1 /* 2 * Copyright (c) 2018, 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 java.lang.constant; 26 27 import java.lang.invoke.MethodHandles; 28 import java.util.Optional; 29 30 import sun.invoke.util.Wrapper; 31 32 import static java.lang.constant.ConstantDescs.BSM_INVOKE; 33 import static java.lang.constant.ConstantDescs.MHR_CLASSDESC_FACTORY; 34 import static java.util.Objects.requireNonNull; 35 36 /** 37 * A <a href="package-summary.html#nominal">nominal descriptor</a> for the class 38 * constant corresponding to a primitive type (e.g., {@code int.class}). 39 */ 40 final class PrimitiveClassDescImpl 41 extends DynamicConstantDesc<Class<?>> implements ClassDesc { 42 43 private final String descriptor; 44 45 /** 46 * Create a {@linkplain ClassDesc} given a descriptor string for a primitive 47 * type. 48 * 49 * @param descriptor the descriptor string, which must be a one-character 50 * string corresponding to one of the nine base types as per JVMS 4.3 51 * @throws IllegalArgumentException if the descriptor string does not 52 * describe a valid primitive type 53 * @jvms 4.3 Descriptors 54 */ 55 PrimitiveClassDescImpl(String descriptor) { 56 super(ConstantDescs.BSM_PRIMITIVE_CLASS, requireNonNull(descriptor), ConstantDescs.CR_Class); 57 if (descriptor.length() != 1 58 || "VIJCSBFDZ".indexOf(descriptor.charAt(0)) < 0) 59 throw new IllegalArgumentException(String.format("not a valid primitive type descriptor: %s", descriptor)); 60 this.descriptor = descriptor; 61 } 62 63 @Override 64 public String descriptorString() { 65 return descriptor; 66 } 67 68 @Override 69 public Class<?> resolveConstantDesc(MethodHandles.Lookup lookup) { 70 return Wrapper.forBasicType(descriptorString().charAt(0)).primitiveType(); 71 } 72 73 @Override 74 public Optional<? extends ConstantDesc<ConstantDesc<Class<?>>>> describeConstable() { 75 return Optional.of(DynamicConstantDesc.of(BSM_INVOKE, MHR_CLASSDESC_FACTORY, descriptor)); 76 } 77 78 @Override 79 public String toString() { 80 return String.format("PrimitiveClassDesc[%s]", displayName()); 81 } 82 }