Graphs (Guava: Google Core Libraries for Java 23.0 API)

java.lang.Object
- com.google.common.graph.Graphs

```
@Beta
public final class Graphs
extends Object
```
Static utility methods for Graph, ValueGraph, and Network instances.

Since:

20.0

Author:

James Sexton, Joshua O'Madadhain

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`static <N> MutableGraph<N>`	`copyOf(Graph<N> graph)` Creates a mutable copy of `graph` with the same nodes and edges.
`static <N,E> MutableNetwork<N,E>`	`copyOf(Network<N,E> network)` Creates a mutable copy of `network` with the same nodes and edges.
`static <N,V> MutableValueGraph<N,V>`	`copyOf(ValueGraph<N,V> graph)` Creates a mutable copy of `graph` with the same nodes, edges, and edge values.
`static boolean`	`equivalent(Graph<?> graphA, Graph<?> graphB)` Deprecated. Use `Graph.equals(Object)` instead. This method will be removed in late 2017.
`static boolean`	`equivalent(Network<?,?> networkA, Network<?,?> networkB)` Deprecated. Use `Network.equals(Object)` instead. This method will be removed in late 2017.
`static boolean`	`equivalent(ValueGraph<?,?> graphA, ValueGraph<?,?> graphB)` Deprecated. Use `ValueGraph.equals(Object)` instead. This method will be removed in late 2017.
`static <N> boolean`	`hasCycle(Graph<N> graph)` Returns true if `graph` has at least one cycle.
`static boolean`	`hasCycle(Network<?,?> network)` Returns true if `network` has at least one cycle.
`static <N> MutableGraph<N>`	`inducedSubgraph(Graph<N> graph, Iterable<? extends N> nodes)` Returns the subgraph of `graph` induced by `nodes`.
`static <N,E> MutableNetwork<N,E>`	`inducedSubgraph(Network<N,E> network, Iterable<? extends N> nodes)` Returns the subgraph of `network` induced by `nodes`.
`static <N,V> MutableValueGraph<N,V>`	`inducedSubgraph(ValueGraph<N,V> graph, Iterable<? extends N> nodes)` Returns the subgraph of `graph` induced by `nodes`.
`static <N> Set<N>`	`reachableNodes(Graph<N> graph, N node)` Returns the set of nodes that are reachable from `node`.
`static <N> Graph<N>`	`transitiveClosure(Graph<N> graph)` Returns the transitive closure of `graph`.
`static <N> Graph<N>`	`transpose(Graph<N> graph)` Returns a view of `graph` with the direction (if any) of every edge reversed.
`static <N,E> Network<N,E>`	`transpose(Network<N,E> network)` Returns a view of `network` with the direction (if any) of every edge reversed.
`static <N,V> ValueGraph<N,V>`	`transpose(ValueGraph<N,V> graph)` Returns a view of `graph` with the direction (if any) of every edge reversed.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - hasCycle
```
public static <N> boolean hasCycle(Graph<N> graph)
```
    Returns true if graph has at least one cycle. A cycle is defined as a non-empty subset of edges in a graph arranged to form a path (a sequence of adjacent outgoing edges) starting and ending with the same node.
    This method will detect any non-empty cycle, including self-loops (a cycle of length 1).
  - hasCycle
```
public static boolean hasCycle(Network<?,?> network)
```
    Returns true if network has at least one cycle. A cycle is defined as a non-empty subset of edges in a graph arranged to form a path (a sequence of adjacent outgoing edges) starting and ending with the same node.
    This method will detect any non-empty cycle, including self-loops (a cycle of length 1).
  - transitiveClosure
```
public static <N> Graph<N> transitiveClosure(Graph<N> graph)
```
    Returns the transitive closure of graph. The transitive closure of a graph is another graph with an edge connecting node A to node B if node B is reachable from node A.
    This is a "snapshot" based on the current topology of graph, rather than a live view of the transitive closure of graph. In other words, the returned Graph will not be updated after modifications to graph.
  - reachableNodes
```
public static <N> Set<N> reachableNodes(Graph<N> graph,
                                        N node)
```
    Returns the set of nodes that are reachable from node. Node B is defined as reachable from node A if there exists a path (a sequence of adjacent outgoing edges) starting at node A and ending at node B. Note that a node is always reachable from itself via a zero-length path.
    This is a "snapshot" based on the current topology of graph, rather than a live view of the set of nodes reachable from node. In other words, the returned Set will not be updated after modifications to graph.
    
