package cz.cuni.amis.utils.flag;
   
   import java.io.Serializable;
   
   import cz.cuni.amis.utils.flag.Flag.DoInSync;
   
   /**
    * Interface for flags. Flags is a reference that raises events each time the
    * referenced object is changed.
   * <p><p>
   * Note that flag implementation must be {@link Serializable}!
   * 
   * @author ik
   * @author Jimmy
   */
  public interface IFlag<T> extends Serializable {
  
      public void addListener(FlagListener<T> listener);
  
      public void addStrongListener(FlagListener<T> listener);
  
      public void clearListeners();
  
      public T getFlag();
  
      public boolean isListenning(FlagListener<T> listener);
  
      public void removeListener(FlagListener<T> listener);
  
      public void removeAllListeners();
  
      public void setFlag(T newValue);
  
      public ImmutableFlag<T> getImmutable();
  
      public void inSync(DoInSync<T> command);
  
      public boolean isFrozen();
  
      public void freeze();
  
      public void defreeze();
  }