Package com.google.common.graph

Class AbstractBaseGraph<N>

java.lang.Object

com.google.common.graph.AbstractBaseGraph<N>

Type Parameters:

N - Node parameter type

All Implemented Interfaces:

BaseGraph<N>, PredecessorsFunction<N>, SuccessorsFunction<N>

Direct Known Subclasses:

AbstractGraph, AbstractValueGraph

abstract class AbstractBaseGraph<N>
extends java.lang.Object
implements BaseGraph<N>

This class provides a skeletal implementation of BaseGraph.

The methods implemented in this class should not be overridden unless the subclass admits a more efficient implementation.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	AbstractBaseGraph.IncidentEdgeSet<N>

Constructor Summary

Constructors

Constructor	Description
AbstractBaseGraph()

Method Summary

Modifier and Type	Method	Description
int	degree(N node)	Returns the count of node's incident edges, counting self-loops twice (equivalently, the number of times an edge touches node).
protected long	edgeCount()	Returns the number of edges in this graph; used to calculate the size of edges().
java.util.Set<EndpointPair<N>>	edges()	An implementation of BaseGraph.edges() defined in terms of BaseGraph.nodes() and BaseGraph.successors(Object).
boolean	hasEdgeConnecting(EndpointPair<N> endpoints)	Returns true if there is an edge that directly connects endpoints (in the order, if any, specified by endpoints).
boolean	hasEdgeConnecting(N nodeU, N nodeV)	Returns true if there is an edge that directly connects nodeU to nodeV.
java.util.Set<EndpointPair<N>>	incidentEdges(N node)	Returns the edges in this graph whose endpoints include node.
int	inDegree(N node)	Returns the count of node's incoming edges (equal to predecessors(node).size()) in a directed graph.
protected boolean	isOrderingCompatible(EndpointPair<?> endpoints)
int	outDegree(N node)	Returns the count of node's outgoing edges (equal to successors(node).size()) in a directed graph.
protected void	validateEndpoints(EndpointPair<?> endpoints)	Throws IllegalArgumentException if the ordering of endpoints is not compatible with the directionality of this graph.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.google.common.graph.BaseGraph

adjacentNodes, allowsSelfLoops, isDirected, nodeOrder, nodes, predecessors, successors

Constructor Detail

AbstractBaseGraph

AbstractBaseGraph()

Method Detail

edgeCount

protected long edgeCount()

Returns the number of edges in this graph; used to calculate the size of edges(). This implementation requires O(|N|) time. Classes extending this one may manually keep track of the number of edges as the graph is updated, and override this method for better performance.

edges

public java.util.Set<EndpointPair<N>> edges()

An implementation of BaseGraph.edges() defined in terms of BaseGraph.nodes() and BaseGraph.successors(Object).

Specified by:

edges in interface BaseGraph<N>

incidentEdges

public java.util.Set<EndpointPair<N>> incidentEdges(N node)

Description copied from interface: BaseGraph

Returns the edges in this graph whose endpoints include node.

This is equal to the union of incoming and outgoing edges.

Specified by:

incidentEdges in interface BaseGraph<N>

degree

public int degree(N node)

Description copied from interface: BaseGraph

Returns the count of node's incident edges, counting self-loops twice (equivalently, the number of times an edge touches node).

For directed graphs, this is equal to inDegree(node) + outDegree(node).

For undirected graphs, this is equal to incidentEdges(node).size() + (number of self-loops incident to node).

If the count is greater than Integer.MAX_VALUE, returns Integer.MAX_VALUE.

Specified by:

degree in interface BaseGraph<N>

inDegree

public int inDegree(N node)

Description copied from interface: BaseGraph

Returns the count of node's incoming edges (equal to predecessors(node).size()) in a directed graph. In an undirected graph, returns the BaseGraph.degree(Object).

If the count is greater than Integer.MAX_VALUE, returns Integer.MAX_VALUE.

Specified by:

inDegree in interface BaseGraph<N>

outDegree

public int outDegree(N node)

Description copied from interface: BaseGraph

Returns the count of node's outgoing edges (equal to successors(node).size()) in a directed graph. In an undirected graph, returns the BaseGraph.degree(Object).

If the count is greater than Integer.MAX_VALUE, returns Integer.MAX_VALUE.

Specified by:

outDegree in interface BaseGraph<N>

hasEdgeConnecting

public boolean hasEdgeConnecting(N nodeU,
                                 N nodeV)

Description copied from interface: BaseGraph

Returns true if there is an edge that directly connects nodeU to nodeV. This is equivalent to nodes().contains(nodeU) && successors(nodeU).contains(nodeV).

In an undirected graph, this is equal to hasEdgeConnecting(nodeV, nodeU).

Specified by:

hasEdgeConnecting in interface BaseGraph<N>

hasEdgeConnecting

public boolean hasEdgeConnecting(EndpointPair<N> endpoints)

Description copied from interface: BaseGraph

Returns true if there is an edge that directly connects endpoints (in the order, if any, specified by endpoints). This is equivalent to edges().contains(endpoints).

Unlike the other EndpointPair-accepting methods, this method does not throw if the endpoints are unordered; it simply returns false. This is for consistency with the behavior of Collection#contains(Object) (which does not generally throw if the object cannot be present in the collection), and the desire to have this method's behavior be compatible with edges().contains(endpoints).

Specified by:

hasEdgeConnecting in interface BaseGraph<N>

validateEndpoints

protected final void validateEndpoints(EndpointPair<?> endpoints)

Throws IllegalArgumentException if the ordering of endpoints is not compatible with the directionality of this graph.

isOrderingCompatible

protected final boolean isOrderingCompatible(EndpointPair<?> endpoints)