PortConfig.java revision 12745:f068a4ffddd2
1/* 2 * Copyright (c) 2013, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package sun.net; 27 28import java.security.AccessController; 29 30/** 31 * Determines the ephemeral port range in use on this system. 32 * If this cannot be determined, then the default settings 33 * of the OS are returned. 34 */ 35 36public final class PortConfig { 37 38 private static int defaultUpper, defaultLower; 39 private static final int upper, lower; 40 41 private PortConfig() {} 42 43 static { 44 AccessController.doPrivileged( 45 new java.security.PrivilegedAction<>() { 46 public Void run() { 47 System.loadLibrary("net"); 48 String os = System.getProperty("os.name"); 49 if (os.startsWith("Linux")) { 50 defaultLower = 32768; 51 defaultUpper = 61000; 52 } else if (os.startsWith("SunOS")) { 53 defaultLower = 32768; 54 defaultUpper = 65535; 55 } else if (os.contains("OS X")) { 56 defaultLower = 49152; 57 defaultUpper = 65535; 58 } else if (os.startsWith("AIX")) { 59 // The ephemeral port is OS version dependent on AIX: 60 // http://publib.boulder.ibm.com/infocenter/aix/v7r1/topic/com.ibm.aix.rsct315.admin/bl503_ephport.htm 61 // However, on AIX 5.3 / 6.1 / 7.1 we always see the 62 // settings below by using: 63 // /usr/sbin/no -a | fgrep ephemeral 64 defaultLower = 32768; 65 defaultUpper = 65535; 66 } else { 67 throw new InternalError( 68 "sun.net.PortConfig: unknown OS"); 69 } 70 return null; 71 } 72 }); 73 74 int v = getLower0(); 75 if (v == -1) { 76 v = defaultLower; 77 } 78 lower = v; 79 80 v = getUpper0(); 81 if (v == -1) { 82 v = defaultUpper; 83 } 84 upper = v; 85 } 86 87 static native int getLower0(); 88 static native int getUpper0(); 89 90 public static int getLower() { 91 return lower; 92 } 93 94 public static int getUpper() { 95 return upper; 96 } 97} 98