Constructor Detail

• CrossComponentIterator

  public CrossComponentIterator​(Graph<V,​E> g,
                                V startVertex)

  Creates a new iterator for the specified graph. Iteration will start at the specified start vertex. If the specified start vertex is null, Iteration will start at an arbitrary graph vertex.

  Parameters:

  g - the graph to be iterated.

  startVertex - the vertex iteration to be started.

  Throws:

  java.lang.IllegalArgumentException - if g==null or does not contain startVertex

Method Detail

• getGraph

  public Graph<V,​E> getGraph()

  Returns:

  the graph being traversed

• hasNext

  public boolean hasNext()

  See Also:

  Iterator.hasNext()

• next

  public V next()

  See Also:

  Iterator.next()

• isConnectedComponentExhausted

  protected abstract boolean isConnectedComponentExhausted()

  Returns true if there are no more uniterated vertices in the currently iterated connected component; false otherwise.

  Returns:

  true if there are no more uniterated vertices in the currently iterated connected component; false otherwise.

• encounterVertex

  protected abstract void encounterVertex​(V vertex,
                                          E edge)

  Update data structures the first time we see a vertex.

  Parameters:

  vertex - the vertex encountered

  edge - the edge via which the vertex was encountered, or null if the vertex is a starting point

• provideNextVertex

  protected abstract V provideNextVertex()

  Returns the vertex to be returned in the following call to the iterator next method.

  Returns:

  the next vertex to be returned by this iterator.

• getSeenData

  protected D getSeenData​(V vertex)

  Access the data stored for a seen vertex.

  Parameters:

  vertex - a vertex which has already been seen.

  Returns:

  data associated with the seen vertex or null if no data was associated with the vertex. A null return can also indicate that the vertex was explicitly associated with null.

• isSeenVertex

  protected boolean isSeenVertex​(java.lang.Object vertex)

  Determines whether a vertex has been seen yet by this traversal.

  Parameters:

  vertex - vertex in question

  Returns:

  true if vertex has already been seen

• encounterVertexAgain

  protected abstract void encounterVertexAgain​(V vertex,
                                               E edge)

  Called whenever we re-encounter a vertex. The default implementation does nothing.

  Parameters:

  vertex - the vertex re-encountered

  edge - the edge via which the vertex was re-encountered

• putSeenData

  protected D putSeenData​(V vertex,
                          D data)

  Stores iterator-dependent data for a vertex that has been seen.

  Parameters:

  vertex - a vertex which has been seen.

  data - data to be associated with the seen vertex.

  Returns:

  previous value associated with specified vertex or null if no data was associated with the vertex. A null return can also indicate that the vertex was explicitly associated with null.

• finishVertex

  protected void finishVertex​(V vertex)

  Called when a vertex has been finished (meaning is dependent on traversal represented by subclass).

  Parameters:

  vertex - vertex which has been finished