content: /*
   * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package openjdk.tools.classfile;
  
  import java.io.IOException;
  import java.util.LinkedHashSet;
  import java.util.Set;
  
  /**
   * See JVMS, sections 4.2, 4.6, 4.7.
   *
   *  <p><b>This is NOT part of any supported API.
   *  If you write code that depends on this, you do so at your own risk.
   *  This code and its internal interfaces are subject to change or
   *  deletion without notice.</b>
   */
  public class AccessFlags {
      public static final int ACC_PUBLIC        = 0x0001; // class, inner, field, method
      public static final int ACC_PRIVATE       = 0x0002; //        inner, field, method
      public static final int ACC_PROTECTED     = 0x0004; //        inner, field, method
      public static final int ACC_STATIC        = 0x0008; //        inner, field, method
      public static final int ACC_FINAL         = 0x0010; // class, inner, field, method
      public static final int ACC_SUPER         = 0x0020; // class
      public static final int ACC_SYNCHRONIZED  = 0x0020; //                      method
      public static final int ACC_VOLATILE      = 0x0040; //               field
      public static final int ACC_BRIDGE        = 0x0040; //                      method
      public static final int ACC_TRANSIENT     = 0x0080; //               field
      public static final int ACC_VARARGS       = 0x0080; //                      method
      public static final int ACC_NATIVE        = 0x0100; //                      method
      public static final int ACC_INTERFACE     = 0x0200; // class, inner
      public static final int ACC_ABSTRACT      = 0x0400; // class, inner,        method
      public static final int ACC_STRICT        = 0x0800; //                      method
      public static final int ACC_SYNTHETIC     = 0x1000; // class, inner, field, method
      public static final int ACC_ANNOTATION    = 0x2000; // class, inner
      public static final int ACC_ENUM          = 0x4000; // class, inner, field
      public static final int ACC_MANDATED      = 0x8000; //                          method parameter
      public static final int ACC_MODULE        = 0x8000; // class
  
      public static enum Kind { Class, InnerClass, Field, Method}
  
      AccessFlags(ClassReader cr) throws IOException {
          this(cr.readUnsignedShort());
      }
  
      public AccessFlags(int flags) {
          this.flags = flags;
      }
  
      public AccessFlags ignore(int mask) {
          return new AccessFlags(flags & ~mask);
      }
  
      public boolean is(int mask) {
          return (flags & mask) != 0;
      }
  
      public int byteLength() {
          return 2;
      }
  
      private static final int[] classModifiers = {
          ACC_PUBLIC, ACC_FINAL, ACC_ABSTRACT
      };
  
      private static final int[] classFlags = {
          ACC_PUBLIC, ACC_FINAL, ACC_SUPER, ACC_INTERFACE, ACC_ABSTRACT,
          ACC_SYNTHETIC, ACC_ANNOTATION, ACC_ENUM, ACC_MODULE
      };
  
      public Set<String> getClassModifiers() {
          int f = ((flags & ACC_INTERFACE) != 0 ? flags & ~ACC_ABSTRACT : flags);
          return getModifiers(f, classModifiers, Kind.Class);
      }
  
      public Set<String> getClassFlags() {
          return getFlags(classFlags, Kind.Class);
      }
  
      private static final int[] innerClassModifiers = {
          ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC, ACC_FINAL,
          ACC_ABSTRACT
      };
  
      private static final int[] innerClassFlags = {
          ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC, ACC_FINAL, ACC_SUPER,
          ACC_INTERFACE, ACC_ABSTRACT, ACC_SYNTHETIC, ACC_ANNOTATION, ACC_ENUM
      };
  
      public Set<String> getInnerClassModifiers() {
          int f = ((flags & ACC_INTERFACE) != 0 ? flags & ~ACC_ABSTRACT : flags);
          return getModifiers(f, innerClassModifiers, Kind.InnerClass);
      }
  
      public Set<String> getInnerClassFlags() {
          return getFlags(innerClassFlags, Kind.InnerClass);
      }
  
      private static final int[] fieldModifiers = {
          ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC, ACC_FINAL,
          ACC_VOLATILE, ACC_TRANSIENT
      };
  
      private static final int[] fieldFlags = {
          ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC, ACC_FINAL,
          ACC_VOLATILE, ACC_TRANSIENT, ACC_SYNTHETIC, ACC_ENUM
      };
  
