Another action mapping in the same namespace (or the default "" namespace) can be executed after this action mapping (see Configuration Files). An optional "namespace" parameter may also be added to specify an action in a different namespace.
One common use of Action chaining is to provide lookup lists (like for a dropdown list of states). Since these Actions get put on the ValueStack, their properties will be available in the view. This functionality can also be done using the ActionTag to execute an Action from the display page. You may also use the Redirect Action Result to accomplish this.
Use with care
Experience shows that chaining should be used with care. If chaining is overused, an application can turn into "spaghetti code". Actions should be treated as a Transaction Script, rather than as methods in a Business Facade. Be sure to ask yourself why you need to chain from one Action to another. Is a navigational issue, or could the logic in Action2 be pushed back to a support class or business facade so that Action1 can call it too?
Ideally, Action classes should be as short as possible. All the core logic should be pushed back to a support class or a business facade, so that Actions only call methods. Actions are best used as adapters, rather than as a class where coding logic is defined.