[Neo4j] How to create a pipe (User Defined Step), which returns a set of Vertices for each of input Vertex

[skarab77]

I need a pipe, which returns a set of vertices for an input Vertex (wrapped in 
User Defined Step). I use blueprints pipes with Neo4j. My current code is:

import org.junit.Test
import com.tinkerpop.blueprints.pgm.Graph
import com.tinkerpop.blueprints.pgm.Vertex
import com.tinkerpop.blueprints.pgm.impls.neo4j.Neo4jVertex
import com.tinkerpop.blueprints.pgm.impls.tg.TinkerGraphFactory
import com.tinkerpop.gremlin.Gremlin
import com.tinkerpop.pipes.AbstractPipe
import com.tinkerpop.pipes.Pipe

class MyUDSTest  {

public static class MyPipe extends  AbstractPipe<Vertex, Iterable<Vertex>> {

    @Override
    protected Iterable<Vertex> processNextStart() throws NoSuchElementException 
{
            def v =  this.starts.next();

            def nodes = [v, v, v].iterator; 

            return new Iterable<Vertex>() {
            @Override
            public Iterator<Vertex> iterator() {
                return new Iterator<Vertex>() {
                    @Override
                    public boolean hasNext() {
                        return nodes.hasNext();
                    }

                    @Override
                    public Vertex next() {
                        return new Neo4jVertex(nodes.next(), graph);
                    }

                    @Override
                    public void remove() {
                        throw new UnsupportedOperationException();

                    }
                };
            }
        };
}

}

@Test
public void testUDS() 
{           
    Gremlin.load();
    Graph g; 
    Gremlin.defineStep('myPipe',[Vertex,Pipe], { new MyPipe() })

    g = TinkerGraphFactory.createTinkerGraph()
    println "$g"
    def result = [] 
    g.v(1).myPipe.filter{true} >> result

    result.each {
        println "$it"           
    }   

}

}

However it does not work property in the gremlin expression:

Gremlin.defineStep('myPipe',[Vertex,Pipe], { new MyPipe() })
 ...
 def result = [];    
 g.v(1).myPipe >> result

result.each 
{
  println it
}

prints out: neo4j.MyUDSTest$MyPipe$1@49aacd5f. I would expect that I will get a 
list of vertices. Could anybody help me with this pipe? 

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