P25 - added parsing of packet payload data for confirmed PDUs.

src/buffer/CircularBuffer.java

@@ -0,0 +1,94 @@
+package buffer;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import sample.Listener;
+
+public class CircularBuffer<T> implements Listener<T>
+{
+	private ArrayList<T> mElements;
+	private Listener<T> mListener;
+	private int mPointer;
+	private int mSize;
+
+
+	/**
+	 * Circular Buffer - stores elements in an array list.  Once the buffer is
+	 * full, new samples replace older samples and older samples are broadcast
+	 * to an optional listener.
+	 * 
+	 * @param size - size of buffer
+	 */
+	public CircularBuffer( int size )
+	{
+		mSize = size;
+		mElements = new ArrayList<T>();
+	}
+
+	/**
+	 * Returns the element stored at index.  Note: the index argument refers to
+	 * the internal storage index and does not indicate a temporal relationship
+	 * among elements.  For example, if you get indexes 1, 2, and 3, you may be
+	 * getting ( oldest - 1, oldest, newest ) elements, if the internal pointer
+	 * is currently pointing to and will insert the next element at index 4.
+	 * 
+	 * @param index - element index
+	 * 
+	 * @return element or null
+	 */
+	public T get( int index )
+	{
+		if( index < mElements.size() )
+		{
+			return mElements.get( index );
+		}
+		
+		return null;
+	}
+	
+	public int getSize()
+	{
+		return mSize;
+	}
+	
+	public List<T> getElements()
+	{
+		return Collections.unmodifiableList( mElements );
+	}
+	
+	@Override
+	public void receive( T element )
+	{
+		T previous = null;
+		
+		if( mElements.size() > mPointer )
+		{
+			previous = mElements.get( mPointer );
+			
+			mElements.set( mPointer, element );
+		}
+		else
+		{
+			mElements.add( element );
+		}
+		
+		mPointer++;
+		
+		if( mPointer >= mSize )
+		{
+			mPointer = 0;
+		}
+		
+		if( previous != null && mListener != null )
+		{
+			mListener.receive( previous );
+		}
+	}
+
+	public void setListener( Listener<T> listener )
+	{
+		mListener = listener;
+	}
+}