1/* 2 * Copyright (c) 2006, 2012, 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 */ 25package com.sun.beans.finder; 26 27import static sun.reflect.misc.ReflectUtil.checkPackageAccess; 28 29/** 30 * This is utility class that provides {@code static} methods 31 * to find a class with the specified name using the specified class loader. 32 * 33 * @since 1.7 34 * 35 * @author Sergey A. Malenkov 36 */ 37public final class ClassFinder { 38 39 /** 40 * Returns the {@code Class} object associated 41 * with the class or interface with the given string name, 42 * using the default class loader. 43 * <p> 44 * The {@code name} can denote an array class 45 * (see {@link Class#getName} for details). 46 * 47 * @param name fully qualified name of the desired class 48 * @return class object representing the desired class 49 * 50 * @throws ClassNotFoundException if the class cannot be located 51 * by the specified class loader 52 * 53 * @see Class#forName(String) 54 * @see Class#forName(String,boolean,ClassLoader) 55 * @see ClassLoader#getSystemClassLoader() 56 * @see Thread#getContextClassLoader() 57 */ 58 public static Class<?> findClass(String name) throws ClassNotFoundException { 59 checkPackageAccess(name); 60 try { 61 ClassLoader loader = Thread.currentThread().getContextClassLoader(); 62 if (loader == null) { 63 // can be null in IE (see 6204697) 64 loader = ClassLoader.getSystemClassLoader(); 65 } 66 if (loader != null) { 67 return Class.forName(name, false, loader); 68 } 69 70 } catch (ClassNotFoundException exception) { 71 // use current class loader instead 72 } catch (SecurityException exception) { 73 // use current class loader instead 74 } 75 return Class.forName(name); 76 } 77 78 /** 79 * Returns the {@code Class} object associated with 80 * the class or interface with the given string name, 81 * using the given class loader. 82 * <p> 83 * The {@code name} can denote an array class 84 * (see {@link Class#getName} for details). 85 * <p> 86 * If the parameter {@code loader} is null, 87 * the class is loaded through the default class loader. 88 * 89 * @param name fully qualified name of the desired class 90 * @param loader class loader from which the class must be loaded 91 * @return class object representing the desired class 92 * 93 * @throws ClassNotFoundException if the class cannot be located 94 * by the specified class loader 95 * 96 * @see #findClass(String,ClassLoader) 97 * @see Class#forName(String,boolean,ClassLoader) 98 */ 99 public static Class<?> findClass(String name, ClassLoader loader) throws ClassNotFoundException { 100 checkPackageAccess(name); 101 if (loader != null) { 102 try { 103 return Class.forName(name, false, loader); 104 } catch (ClassNotFoundException exception) { 105 // use default class loader instead 106 } catch (SecurityException exception) { 107 // use default class loader instead 108 } 109 } 110 return findClass(name); 111 } 112 113 /** 114 * Returns the {@code Class} object associated 115 * with the class or interface with the given string name, 116 * using the default class loader. 117 * <p> 118 * The {@code name} can denote an array class 119 * (see {@link Class#getName} for details). 120 * <p> 121 * This method can be used to obtain 122 * any of the {@code Class} objects 123 * representing {@code void} or primitive Java types: 124 * {@code char}, {@code byte}, {@code short}, 125 * {@code int}, {@code long}, {@code float}, 126 * {@code double} and {@code boolean}. 127 * 128 * @param name fully qualified name of the desired class 129 * @return class object representing the desired class 130 * 131 * @throws ClassNotFoundException if the class cannot be located 132 * by the specified class loader 133 * 134 * @see #resolveClass(String,ClassLoader) 135 */ 136 public static Class<?> resolveClass(String name) throws ClassNotFoundException { 137 return resolveClass(name, null); 138 } 139 140 /** 141 * Returns the {@code Class} object associated with 142 * the class or interface with the given string name, 143 * using the given class loader. 144 * <p> 145 * The {@code name} can denote an array class 146 * (see {@link Class#getName} for details). 147 * <p> 148 * If the parameter {@code loader} is null, 149 * the class is loaded through the default class loader. 150 * <p> 151 * This method can be used to obtain 152 * any of the {@code Class} objects 153 * representing {@code void} or primitive Java types: 154 * {@code char}, {@code byte}, {@code short}, 155 * {@code int}, {@code long}, {@code float}, 156 * {@code double} and {@code boolean}. 157 * 158 * @param name fully qualified name of the desired class 159 * @param loader class loader from which the class must be loaded 160 * @return class object representing the desired class 161 * 162 * @throws ClassNotFoundException if the class cannot be located 163 * by the specified class loader 164 * 165 * @see #findClass(String,ClassLoader) 166 * @see PrimitiveTypeMap#getType(String) 167 */ 168 public static Class<?> resolveClass(String name, ClassLoader loader) throws ClassNotFoundException { 169 Class<?> type = PrimitiveTypeMap.getType(name); 170 return (type == null) 171 ? findClass(name, loader) 172 : type; 173 } 174 175 /** 176 * Disable instantiation. 177 */ 178 private ClassFinder() { 179 } 180} 181