public final class Graph<E extends java.lang.Comparable<E>>
extends java.util.AbstractCollection<E>
This implementation supports both the directed graph and the undirected graph concepts from mathematics.
This class is not thread-safe.
| Constructor and Description |
|---|
Graph()
Constructs a new empty
Graph instance. |
Graph(java.util.Collection<E> collection)
Constructs a new
Graph instance given a Collection. |
| Modifier and Type | Method and Description |
|---|---|
boolean |
add(E object)
Adds a vertex for
object if absent. |
boolean |
addDirectedEdge(E from,
E to)
Adds a directed edge from the vertex
from to the vertex to. |
boolean |
addUndirectedEdge(E object0,
E object1)
Adds an undirected edge between the vertices of
object0 and object1. |
java.util.Set<E> |
getIncoming(E object)
Returns the set of vertices that has directed edges pointing to
object. |
java.util.Set<E> |
getOutgoing(E object)
Returns the set of vertices that the vertex of
object has directed edges pointing to. |
java.util.Iterator<E> |
iterator()
Returns an
Iterator over the vertices of this Graph instance. |
int |
size()
Returns the size of this
Graph instance. |
addAll, clear, contains, containsAll, isEmpty, remove, removeAll, retainAll, toArray, toArray, toStringclone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, waitpublic Graph()
Graph instance.public Graph(java.util.Collection<E> collection)
Graph instance given a Collection.
If either collection or any of its elements are null, a NullPointerException will be thrown.
collection - the Collection to addjava.lang.NullPointerException - thrown if, and only if, either collection or any of its elements are nullpublic boolean add(E object)
object if absent.
Returns true if, and only if, a vertex for object was added, false otherwise.
If object is null, a NullPointerException will be thrown.
add in interface java.util.Collection<E extends java.lang.Comparable<E>>add in class java.util.AbstractCollection<E extends java.lang.Comparable<E>>object - the Object to addtrue if, and only if, a vertex for object was added, false otherwisejava.lang.NullPointerException - thrown if, and only if, object is nullpublic boolean addDirectedEdge(E from, E to)
from to the vertex to.
Returns true if, and only if, the edge was added, false otherwise.
If either from or to are null, a NullPointerException will be thrown.
If either from or to has not been added, an IllegalArgumentException will be thrown.
from - the Object of the vertex from which to add a directed edgeto - the Object of the vertex that the directed edge should point totrue if, and only if, the edge was added, false otherwisejava.lang.IllegalArgumentException - thrown if, and only if, either from or to has not been addedjava.lang.NullPointerException - thrown if, and only if, either from or to are nullpublic boolean addUndirectedEdge(E object0, E object1)
object0 and object1.
In this implementation, an undirected edge is represented as two directed edges; one pointing from the vertex of object0 to the vertex of object1 and the other pointing from the vertex of
object1 to the vertex of object0.
Returns true if, and only if, any of the two directed edges were added, false otherwise.
If either object0 or object1 are null, a NullPointerException will be thrown.
If either object0 or object1 has not been added, an IllegalArgumentException will be thrown.
object0 - an Object of a vertexobject1 - an Object of a vertextrue if, and only if, any of the two directed edges were added, false otherwisejava.lang.IllegalArgumentException - thrown if, and only if, either object0 or object1 has not been addedjava.lang.NullPointerException - thrown if, and only if, either object0 or object1 are nullpublic int size()
Graph instance.
The size is determined by how many vertices have been added.
public java.util.Iterator<E> iterator()
Iterator over the vertices of this Graph instance.
The iteration order is determined by the order in which vertices were added.
The Iterator supports removing vertices from this Graph.
iterator in interface java.lang.Iterable<E extends java.lang.Comparable<E>>iterator in interface java.util.Collection<E extends java.lang.Comparable<E>>iterator in class java.util.AbstractCollection<E extends java.lang.Comparable<E>>Iterator over the vertices of this Graph instancepublic java.util.Set<E> getIncoming(E object)
object.
If object is null, a NullPointerException will be thrown.
If object has not been added, an IllegalArgumentException will be thrown.
object - an Object of a vertexobjectjava.lang.IllegalArgumentException - thrown if, and only if, object has not been addedjava.lang.NullPointerException - thrown if, and only if, object is nullpublic java.util.Set<E> getOutgoing(E object)
object has directed edges pointing to.
If object is null, a NullPointerException will be thrown.
If object has not been added, an IllegalArgumentException will be thrown.
object - an Object of a vertexobject has directed edges pointing tojava.lang.IllegalArgumentException - thrown if, and only if, object has not been addedjava.lang.NullPointerException - thrown if, and only if, object is null