Re: [jgrapht-users] No such vertex in Graph error

[Dimitrios M. <dim...@gm...>]

Almost always this is a problem with hashCode() and Equals() as Joris
suggested.

Some directions for debugging:
 - Make sure that your hashCode() and equals() are consistent.
 - The graph creates edges using an EdgeFactory class. If you do not
provide one by the constructor, it uses a
   ClassBasedEdgeFactory which calls the edge default constructor. If your
edge default constructor does not create unique objects
   then you might experience such problems.
 - The wiki article
https://github.com/jgrapht/jgrapht/wiki/EqualsAndHashCode explains the most
common problems, and
   also describes how to use the class ParanoidGraph for debugging.
 - Try to replace your vertices and edges with Graph<Integer, DefaultEdge>
and see if it works. There are plenty of examples in
   the test cases of the library.


On Mon, Jan 8, 2018 at 12:35 PM, Pallavi Karanth <kar...@gm...>
wrote:

> Changed vertex type to a class which implements equals and hashcode,
> Still getting the same error,
> May I know how to resolve this?
> Thanks much..
>
> On Mon, Jan 8, 2018 at 2:21 PM, J Kinable <j.k...@gm...> wrote:
>
>> Most likely, this is the issue:
>> https://github.com/jgrapht/jgrapht/wiki/EqualsAndHashCode
>>
>>
>> On Mon, Jan 8, 2018 at 1:21 AM, Pallavi Karanth <kar...@gm...
>> > wrote:
>>
>>> Hi,
>>>
>>> Have formed a DefaultDirectedGraph like this:
>>> public DirectedGraph<OWLEntity, DefaultEdge> OWLGraph = new
>>> DefaultDirectedGraph<OWLEntity, DefaultEdge>(DefaultEdge.class);
>>>
>>> Have added vertices and edges,
>>> Vertex list is printed as follows:
>>> System.out.println(OWLGraph.vertexSet());
>>>
>>> The list shows the vertex:
>>> http://www.semanticweb.org/drkm/ontologies/2017/4/untitled-o
>>> ntology-82#Disease
>>>
>>> Am constructing all directed paths from the graph as follows:
>>> AllDirectedPaths allPathsGraph = new AllDirectedPaths(toGraph.OWLGraph);
>>>
>>> Here, OWLGraph is the default directed graph,
>>>
>>> Next, i call getAllPaths from source vertex http://www.semanticweb.
>>> org/drkm/ontologies/2017/4/untitled-ontology-82#Food to destination
>>> vertex:
>>> http://www.semanticweb.org/drkm/ontologies/2017/4/untitled-o
>>> ntology-82#Disease
>>>
>>> The stack trace shows the error as:
>>> java.lang.IllegalArgumentException: no such vertex in graph:
>>> http://www.semanticweb.org/drkm/ontologies/2017/4/unti
>>> tled-ontology-82#Disease
>>> at org.jgrapht.graph.AbstractGraph.assertVertexExist(AbstractGr
>>> aph.java:132)
>>> at org.jgrapht.graph.AbstractBaseGraph.incomingEdgesOf(Abstract
>>> BaseGraph.java:365)
>>> at org.jgrapht.alg.AllDirectedPaths.edgeMinDistancesBackwards(A
>>> llDirectedPaths.java:158)
>>> at org.jgrapht.alg.AllDirectedPaths.getAllPaths(AllDirectedPath
>>> s.java:105)
>>> at org.jgrapht.alg.AllDirectedPaths.getAllPaths(AllDirectedPath
>>> s.java:69)
>>> at com.mycompany.semanticdistance.SemanticDistance.SemanticDist
>>> ance(SemanticDistance.java:161)
>>> at com.mycompany.semanticdistance.SemanticDistance.loadOntology
>>> (SemanticDistance.java:136)
>>> at com.mycompany.semanticdistance.SemanticDistance.main(Semanti
>>> cDistance.java:84)
>>>
>>> May i know how to resolve this?
>>> Kindly help.
>>> Thanks much in advance
>>>
>>> --
>>> Regs, Pallavi
>>>
>>> Linkedin Profile : http://in.linkedin.com/pub/pallavi-karanth/b/b71/26b
>>>
>>> “Your time is limited, don’t waste it living someone else’s life. Don’t
>>> be trapped by dogma, which is living the result of other people’s thinking.
>>> Don’t let the noise of other opinions drown your own inner voice. And most
>>> important, have the courage to follow your heart and intuition, they
>>> somehow already know what you truly want to become. Everything else is
>>> secondary.”
>>>
>>> -- Steve Jobs
>>>
>>> ------------------------------------------------------------
>>> ------------------
>>> Check out the vibrant tech community on one of the world's most
>>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>>> _______________________________________________
>>> jgrapht-users mailing list
>>> jgr...@li...
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>>>
>>>
>>
>
>
> --
> Regs, Pallavi
>
> Linkedin Profile : http://in.linkedin.com/pub/pallavi-karanth/b/b71/26b
>
> “Your time is limited, don’t waste it living someone else’s life. Don’t be
> trapped by dogma, which is living the result of other people’s thinking.
> Don’t let the noise of other opinions drown your own inner voice. And most
> important, have the courage to follow your heart and intuition, they
> somehow already know what you truly want to become. Everything else is
> secondary.”
>
> -- Steve Jobs
>
> ------------------------------------------------------------
> ------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> _______________________________________________
> jgrapht-users mailing list
> jgr...@li...
> https://lists.sourceforge.net/lists/listinfo/jgrapht-users
>
>