Package org.apache.jena.graph.impl

Class GraphMatcher

  • public class GraphMatcher
extends java.lang.Object
    An implementation of graph isomorphism for Graph equality. The underlying algorithm is exponential but will only enter a non-deterministic polynomial part when there are a lot of difficult to distinguish anonymous nodes connected to each other by statements with the same property(s). Non-pathological examples, where most nodes have some properties that help distinguish them from other nodes, will experience nearly linear performance.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static boolean equals​(Graph m1, Graph m2)
      Are the two models isomorphic? The isomorphism is defined as a bijection between the anonymous variables such that the statements are identical.
      static int hashCode​(Graph g)  
      static Node[][] match​(Graph m1, Graph m2)
      Return an isomorphism between the two models.

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Method Detail

      • hashCode

        public static int hashCode​(Graph g)

      • match

        public static Node[][] match​(Graph m1,
                             Graph m2)
        Return an isomorphism between the two models. This function is nondeterministic in that it may return a different bijection on each call, in cases where there are multiple isomorphisms between the models.
        Returns:
        null on failure or an array of related pairs (arrays of length 2) of anonymous nodes. match(m1,m2)[i][0] is from m1, and match(m1,m2)[i][1] is the corresponding node in m2.