org.jgrapht.io.IntegerComponentNameProvider Maven / Gradle / Ivy
/*
* (C) Copyright 2005-2017, by Trevor Harmon and Contributors.
*
* JGraphT : a free Java graph-theory library
*
* This program and the accompanying materials are dual-licensed under
* either
*
* (a) the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation, or (at your option) any
* later version.
*
* or (per the licensee's choosing)
*
* (b) the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation.
*/
package org.jgrapht.io;
import java.util.*;
/**
* Assigns a unique integer to represent each component. Each instance of provider maintains an
* internal map between every component it has ever seen and the unique integer representing that
* edge. As a result it is probably desirable to have a separate instance for each distinct graph.
*
* @param the component type
*
* @author Trevor Harmon
*/
public class IntegerComponentNameProvider
implements
ComponentNameProvider
{
private int nextID = 1;
private final Map idMap = new HashMap<>();
/**
* Clears all cached identifiers, and resets the unique identifier counter.
*/
public void clear()
{
nextID = 1;
idMap.clear();
}
/**
* Returns the string representation of a component.
*
* @param component the component to be named
*/
@Override
public String getName(T component)
{
Integer id = idMap.get(component);
if (id == null) {
id = nextID++;
idMap.put(component, id);
}
return id.toString();
}
}
// End IntegerComponentNameProvider.java