1/*
2 * Copyright (c) 2003, 2004, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24/*
25 *
26 * @bug     4858522
27 * @summary Basic unit test of UnixOperatingSystemMXBean.getMaxFileDescriptorCount()
28 * @author  Steve Bohne
29 */
30
31/*
32 * This test is just a sanity check and does not check for the correct
33 * value.  The correct value should be checked manually:
34 * Solaris/Linux:
35 *   1. In a shell, as user who started java process, enter the command
36 *      "limit -h descriptors"
37 */
38
39import com.sun.management.UnixOperatingSystemMXBean;
40import java.lang.management.*;
41
42public class GetMaxFileDescriptorCount {
43
44    private static UnixOperatingSystemMXBean mbean =
45        (UnixOperatingSystemMXBean)ManagementFactory.getOperatingSystemMXBean();
46
47    // Careful with these values.
48    // Min count for pass dynamically determined below.
49    private static long       min_count_for_pass = 1;
50    private static final long MAX_COUNT_FOR_PASS = Long.MAX_VALUE;
51
52    private static boolean trace = false;
53
54    public static void main(String args[]) throws Exception {
55        if (args.length > 0 && args[0].equals("trace")) {
56            trace = true;
57        }
58
59        long min_count = mbean.getOpenFileDescriptorCount();
60        if (min_count > 0) {
61            min_count_for_pass = min_count;
62        }
63
64        long count = mbean.getMaxFileDescriptorCount();
65
66        if (trace) {
67            System.out.println("Max file descriptor count: " + count);
68        }
69
70        if (count < min_count_for_pass || count > MAX_COUNT_FOR_PASS) {
71            throw new RuntimeException("Max file descriptor count " +
72                                       "illegal value: " + count + " bytes " +
73                                       "(MIN = " + min_count_for_pass + "; " +
74                                       "MAX = " + MAX_COUNT_FOR_PASS + ")");
75        }
76
77        System.out.println("Test passed.");
78    }
79}
80