1 /*
  2  * Copyright (c) 2022, 2026, 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.classfile.impl;
 26 
 27 import java.lang.classfile.AccessFlags;
 28 import java.lang.classfile.ClassFile;
 29 import java.lang.reflect.AccessFlag;
 30 import java.lang.reflect.ClassFileFormatVersion;
 31 import java.util.Set;
 32 
 33 import jdk.internal.misc.VM;
 34 import jdk.internal.reflect.PreviewAccessFlags;
 35 
 36 public final class AccessFlagsImpl extends AbstractElement
 37         implements AccessFlags {
 38 
 39     private final AccessFlag.Location location;
 40     private final int flagsMask;
 41     private final ClassFileFormatVersion formatVersion; // null for preview
 42     private Set<AccessFlag> flags;
 43 
 44     public AccessFlagsImpl(AccessFlag.Location location, AccessFlag... flags) {
 45         this.location = location;
 46         this.flagsMask = Util.flagsToBits(location, flags);
 47         this.flags = Set.of(flags);
 48         this.formatVersion = ClassFileFormatVersion.latest();
 49     }
 50 
 51     public AccessFlagsImpl(AccessFlag.Location location, int mask) {
 52         this(location, mask, ClassFileFormatVersion.latest());
 53     }
 54 
 55     public AccessFlagsImpl(AccessFlag.Location location, int mask, int version) {
 56         int major = version & 0xFFFF;
 57         int minor = version >>> Character.SIZE;
 58 
 59         ClassFileFormatVersion cffv = minor == ClassFile.PREVIEW_MINOR_VERSION
 60                 ? null // Try to guess for older preview features
 61                 : VM.isSupportedClassFileVersion(major, minor) ? ClassFileFormatVersion.fromMajor(major)
 62                                                                : ClassFileFormatVersion.latest(); // Fallback
 63         this(location, mask, cffv);
 64     }
 65 
 66     private AccessFlagsImpl(AccessFlag.Location location, int mask, ClassFileFormatVersion version) {
 67         this.location = location;
 68         this.flagsMask = Util.checkFlags(mask);
 69         this.formatVersion = version;
 70     }
 71 
 72     @Override
 73     public int flagsMask() {
 74         return flagsMask;
 75     }
 76 
 77     @Override
 78     public Set<AccessFlag> flags() {
 79         if (flags == null)
 80             flags = formatVersion == null ? PreviewAccessFlags.maskToAccessFlags(flagsMask, location)
 81                                           : AccessFlag.maskToAccessFlags(flagsMask, location, formatVersion);
 82         return flags;
 83     }
 84 
 85     @Override
 86     public void writeTo(DirectClassBuilder builder) {
 87         builder.setFlags(flagsMask);
 88     }
 89 
 90     @Override
 91     public void writeTo(DirectMethodBuilder builder) {
 92         builder.setFlags(flagsMask);
 93     }
 94 
 95     @Override
 96     public void writeTo(DirectFieldBuilder builder) {
 97         builder.setFlags(flagsMask);
 98     }
 99 
100     @Override
101     public AccessFlag.Location location() {
102         return location;
103     }
104 
105     @Override
106     public boolean has(AccessFlag flag) {
107         return Util.has(location, flagsMask, flag);
108     }
109 
110     @Override
111     public String toString() {
112         return String.format("AccessFlags[flags=%d]", flagsMask);
113     }
114 }