors. This also makes them available
to the JSPs (but, sadly, not to the XML configuration file). The Jakarta Commons
Scaffold [ASF, Scaffold] package defines several constants for commonly
used globals in its Tokens class:
public static final String CANCEL = "cancel";
public static final String CONTINUE = "continue";
public static final String DONE = "done";
public static final String EMPTY = "empty";
public static final String ERROR = "error";
public static final String EXIT = "exit";
public static final String FORWARD = "forward";
public static final String LOGON = "logon";
public static final String LOGOFF = "logoff";
public static final String MENU = "menu";
public static final String NEXT = "next";
public static final String PREVIOUS = "previous";
public static final String TOKEN = "token";
public static final String WELCOME = "welcome";

这段英语说了什么？能指点一下吗？