Class Memory

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	/**
15	* Utility functions to report JVM memory usage.
16	*
17	* @author mbdavis
18	*
19	*/
20	public class Memory
21	{
22	public static long used()
23	{
24	Runtime runtime = Runtime.getRuntime ();
25	return runtime.totalMemory() - runtime.freeMemory();
26	}
27
28	public static String usedString()
29	{
30	return format(used());
31	}
32
33	public static long free()
34	{
35	Runtime runtime = Runtime.getRuntime ();
36	return runtime.freeMemory();
37	}
38
39	public static String freeString()
40	{
41	return format(free());
42	}
43
44	public static long total()
45	{
46	Runtime runtime = Runtime.getRuntime ();
47	return runtime.totalMemory();
48	}
49
50	public static String totalString()
51	{
52	return format(total());
53	}
54
55	public static String usedTotalString()
56	{
57	return "Used: " + usedString()
58	+ " Total: " + totalString();
59	}
60
61	public static String allString()
62	{
63	return "Used: " + usedString()
64	+ " Free: " + freeString()
65	+ " Total: " + totalString();
66	}
67
68	public static final double KB = 1024;
69	public static final double MB = 1048576;
70	public static final double GB = 1073741824;
71
72	public static String format(long mem)
73	{
74	if (mem < 2 * KB)
75	return mem + " bytes";
76	if (mem < 2 * MB)
77	return round(mem / KB) + " KB";
78	if (mem < 2 * GB)
79	return round(mem / MB) + " MB";
80	return round(mem / GB) + " GB";
81	}
82
83	public static double round(double d)
84	{
85	return Math.ceil(d * 100) / 100;
86	}
87	}
88