Package jsl.observers

Class ObservableComponent

  • All Implemented Interfaces:
    ObservableIfc
    public class ObservableComponent
extends java.lang.Object
implements ObservableIfc
    The Java observer/observable pattern has a number of flaws. This class provides a base implementation of the observer/observable pattern that mitigates those flaws. This allows observers to be added and called in the order added to the component. The basic usage of this class is to have a class have an instance of ObservableComponent while implementing the ObservableIfc. The notifyObservers() method can be used to notify attached observers whenever necessary.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void addObserver​(ObserverIfc observer)
      Allows the adding (attaching) of an observer to the observable
      boolean contains​(ObserverIfc observer)
      Returns true if the observer is already attached
      int countObservers()
      Returns how many observers are currently observing the observable
      void deleteObserver​(ObserverIfc observer)
      Allows the deletion (removing) of an observer from the observable
      void deleteObservers()
      Deletes all the observers from the observable
      void notifyObservers​(java.lang.Object theObserved, java.lang.Object arg)
      Notify the observers

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • ObservableComponent

        public ObservableComponent()

    • Method Detail

      • addObserver

        public void addObserver​(ObserverIfc observer)
        Description copied from interface: ObservableIfc
        Allows the adding (attaching) of an observer to the observable
        Specified by:
        addObserver in interface ObservableIfc
        Parameters:
        observer - the observer to attach

      • deleteObserver

        public void deleteObserver​(ObserverIfc observer)
        Description copied from interface: ObservableIfc
        Allows the deletion (removing) of an observer from the observable
        Specified by:
        deleteObserver in interface ObservableIfc
        Parameters:
        observer - the observer to delete

      • contains

        public boolean contains​(ObserverIfc observer)
        Description copied from interface: ObservableIfc
        Returns true if the observer is already attached
        Specified by:
        contains in interface ObservableIfc
        Parameters:
        observer - the observer to check
        Returns:
        true if attached

      • countObservers

        public int countObservers()
        Description copied from interface: ObservableIfc
        Returns how many observers are currently observing the observable
        Specified by:
        countObservers in interface ObservableIfc
        Returns:
        number of observers

      • notifyObservers

        public void notifyObservers​(java.lang.Object theObserved,
                            java.lang.Object arg)
        Notify the observers
        Parameters:
        theObserved -
        arg -