      public Set<String> getFieldModifiers() {
          return getModifiers(fieldModifiers, Kind.Field);
      }
  
      public Set<String> getFieldFlags() {
          return getFlags(fieldFlags, Kind.Field);
      }
  
      private static final int[] methodModifiers = {
          ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC, ACC_FINAL,
          ACC_SYNCHRONIZED, ACC_NATIVE, ACC_ABSTRACT, ACC_STRICT
      };
  
      private static final int[] methodFlags = {
          ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC, ACC_FINAL,
          ACC_SYNCHRONIZED, ACC_BRIDGE, ACC_VARARGS, ACC_NATIVE, ACC_ABSTRACT,
          ACC_STRICT, ACC_SYNTHETIC
      };
  
      public Set<String> getMethodModifiers() {
          return getModifiers(methodModifiers, Kind.Method);
      }
  
      public Set<String> getMethodFlags() {
          return getFlags(methodFlags, Kind.Method);
      }
  
      private Set<String> getModifiers(int[] modifierFlags, Kind t) {
          return getModifiers(flags, modifierFlags, t);
      }
  
      private static Set<String> getModifiers(int flags, int[] modifierFlags, Kind t) {
          Set<String> s = new LinkedHashSet<>();
          for (int m: modifierFlags) {
              if ((flags & m) != 0)
                  s.add(flagToModifier(m, t));
          }
          return s;
      }
  
      private Set<String> getFlags(int[] expectedFlags, Kind t) {
          Set<String> s = new LinkedHashSet<>();
          int f = flags;
          for (int e: expectedFlags) {
              if ((f & e) != 0) {
                  s.add(flagToName(e, t));
                  f = f & ~e;
              }
          }
          while (f != 0) {
              int bit = Integer.highestOneBit(f);
              s.add("0x" + Integer.toHexString(bit));
              f = f & ~bit;
          }
          return s;
      }
  
      private static String flagToModifier(int flag, Kind t) {
          switch (flag) {
              case ACC_PUBLIC:
                  return "public";
              case ACC_PRIVATE:
                  return "private";
              case ACC_PROTECTED:
                  return "protected";
              case ACC_STATIC:
                  return "static";
              case ACC_FINAL:
                  return "final";
              case ACC_SYNCHRONIZED:
                  return "synchronized";
              case 0x80:
                  return (t == Kind.Field ? "transient" : null);
              case ACC_VOLATILE:
                  return "volatile";
              case ACC_NATIVE:
                  return "native";
              case ACC_ABSTRACT:
                  return "abstract";
              case ACC_STRICT:
                  return "strictfp";
              case ACC_MANDATED:
                  return "mandated";
              default:
                  return null;
          }
      }
  
      private static String flagToName(int flag, Kind t) {
          switch (flag) {
          case ACC_PUBLIC:
              return "ACC_PUBLIC";
          case ACC_PRIVATE:
              return "ACC_PRIVATE";
          case ACC_PROTECTED:
              return "ACC_PROTECTED";
          case ACC_STATIC:
              return "ACC_STATIC";
          case ACC_FINAL:
              return "ACC_FINAL";
          case 0x20:
              return (t == Kind.Class ? "ACC_SUPER" : "ACC_SYNCHRONIZED");
          case 0x40:
              return (t == Kind.Field ? "ACC_VOLATILE" : "ACC_BRIDGE");
          case 0x80:
              return (t == Kind.Field ? "ACC_TRANSIENT" : "ACC_VARARGS");
          case ACC_NATIVE:
              return "ACC_NATIVE";
          case ACC_INTERFACE:
              return "ACC_INTERFACE";
          case ACC_ABSTRACT:
              return "ACC_ABSTRACT";
          case ACC_STRICT:
              return "ACC_STRICT";
          case ACC_SYNTHETIC:
              return "ACC_SYNTHETIC";
          case ACC_ANNOTATION:
              return "ACC_ANNOTATION";
          case ACC_ENUM:
              return "ACC_ENUM";
          case 0x8000:
              return (t == Kind.Class ? "ACC_MODULE" : "ACC_MANDATED");
          default:
              return null;
          }
      }
  
      public final int flags;
  }
  