Module PauWareTwo
Package com.pauware.pauware_engine.Core

Class AbstractGuard

java.lang.Object
com.pauware.pauware_engine.Core.AbstractGuard
Direct Known Subclasses:
Guard
public abstract class AbstractGuard
extends java.lang.Object
This abstract class represents the general notion of Guard in UML. Instances of this class are executed at event processing time (notation is: event[guard]/action(s)). It is instantiated within the AbstractStateMachine.fires(String,AbstractState,AbstractState,Object,String,Object[],Object,String,Object[],byte) method. Instances of this class are executed by means of the execute() method during a run-to-completion cycle (AbstractStateMachine.run_to_completion(String,boolean) method).

Compatibility: Java 9.

Since:
1.0

  • Field Summary

    Fields
    Modifier and Type Field Description
    protected AbstractAction _action
    The action to be evaluated.
    protected boolean _value
    The result of the guard's evaluation.

  • Constructor Summary

    Constructors
    Modifier Constructor Description
    protected AbstractGuard​(java.lang.Object guard_object, java.lang.String guard_action, java.lang.Object[] guard_args)
    This constructor is called by the AbstractStateMachine.fires(String,AbstractState,AbstractState,Object,String,Object[],Object,String,Object[],byte) method.

  • Method Summary

    Modifier and Type Method Description
    protected abstract AbstractAction action​(java.lang.Object guard_object, java.lang.String guard_action, java.lang.Object[] guard_args)
    Implementation of this method occurs in Guard.
    boolean equals​(java.lang.Object guard)
    This method is used when a guard object is put in a map data structure as a key.
    protected boolean execute()
    Implementation of this method depends upon the chosen platform, i.e., adaptation for platforms different from Java 9 have to provide specific code.
    int hashCode()
    This method is used when a guard object is put in a map data structure as a key.
    java.lang.String to_UML()
    This method returns the guard in the form of a UML-compliant string.
    protected java.lang.String verbose()
    This method returns the detailed result of the guard's execution.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • _action

      protected AbstractAction _action
      The action to be evaluated. This field is null when no action is associated with a guard. In such a case, the _value field is computed at the beginning of a run-to-completion cycle and frozen during this cycle.

    • _value

      protected boolean _value
      The result of the guard's evaluation. Caution: guards raising exceptions or errors during their evaluation are set to false.

  • Constructor Details

    • AbstractGuard

      protected AbstractGuard​(java.lang.Object guard_object, java.lang.String guard_action, java.lang.Object[] guard_args)
      This constructor is called by the AbstractStateMachine.fires(String,AbstractState,AbstractState,Object,String,Object[],Object,String,Object[],byte) method.
      Parameters:
      guard_object - The object in charge of evaluating the guard; Most of the time, this object is the software component that runs the state machine.
      guard_action - The action to be executed; The execution amounts to evaluating the guard.
      guard_args - The action's arguments.

  • Method Details

    • action

      protected abstract AbstractAction action​(java.lang.Object guard_object, java.lang.String guard_action, java.lang.Object[] guard_args)
      Implementation of this method occurs in Guard.
      Parameters:
      guard_object -
      guard_action -
      guard_args -
      Returns:
      See Also:
      Action

    • equals

      public boolean equals​(java.lang.Object guard)
      This method is used when a guard object is put in a map data structure as a key.
      Overrides:
      equals in class java.lang.Object
      Parameters:
      guard -

    • hashCode

      public int hashCode()
      This method is used when a guard object is put in a map data structure as a key.
      Overrides:
      hashCode in class java.lang.Object

    • execute

      protected boolean execute() throws State_exception
      Implementation of this method depends upon the chosen platform, i.e., adaptation for platforms different from Java 9 have to provide specific code.
      Returns:
      success, failure or false when executed guard does not return a Boolean value.
      Throws:
      State_exception - An encapsulation of any Java problem resulting from evaluating the guard.

    • verbose

      protected java.lang.String verbose()
      This method returns the detailed result of the guard's execution. It calls the AbstractAction.verbose() method if an action is associated with the guard. Otherwise, it returns either false or true.
      Returns:
      The detailed result of the guard's execution as a string.

    • to_UML

      public java.lang.String to_UML()
      This method returns the guard in the form of a UML-compliant string.
      Returns:
      The guard as UML-readable string.