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Java > Open Source Codes > org > jsmtpd > generic > ressourceControl > MemControler


1 /*
2  *
3  * Jsmtpd, Java SMTP daemon
4  * Copyright (C) 2005 Jean-Francois POUX, jf.poux@laposte.net
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version 2
9  * of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  *
20  */
21 package org.jsmtpd.generic.ressourceControl;
22
23 import org.apache.commons.logging.Log;
24 import org.apache.commons.logging.LogFactory;
25 import org.jsmtpd.config.ReadConfig;
26
27 /**
28  * Jsmtpd
29  * Wraps info about memory in java
30  * @author Jean-Francois POUX
31  */
32 public class MemControler {
33     private Runtime JavaDoc rt;
34     private Log log = LogFactory.getLog(MemControler.class);
35     private int maxMessageSize = ReadConfig.getInstance().getMaxMessageSize();
36     
37     private MemControler() {
38         rt = Runtime.getRuntime();
39     }
40
41     
42     /**
43      * Give expected message size if known, <0 otherwise
44      */
45     public boolean canAllocate(long messageSize) {
46         
47         long curMessageSize = messageSize>0 ? messageSize : maxMessageSize;
48         
49         long free = rt.freeMemory();
50         long max = rt.maxMemory();
51         long used = max - free;
52
53         long newUsed = used + curMessageSize * 4;
54         if (newUsed>max)
55             return false;
56         
57         return true;
58     }
59
60     public void dump() {
61         long free = rt.freeMemory();
62         long max = rt.maxMemory();
63         long used = max - free;
64         log.debug("free memory " + (float) free / 1048576);
65         log.debug("used memory " + (float) (used) / 1048576);
66         log.debug("max memory " + (float) max / 1048576);
67     }
68
69     public long getMaxMem() {
70         return rt.maxMemory();
71     }
72
73     public long getFreeMem() {
74         return rt.freeMemory();
75     }
76
77     public long getUsedMem() {
78         return rt.maxMemory() - rt.freeMemory();
79     }
80
81 }
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