1 /* 2 * Copyright (c) 1999, 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 26 package com.sun.jndi.ldap; 27 28 import java.net.MalformedURLException; 29 import java.net.URL; 30 31 abstract class VersionHelper { 32 33 private static VersionHelper helper = null; 34 35 VersionHelper() {} // Disallow anyone from creating one of these. 36 37 static { 38 try { 39 Class.forName("java.net.URLClassLoader"); // 1.2 test 40 Class.forName("java.security.PrivilegedAction"); // 1.2 test 41 helper = (VersionHelper) 42 Class.forName( 43 "com.sun.jndi.ldap.VersionHelper12").newInstance(); 44 } catch (Exception e) { 45 } 46 47 // Use 1.1 helper if 1.2 test fails, or if we cannot create 1.2 helper 48 if (helper == null) { 49 try { 50 helper = (VersionHelper) 51 Class.forName( 52 "com.sun.jndi.ldap.VersionHelper11").newInstance(); 53 } catch (Exception e) { 54 // should never happen 55 } 56 } 57 } 58 59 static VersionHelper getVersionHelper() { 60 return helper; 61 } 62 63 abstract ClassLoader getURLClassLoader(String[] url) 64 throws MalformedURLException; 65 66 67 static protected URL[] getUrlArray(String[] url) throws MalformedURLException { 68 URL[] urlArray = new URL[url.length]; 69 for (int i = 0; i < urlArray.length; i++) { 70 urlArray[i] = new URL(url[i]); 71 } 72 return urlArray; 73 } 74 75 abstract Class loadClass(String className) throws ClassNotFoundException; 76 77 abstract Thread createThread(Runnable r); 78 }