#90 [WIP] on redesigning the channel processing gui components and backing model. Simplifies channel state by introducing a new Metadata class that tracks all metadata for all decoders.

src/channel/state/DecoderState.java

@@ -0,0 +1,228 @@
+package channel.state;
+
+import channel.metadata.Attribute;
+import message.IMessageListener;
+import message.Message;
+import module.Module;
+import module.decode.DecoderType;
+import module.decode.event.ActivitySummaryProvider;
+import module.decode.event.CallEvent;
+import module.decode.event.ICallEventProvider;
+import sample.Broadcaster;
+import sample.Listener;
+import alias.AliasList;
+import audio.metadata.IMetadataProvider;
+import audio.metadata.Metadata;
+
+/**
+ * Channel state monitors the stream of decoded messages produced by the 
+ * decoder and broadcasts call events as they occur within the decoded message activity.
+ * 
+ * Provides access to a textual activity summary of events observed.
+ */
+public abstract class DecoderState extends Module 
+			implements ActivitySummaryProvider,
+					   Listener<Message>,
+					   ICallEventProvider,
+					   IChangedAttributeProvider, 
+					   IDecoderStateEventListener,
+					   IDecoderStateEventProvider,
+					   IMessageListener,
+					   IMetadataProvider
+{
+	/* This has to be a broadcaster in order for references to persist */
+	private Broadcaster<CallEvent> mCallEventBroadcaster = new Broadcaster<>();
+	private Listener<Attribute> mChangedAttributeListener;
+	private Listener<DecoderStateEvent> mDecoderStateListener;
+	private Listener<Metadata> mMetadataListener;
+	
+	private DecoderStateEventListener mDecoderStateEventListener = 
+										new DecoderStateEventListener();
+	
+	protected CallEvent mCurrentCallEvent;
+	
+	private AliasList mAliasList;
+	
+	public DecoderState( AliasList aliasList )
+	{
+		mAliasList = aliasList;
+	}
+	
+	public abstract DecoderType getDecoderType();
+	
+	public AliasList getAliasList()
+	{
+		return mAliasList;
+	}
+	
+	public boolean hasAliasList()
+	{
+		return mAliasList != null;
+	}
+	
+	/**
+	 * Reset the decoder state to prepare for processing a different sample
+	 * source
+	 */
+	public abstract void reset();
+
+	/**
+	 * Allow the decoder to perform any setup actions
+	 */
+	public abstract void init();
+
+	/**
+	 * Implements the IDecoderStateEventListener interface to receive state
+	 * reset events.
+	 */
+	public abstract void receiveDecoderStateEvent( DecoderStateEvent event );
+	
+	/**
+	 * Disposes any resources or pointers held by this instance to prepare for
+	 * garbage collection
+	 */
+	public void dispose()
+	{
+		mCallEventBroadcaster.dispose();
+		mCallEventBroadcaster = null;
+		mChangedAttributeListener = null;
+		mDecoderStateListener = null;
+		mMetadataListener = null;
+
+		mAliasList = null;
+	}
+	
+	/**
+	 * Activity Summary - textual summary of activity observed by the channel state.
+	 */
+	public abstract String getActivitySummary();
+
+	/**
+	 * Broadcasts a call event to any registered listeners
+	 */
+	protected void broadcast( CallEvent event )
+	{
+		mCallEventBroadcaster.broadcast( event );
+	}
+
+	/**
+	 * Adds a call event listener
+	 */
+	@Override
+	public void addCallEventListener( Listener<CallEvent> listener )
+	{
+		mCallEventBroadcaster.addListener( listener );
+	}
+
+	/**
+	 * Removes the call event listener
+	 */
+	@Override
+	public void removeCallEventListener( Listener<CallEvent> listener )
+	{
+		mCallEventBroadcaster.removeListener( listener );
+	}
+
+	@Override
+	public Listener<DecoderStateEvent> getDecoderStateListener()
+	{
+		return mDecoderStateEventListener;
+	}
+	
+	private class DecoderStateEventListener implements Listener<DecoderStateEvent>
+	{
+		@Override
+		public void receive( DecoderStateEvent event )
+		{
+			receiveDecoderStateEvent( event );
+		}
+	}
+	
+	/**
+	 * Broadcasts the channel state attribute change event to all registered
+	 * listeners
+	 */
+	protected void broadcast( Attribute attribute )
+	{
+		if( mChangedAttributeListener != null )
+		{
+			mChangedAttributeListener.receive( attribute );
+		}
+	}
+
+	/**
+	 * Adds the listener to receive channel state attribute change events
+	 */
+	@Override
+	public void setChangedAttributeListener( Listener<Attribute> listener )
+	{
+		mChangedAttributeListener = listener;
+	}
+	
+	/**
+	 * Removes the listener to receive channel state attribute change events
+	 */
+	@Override
+	public void removeChangedAttributeListener()
+	{
+		mChangedAttributeListener = null;
+	}
+
+	/**
+	 * Broadcasts a channel state event to any registered listeners
+	 */
+	protected void broadcast( DecoderStateEvent event )
+	{
+		if( mDecoderStateListener != null )
+		{
+			mDecoderStateListener.receive( event );
+		}
+	}
+
+	/**
+	 * Adds a decoder state event listener
+	 */
+	@Override
+	public void setDecoderStateListener( Listener<DecoderStateEvent> listener )
+	{
+		mDecoderStateListener = listener;
+	}
+
+	/**
+	 * Removes the decoder state event listener
+	 */
+	@Override
+	public void removeDecoderStateListener()
+	{
+		mDecoderStateListener = null;
+	}
+
+	/**
+	 * Broadcasts metadata to a registered listener
+	 */
+	protected void broadcast( Metadata metadata )
+	{
+		if( mMetadataListener != null )
+		{
+			mMetadataListener.receive( metadata );
+		}
+	}
+
+	@Override
+	public void setMetadataListener( Listener<Metadata> listener )
+	{
+		mMetadataListener = listener;
+	}
+
+	@Override
+	public void removeMetadataListener()
+	{
+		mMetadataListener = null;
+	}
+
+	@Override
+	public Listener<Message> getMessageListener()
+	{
+		return this;
+	}
+}