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