Class ObjectCounter

1	/*
2	* Copyright (c) 2016 Vivid Solutions.
3	*
4	* All rights reserved. This program and the accompanying materials
5	* are made available under the terms of the Eclipse Public License 2.0
6	* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
7	* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
8	* and the Eclipse Distribution License is available at
9	*
10	* http://www.eclipse.org/org/documents/edl-v10.php.
11	*/
12	package org.locationtech.jts.util;
13
14	import java.util.HashMap;
15	import java.util.Map;
16
17	/**
18	* Counts occurrences of objects.
19	*
20	* @author Martin Davis
21	*
22	*/
23	public class ObjectCounter
24	{
25
26	private Map counts = new HashMap();
27
28	public ObjectCounter() {
29	}
30
31	public void add(Object o)
32	{
33	Counter counter = (Counter) counts.get(o);
34	if (counter == null)
35	counts.put(o, new Counter(1));
36	else
37	counter.increment();
38	}
39
40	// TODO: add remove(Object o)
41
42	public int count(Object o)
43	{
44	Counter counter = (Counter) counts.get(o);
45	if (counter == null)
46	return 0;
47	else
48	return counter.count();
49
50	}
51	private static class Counter
52	{
53	int count = 0;
54
55	public Counter()
56	{
57
58	}
59
60	public Counter(int count)
61	{
62	this.count = count;
63	}
64
65	public int count()
66	{
67	return count;
68	}
69
70	public void increment()
71	{
72	count++;
73	}
74	}
75	}
76