private void searchRecursive()

in src/main/java/org/apache/commons/graph/scc/KosarajuSharirAlgorithm.java [176:220]

• 32 lines of code
• 6 McCabe index (conditional complexity)

    private void searchRecursive( final DirectedGraph<V, E> g, final V source,
                                  final Collection<V> coll, final Set<V> visited,
                                  final boolean forward )
    {
        final LinkedList<V> stack = new LinkedList<V>();
        stack.addLast( source );

        while ( !stack.isEmpty() )
        {
            final V v = stack.removeLast();

            // if the vertex has already been visited it can be put into the
            // collection, as we are now finished expanding this vertex
            // the if takes both cases into account:
            //  * step1: forward && visited.contains(v)
            //  * step2: !forward && !visited.contains(v)
            if ( ! ( forward ^ visited.contains( v ) ) )
            {
                coll.add( v );
                continue;
            }

            // add the current vertex to the stack, so it is visited again
            // when all connected vertices have been visited
            stack.addLast( v );
            if ( forward )
            {
                visited.add( v );
            }
            else
            {
                visited.remove( v );
            }

            // add all not yet visited vertices that can be reached from this
            // vertex to the stack
            for ( V w : g.getOutbound( v ) )
            {
                if ( ! ( forward ^ ! visited.contains( w ) ) )
                {
                    stack.addLast( w );
                }
            }
        }
    }