1 /* 2 * Copyright (c) 2016, 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 package jdk.internal.loader; 26 27 import jdk.internal.module.Checks; 28 29 /** 30 * Helper class for Class#getResource, Module#getResourceAsStream, and other 31 * methods that locate a resource in a module. 32 */ 33 public final class ResourceHelper { 34 private ResourceHelper() { } 35 36 /** 37 * Returns the <em>package name</em> for a resource. 38 */ 39 public static String getPackageName(String name) { 40 int index = name.lastIndexOf('/'); 41 if (index != -1) { 42 return name.substring(0, index).replace("/", "."); 43 } else { 44 return ""; 45 } 46 } 47 48 /** 49 * Returns true if the resource is a <em>simple resource</em> that can 50 * never be encapsulated. Resources ending in "{@code .class}" or where 51 * the package name is not a Java identifier are resources that can 52 * never be encapsulated. 53 */ 54 public static boolean isSimpleResource(String name) { 55 int len = name.length(); 56 if (len > 6 && name.endsWith(".class")) { 57 return true; 58 } 59 if (!Checks.isJavaIdentifier(getPackageName(name))) { 60 return true; 61 } 62 return false; 63 } 64 }