    Throws:
    
    IllegalArgumentException - if node is not present in graph
  - equivalent
```
@Deprecated
public static boolean equivalent(@Nullable
                                             Graph<?> graphA,
                                             @Nullable
                                             Graph<?> graphB)
```
    Deprecated. Use Graph.equals(Object) instead. This method will be removed in late 2017.
  - equivalent
```
@Deprecated
public static boolean equivalent(@Nullable
                                             ValueGraph<?,?> graphA,
                                             @Nullable
                                             ValueGraph<?,?> graphB)
```
    Deprecated. Use ValueGraph.equals(Object) instead. This method will be removed in late 2017.
  - equivalent
```
@Deprecated
public static boolean equivalent(@Nullable
                                             Network<?,?> networkA,
                                             @Nullable
                                             Network<?,?> networkB)
```
    Deprecated. Use Network.equals(Object) instead. This method will be removed in late 2017.
  - transpose
```
public static <N> Graph<N> transpose(Graph<N> graph)
```
    Returns a view of graph with the direction (if any) of every edge reversed. All other properties remain intact, and further updates to graph will be reflected in the view.
  - transpose
```
public static <N,V> ValueGraph<N,V> transpose(ValueGraph<N,V> graph)
```
    Returns a view of graph with the direction (if any) of every edge reversed. All other properties remain intact, and further updates to graph will be reflected in the view.
  - transpose
```
@GwtIncompatible
public static <N,E> Network<N,E> transpose(Network<N,E> network)
```
    Returns a view of network with the direction (if any) of every edge reversed. All other properties remain intact, and further updates to network will be reflected in the view.
  - inducedSubgraph
```
public static <N> MutableGraph<N> inducedSubgraph(Graph<N> graph,
                                                  Iterable<? extends N> nodes)
```
    Returns the subgraph of graph induced by nodes. This subgraph is a new graph that contains all of the nodes in nodes, and all of the edges from graph for which both nodes are contained by nodes.
    
    Throws:
    
    IllegalArgumentException - if any element in nodes is not a node in the graph
  - inducedSubgraph
```
public static <N,V> MutableValueGraph<N,V> inducedSubgraph(ValueGraph<N,V> graph,
                                                           Iterable<? extends N> nodes)
```
    Returns the subgraph of graph induced by nodes. This subgraph is a new graph that contains all of the nodes in nodes, and all of the edges (and associated edge values) from graph for which both nodes are contained by nodes.
    
    Throws:
    
    IllegalArgumentException - if any element in nodes is not a node in the graph
  - inducedSubgraph
```
@GwtIncompatible
public static <N,E> MutableNetwork<N,E> inducedSubgraph(Network<N,E> network,
                                                                         Iterable<? extends N> nodes)
```
    Returns the subgraph of network induced by nodes. This subgraph is a new graph that contains all of the nodes in nodes, and all of the edges from network for which the incident nodes are both contained by nodes.
    
    Throws:
    
    IllegalArgumentException - if any element in nodes is not a node in the graph
  - copyOf
```
public static <N> MutableGraph<N> copyOf(Graph<N> graph)
```
    Creates a mutable copy of graph with the same nodes and edges.
  - copyOf
```
public static <N,V> MutableValueGraph<N,V> copyOf(ValueGraph<N,V> graph)
```
    Creates a mutable copy of graph with the same nodes, edges, and edge values.
  - copyOf
```
@GwtIncompatible
public static <N,E> MutableNetwork<N,E> copyOf(Network<N,E> network)
```
    Creates a mutable copy of network with the same nodes and edges.

Class Graphs

Method Summary

Methods inherited from class java.lang.Object

Method Detail

hasCycle

hasCycle

transitiveClosure

reachableNodes

equivalent

equivalent

equivalent

transpose

transpose

transpose

inducedSubgraph

inducedSubgraph

inducedSubgraph

copyOf

copyOf

copyOf