Class GraphBuilder<N>

java.lang.Object

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

Type Parameters:

N - The most general node type this builder will support. This is normally Object unless it is constrained by using a method like nodeOrder(com.google.common.graph.ElementOrder<N1>), or the builder is constructed based on an existing Graph using from(Graph).

@Beta
@DoNotMock
public final class GraphBuilder<N>
extends Object

A builder for constructing instances of MutableGraph or ImmutableGraph with user-defined properties.

A Graph built by this class has the following default properties:

• does not allow self-loops
• orders Graph.nodes() in the order in which the elements were added (insertion order)

Graphs built by this class also guarantee that each collection-returning accessor returns a (live) unmodifiable view; see the external documentation for details.

Examples of use:

 // Building a mutable graph
 MutableGraph<String> graph = GraphBuilder.undirected().allowsSelfLoops(true).build();
 graph.putEdge("bread", "bread");
 graph.putEdge("chocolate", "peanut butter");
 graph.putEdge("peanut butter", "jelly");

 // Building an immutable graph
 ImmutableGraph<String> immutableGraph =
     GraphBuilder.undirected()
         .allowsSelfLoops(true)
         .<String>immutable()
         .putEdge("bread", "bread")
         .putEdge("chocolate", "peanut butter")
         .putEdge("peanut butter", "jelly")
         .build();
 

Since:

20.0

Author:

James Sexton, Joshua O'Madadhain

Method Summary

Modifier and Type	Method	Description
GraphBuilder<N>	allowsSelfLoops(boolean allowsSelfLoops)	Specifies whether the graph will allow self-loops (edges that connect a node to itself).
<N1 extends N> MutableGraph<N1>	build()	Returns an empty MutableGraph with the properties of this GraphBuilder.
static GraphBuilder<Object>	directed()	Returns a GraphBuilder for building directed graphs.
GraphBuilder<N>	expectedNodeCount(int expectedNodeCount)	Specifies the expected number of nodes in the graph.
static <N> GraphBuilder<N>	from(Graph<N> graph)	Returns a GraphBuilder initialized with all properties queryable from graph.
<N1 extends N> ImmutableGraph.Builder<N1>	immutable()	Returns an ImmutableGraph.Builder with the properties of this GraphBuilder.
<N1 extends N> GraphBuilder<N1>	incidentEdgeOrder(ElementOrder<N1> incidentEdgeOrder)	Specifies the order of iteration for the elements of Graph.edges(), Graph.adjacentNodes(Object), Graph.predecessors(Object), Graph.successors(Object) and Graph.incidentEdges(Object).
<N1 extends N> GraphBuilder<N1>	nodeOrder(ElementOrder<N1> nodeOrder)	Specifies the order of iteration for the elements of Graph.nodes().
static GraphBuilder<Object>	undirected()	Returns a GraphBuilder for building undirected graphs.

Methods inherited from class java.lang.Object

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

Method Details

directed

public static GraphBuilder<Object> directed()

Returns a GraphBuilder for building directed graphs.

undirected

public static GraphBuilder<Object> undirected()

Returns a GraphBuilder for building undirected graphs.

from

public static <N> GraphBuilder<N> from(Graph<N> graph)

Returns a GraphBuilder initialized with all properties queryable from graph.

The "queryable" properties are those that are exposed through the Graph interface, such as Graph.isDirected(). Other properties, such as expectedNodeCount(int), are not set in the new builder.

immutable

public <N1 extends N> ImmutableGraph.Builder<N1> immutable()

Returns an ImmutableGraph.Builder with the properties of this GraphBuilder.

The returned builder can be used for populating an ImmutableGraph.

Note that the returned builder will always have incidentEdgeOrder(com.google.common.graph.ElementOrder<N1>) set to ElementOrder.stable(), regardless of the value that was set in this builder.

Since:

28.0

allowsSelfLoops

@CanIgnoreReturnValue
public GraphBuilder<N> allowsSelfLoops(boolean allowsSelfLoops)

Specifies whether the graph will allow self-loops (edges that connect a node to itself). Attempting to add a self-loop to a graph that does not allow them will throw an UnsupportedOperationException.

The default value is false.

expectedNodeCount

@CanIgnoreReturnValue
public GraphBuilder<N> expectedNodeCount(int expectedNodeCount)

Specifies the expected number of nodes in the graph.

Throws:

IllegalArgumentException - if expectedNodeCount is negative

nodeOrder

public <N1 extends N> GraphBuilder<N1> nodeOrder(ElementOrder<N1> nodeOrder)

Specifies the order of iteration for the elements of Graph.nodes().

The default value is insertion order.

incidentEdgeOrder

public <N1 extends N> GraphBuilder<N1> incidentEdgeOrder(ElementOrder<N1> incidentEdgeOrder)

Specifies the order of iteration for the elements of Graph.edges(), Graph.adjacentNodes(Object), Graph.predecessors(Object), Graph.successors(Object) and Graph.incidentEdges(Object).

The default value is unordered for mutable graphs. For immutable graphs, this value is ignored; they always have a stable order.

Throws:

IllegalArgumentException - if incidentEdgeOrder is not either ElementOrder.unordered() or ElementOrder.stable().

Since:

29.0

build

public <N1 extends N> MutableGraph<N1> build()

Returns an empty MutableGraph with the properties of this GraphBuilder.