An action is a task that a flow processor performs. Actions can occur when a process enters a state, when the process is in the state, and when the process is leaving the state. Actions that occur when a process is entering a state are called entry actions. Actions that occur when a process is leaving a state are called exit actions. It is the state that defines which action occurs and when it occurs. An action has a set of guard conditions that the processor evaluates before it executes the action. The processor checks the guard conditions in the order of appearance in the action's external definition rather than by name.

To support actions, the Automaton provides the Action interface, which, when implemented, may execute a series of steps. These steps may include validating an object or displaying presentation components in a user interface.

The toolkit provides the abstract class DSEAction as a parent class for actions. The toolkit also provides a set of generic actions that you can extend in the com.ibm.dse.automaton.ext package. To extend the behavior of the provided actions, the new classes must implement the execute and preProcess methods. The preProcess method executes before the normal execute method. The generic actions include OpenView, CloseView, and ExecSubflowAct. Additionally, to invoke a process in the business process layer through the EJB or WSIF protocol, the toolkit provides the EJB Access action and the WSIF Access action to use the EJB or WSIF interface.

The toolkit externalizes an action using a tag that has its name defined in the toolkit configuration file. For example, if the tags collection in the file contains the <field id="actionTag1" value="aClass"/> definition, the tag to externalize the action is <actionTag1>.