A simple lightweight network / graph library written in Java. This is a software library that provides a simple set of tools
to model and analyse data that can be represented as a graph or network. It provides facilities to treat a network
either as directed or undirected using the same simple Network API.
This library hides the implementation details by using the Guice which is a dependency injection framework from Google that allows for code modularity.
There are three basic building blocks in this network API: Network objects, Node objects and Link objects.
To create Network instances we must first initialise our Guice injector.
This entity is resposible for the construction of our library dependency graph.
Injector injector = Guice.createInjector(new NetworkModule());
Network network = injector.getInstance(Network.class);We create an Injector instance from a NetworkModule. This module serves as a Guice configuration, telling
it how to resolve the various dependencies in the network library.
To create a network we simply ask our injector for a instance of the Network.class. The injector
will do the rest and supply an instance from an implementation of Network ready to be used.
The rest is pretty straight forward. The creation of new Node and Link objects is handled by the Network.
Bellow you can see a simple example of how one can create new nodes and links and add them to an existing network
instance.
//create new nodes
Node node1 = network.createNode();
Node node2 = network.createNode();
//add nodes to the network
network.addNode(node1);
network.addNode(node2);
//create a new link
Link link = network.createLink(node1, node2);
//add a new link from node1 to node2
network.addLink(link);
//or
network.addLink(node1,node2);Thats pretty much it. You can now add more nodes, return links between existing nodes, get the neighbours of a given node, etc.
Note: a network instance, is undirected by default. This means that the direction of the links is ignored. If you want to work explicitly with directed or undirected networks you can do it as follows:
//get a directed network
DirectedNetwork network = injector.getInstance(DirectedNetwork.class);
//get an undirected network instance
UndirectedNetwork network = injector.getInstance(UndirectedNetwork.class);
//you can encapsulate both of these in a Network object
Network network = injector.getInstance(DirectedNetwork.class);The DirectedNetwork and UndirectedNetwork interfaces are just tagging interfaces. The methods are exactly the same
as a the Network interface, the instances created like this just behave differently.
A DynamicNetwork works exactly as a normal Network object with the addition of discrete time instances. By default, these network instances are created with a time instance t = 0. You can use all the operations from Network, these will be
associated with this time instance. Whenever you want to model a time change in your DynamicNetwork, you can use the
available operation setCurrentTime(int). If this time instance didn't exist, a deep copy of the previous discrete time instance is created and you can now
work with the network set to the given time. If the time you are switching to already existed, the DynamicNetwork just
alters its state so you can work on it.
An example is given bellow:
Injector injector = Guice.createInjector(new NetworkModule());
DynamicNetwork network = injector.getInstance(DynamicNetwork.class);
//create new nodes at t=0
Node node1 = network.createNode();
Node node2 = network.createNode();
network.setCurrentTime(5);
//create new node at t=5
Node node3 = network.createNode();
Network networkT5 = network;Note that the DynamicNetwork class is a subtype of Network hence you can use encapsulation here.
In the previous example networkT5 contains an instance of a network. As you loose access to the time manipulation
mechanisms, you can only call methods from Network with this object. Moreover, all the alterations on networkT5 are
done for t=5. Also note that if you set the time on the network object, the time on networkT5 is also changed as they
refer the same object.
JNetwork
- Copyright (C) 2013 Davide Nunes
- Authors : Davide Nunes http://davidenunes.com
The JNetwork library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
The JNetwork library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with the JNetwork library.
If not, see GPL 3.0.