Package com.jgalgo.graph

Interface IndexIntIdMap

All Superinterfaces:
IndexIdMap<Integer>
public interface IndexIntIdMap extends IndexIdMap<Integer>
A mapping between IntGraph IDs to IndexGraph indices.

This interface is a specification of IndexIdMap for IntGraph.

A regular graph contains vertices and edges which are identified by a fixed int IDs. An IndexGraph view is provided by the Graph.indexGraph() method, which is a graph in which all methods are accessed with indices rather than fixed IDs. This interface maps between the indices and the fixed IDs of the graph vertices or edges.

Note that the mapping may change during the graph lifetime, as vertices and edges are added and removed from the graph, and a regular graph IDs are fixed, while a index graph indices are always (0,1,2, ...,verticesNum-1) and (0,1,2, ...,edgesNum-1). The mapping object will be updated automatically in such cases.

The mapping interface is used for both vertices and edges, and we use a unify term element in the documentation to describe both of them. If the mapping was obtained by IntGraph.indexGraphVerticesMap() it will map between vertices IDs and indices, and if it was obtained by IntGraph.indexGraphEdgesMap() it will map between edges IDs and indices.

Author:
Barak Ugav
See Also:

  • Method Details

    • indexToIdInt

      int indexToIdInt(int index)
      Get the ID of an element by its index.

      Whether this method maps vertices or edges depends if the mapping object was obtained by IntGraph.indexGraphVerticesMap() or IntGraph.indexGraphEdgesMap().

      Parameters:
      index - an index of an element (vertex/edge)
      Returns:
      the ID of the element
      Throws:
      IndexOutOfBoundsException - if index is not in range [, elementsNum) where elementsNum is the number of either vertices or edges, depending on the context

    • indexToId

      @Deprecated default Integer indexToId(int index)
      Deprecated.
      Please use indexToIdInt(int) instead to avoid un/boxing.
      Get the identifier of an element by its index.

      Whether this method maps vertices or edges depends if the mapping object was obtained by Graph.indexGraphVerticesMap() or Graph.indexGraphEdgesMap().

      Specified by:
      indexToId in interface IndexIdMap<Integer>
      Parameters:
      index - an index of an element (vertex/edge)
      Returns:
      the identifier of the element

    • indexToIdIfExistInt

      int indexToIdIfExistInt(int index)
      Get the identifier of an element by its index if it exists, or -1 if it doesn't.

      Whether this method maps vertices or edges depends if the mapping object was obtained by Graph.indexGraphVerticesMap() or Graph.indexGraphEdgesMap().

      Parameters:
      index - the index of an element (vertex/edge)
      Returns:
      the identifier of the element, or -1 if there is not such element

    • indexToIdIfExist

      @Deprecated default Integer indexToIdIfExist(int index)
      Deprecated.
      Please use indexToIdIfExistInt(int) instead to avoid un/boxing.
      Get the identifier of an element by its index if it exists, or null if it doesn't.

      Whether this method maps vertices or edges depends if the mapping object was obtained by Graph.indexGraphVerticesMap() or Graph.indexGraphEdgesMap().

      Specified by:
      indexToIdIfExist in interface IndexIdMap<Integer>
      Parameters:
      index - the index of an element (vertex/edge)
      Returns:
      the identifier of the element, or null if there is not such element

    • idToIndex

      int idToIndex(int id)
      Get the index of an element by its ID.

      Whether this method maps vertices or edges depends if the mapping object was obtained by IntGraph.indexGraphVerticesMap() or IntGraph.indexGraphEdgesMap().

      Parameters:
      id - an ID of an element (vertex/edge)
      Returns:
      the index of the element
      Throws:
      NoSuchVertexException - if this map maps vertices to ids and id is not a valid identifier of a vertex
      NoSuchEdgeException - if this map maps edges to ids and id is not a valid identifier of an edge

    • idToIndex

      @Deprecated default int idToIndex(Integer id)
      Deprecated.
      Please use idToIndex(int) instead to avoid un/boxing.
      Get the index of an element by its identifier.

      Whether this method maps vertices or edges depends if the mapping object was obtained by Graph.indexGraphVerticesMap() or Graph.indexGraphEdgesMap().

      Specified by:
      idToIndex in interface IndexIdMap<Integer>
      Parameters:
      id - an identifier of an element (vertex/edge)
      Returns:
      the index of the element

    • idToIndexIfExist

      int idToIndexIfExist(int id)
      Get the index of an element by its identifier if it exists, or -1 if it doesn't.

      Whether this method maps vertices or edges depends if the mapping object was obtained by Graph.indexGraphVerticesMap() or Graph.indexGraphEdgesMap().

      Parameters:
      id - an identifier of an element (vertex/edge)
      Returns:
      the index of the element, or -1 if there is not such element

    • idToIndexIfExist

      @Deprecated default int idToIndexIfExist(Integer id)
      Deprecated.
      Please use idToIndexIfExist(int) instead to avoid un/boxing.
      Get the index of an element by its identifier if it exists, or -1 if it doesn't.

      Whether this method maps vertices or edges depends if the mapping object was obtained by Graph.indexGraphVerticesMap() or Graph.indexGraphEdgesMap().

      Specified by:
      idToIndexIfExist in interface IndexIdMap<Integer>
      Parameters:
      id - an identifier of an element (vertex/edge)
      Returns:
      the index of the element, or -1 if there is not such element

    • identityVerticesMap

      static IndexIntIdMap identityVerticesMap(IntSet vertexSet)
      Create an identity mapping between the elements IDs and indices.

      The identity mapping is a mapping in which the ID of an element is equal to its index. This mapping is used by index graphs. The passed set of vertices is expected to be 0,1,2, ..., n-1 where n is the number of vertices in the graph, as only for this set of vertices the identity mapping is possible. The given set is not validated for this condition. The number of vertices, n, is accessible to the mapping by vertexSet.size(), and it is used to determine if an index/id is in range. If the graph is mutable and the mapping should be used during the graph lifetime, the given set should be a view of the graph vertices, so the range checks will be valid.

      Parameters:
      vertexSet - the set of vertices in the graph. The set will be used t
      Returns:
      an identity mapping of the vertices

    • identityEdgesMap

      static IndexIntIdMap identityEdgesMap(IntSet edgeSet)
      Create an identity mapping between the elements IDs and indices.

      The identity mapping is a mapping in which the ID of an element is equal to its index. This mapping is used by index graphs. The passed set of edges is expected to be 0,1,2, ..., m-1 where m is the number of edges in the graph, as only for this set of edges the identity mapping is possible. The given set is not validated for this condition. The number of edges, m, is accessible to the mapping by edgeSet.size(), and it is used to determine if an index/id is in range. If the graph is mutable and the mapping should be used during the graph lifetime, the given set should be a view of the graph edges, so the range checks will be valid.

      Parameters:
      edgeSet - the set of edges in the graph. The set will be used t
      Returns:
      an identity mapping of the edges