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