simple-graph

Simple library for creating different types of graphs and finding the path between two vertices.

Directed and undirected graphs are supported.

Examples

Use your own classes as graph vertices and edges:

Graph<String, Integer> graph = new DirectedGraph<>(Integer.class);   
graph.addVertex("One");
graph.addVertex("Two");
graph.addVertex("Three");
graph.addEdge("One", "Two", 1);
graph.addEdge("Two", "Three", 2);

Or simply use predefined graphs with library default edge entity:

DefaultEdgeGraph<String> graph = new DirectedDefaultEdgeGraph<>();
graph.addVertex("One");
graph.addVertex("Two");
graph.addVertex("Three");
graph.addEdge("One", "Two");
graph.addEdge("Two", "Three");

Please, note! All user-defined vertices and edges classes using for graphs should contain properly implemented hashcode() and equals(Object o) methods - this is critical for stable library work!

Find a possible path between two vertices in a graph:

List<EdgeContainer<String, Integer>> edgeContainers = graph.getPath("One", "Three");

EdgeContainer<V, E> is an edge representation containing two edge vertices (source and target - in case of Directed graphs) and object associated with the edge (Integer instance in the example above).
Current only Breadth-first search algorithm is used under the hood.

Possible future features

1. More clear API for DefaultEdgeGraph<V, E>.
2. Add possibility to use different Graph path search algorithms.
3. Support for graph traverse using user-defined functions for applying it to graph vertices.
4. Support for weighted graphs.
5. Thread-safety.

Inspired by jGrapht - for more complex graph operations it is recommended to use it.