com.github.fanavarro.graphlib.SimpleGraphImpl Maven / Gradle / Ivy

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Java library for graph management.
There is a newer version: 0.0.5
package com.github.fanavarro.graphlib;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;

/**
 * Map based graph implementation.
 *
 * @author fabad
 * @param 
 *            the node type
 * @param 
 *            the edge type
 */
public class SimpleGraphImpl extends AbstractGraph {

	/**
	 *
	 */
	private static final long serialVersionUID = 2726268195016138010L;
	/**
	 * The adjacent nodes. Key is a node, value is a map where the key is an
	 * edge and value is a set of nodes connected thought the edge.
	 */
	private Map>> adjacentNodes;

	/**
	 * Instantiates a new simple graph impl.
	 */
	public SimpleGraphImpl() {
		adjacentNodes = new HashMap>>();
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see es.um.dis.graphlib.AbstractGraph#getNodes()
	 */
	@Override
	public Set getNodes() {
		return adjacentNodes.keySet();
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see
	 * es.um.dis.graphlib.AbstractGraph#getAdjacentNodesWithEdges(java.lang.
	 * Object)
	 */
	@Override
	public Map> getAdjacentNodesWithEdges(N node) {
		return adjacentNodes.get(node);
	}

	/**
	 * Adds the node.
	 *
	 * @param node
	 *            the node
	 */
	public void addNode(N node) {
		if (!adjacentNodes.containsKey(node)) {
			adjacentNodes.put(node, new HashMap>());
		}
	}

	/**
	 * Adds the node.
	 *
	 * @param node
	 *            the node
	 * @param edge
	 *            the edge
	 * @param adjacentNode
	 *            the adjacent node
	 */
	public void addNode(N node, E edge, N adjacentNode) {
		if (!adjacentNodes.containsKey(node)) {
			this.addNode(node);
		}
		if (!adjacentNodes.containsKey(adjacentNode)) {
			this.addNode(adjacentNode);
		}
		if (!adjacentNodes.get(node).containsKey(edge)) {
			adjacentNodes.get(node).put(edge, new HashSet());
		}
		adjacentNodes.get(node).get(edge).add(adjacentNode);
	}

	/**
	 * Adds the node.
	 *
	 * @param node
	 *            the node
	 * @param edge
	 *            the edge
	 * @param adjacentNodes
	 *            the adjacent nodes
	 */
	public void addNode(N node, E edge, Set adjacentNodes) {
		for (N adjacentNode : adjacentNodes) {
			this.addNode(node, edge, adjacentNode);
		}
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public boolean equals(final Object other) {
		if (this == other) {
			return true;
		}
		if (!(other instanceof SimpleGraphImpl)) {
			return false;
		}
		SimpleGraphImpl castOther = (SimpleGraphImpl) other;
		return new EqualsBuilder().append(adjacentNodes, castOther.adjacentNodes).isEquals();
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public int hashCode() {
		return new HashCodeBuilder().append(adjacentNodes).toHashCode();
	}

}