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      */
  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
  61     public String descriptorString() {
  62         return descriptor;
  63     }
  64 
  65     @Override
  66     public Class<?> resolveConstantDesc(MethodHandles.Lookup lookup) {
  67         return Wrapper.forBasicType(descriptorString().charAt(0)).primitiveType();
  68     }
  69 
  70     @Override
  71     public String toString() {
  72         return String.format("PrimitiveClassDesc[%s]", displayName());
  73     }
  74 }