content: /*
   * Copyright (c) 2008, 2013, 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.javac.code;
  
  import openjdk.tools.javac.util.Assert;
  
  /**
   * Describes the type of program element an extended annotation (or extended
   * compound attribute) targets.
   *
   * By comparison, a Tree.Kind has enum values for all elements in the AST, and
   * it does not provide enough resolution for type arguments (i.e., whether an
   * annotation targets a type argument in a local variable, method return type,
   * or a typecast).
   *
   *  <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>
   */
  // Code duplicated in openjdk.tools.classfile.TypeAnnotation.TargetType
  public enum TargetType {
      /** For annotations on a class type parameter declaration. */
      CLASS_TYPE_PARAMETER(0x00),
  
      /** For annotations on a method type parameter declaration. */
      METHOD_TYPE_PARAMETER(0x01),
  
      /** For annotations on the type of an "extends" or "implements" clause. */
      CLASS_EXTENDS(0x10),
  
      /** For annotations on a bound of a type parameter of a class. */
      CLASS_TYPE_PARAMETER_BOUND(0x11),
  
      /** For annotations on a bound of a type parameter of a method. */
      METHOD_TYPE_PARAMETER_BOUND(0x12),
  
      /** For annotations on a field. */
      FIELD(0x13),
  
      /** For annotations on a method return type. */
      METHOD_RETURN(0x14),
  
      /** For annotations on the method receiver. */
      METHOD_RECEIVER(0x15),
  
      /** For annotations on a method parameter. */
      METHOD_FORMAL_PARAMETER(0x16),
  
      /** For annotations on a throws clause in a method declaration. */
      THROWS(0x17),
  
      /** For annotations on a local variable. */
      LOCAL_VARIABLE(0x40, true),
  
      /** For annotations on a resource variable. */
      RESOURCE_VARIABLE(0x41, true),
  
      /** For annotations on an exception parameter. */
      EXCEPTION_PARAMETER(0x42, true),
  
      /** For annotations on a type test. */
      INSTANCEOF(0x43, true),
  
      /** For annotations on an object creation expression. */
      NEW(0x44, true),
  
      /** For annotations on a constructor reference receiver. */
      CONSTRUCTOR_REFERENCE(0x45, true),
  
      /** For annotations on a method reference receiver. */
      METHOD_REFERENCE(0x46, true),
  
      /** For annotations on a typecast. */
      CAST(0x47, true),
  
      /** For annotations on a type argument of an object creation expression. */
      CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT(0x48, true),
  
      /** For annotations on a type argument of a method call. */
      METHOD_INVOCATION_TYPE_ARGUMENT(0x49, true),
  
      /** For annotations on a type argument of a constructor reference. */
      CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT(0x4A, true),
  
      /** For annotations on a type argument of a method reference. */
      METHOD_REFERENCE_TYPE_ARGUMENT(0x4B, true),
  
      /** For annotations with an unknown target. */
      UNKNOWN(0xFF);
  
      private static final int MAXIMUM_TARGET_TYPE_VALUE = 0x4B;
  
      private final int targetTypeValue;
      private final boolean isLocal;
  
      private TargetType(int targetTypeValue) {
          this(targetTypeValue, false);
      }
  
      private TargetType(int targetTypeValue, boolean isLocal) {
          if (targetTypeValue < 0
                  || targetTypeValue > 255)
                  Assert.error("Attribute type value needs to be an unsigned byte: " + String.format("0x%02X", targetTypeValue));
          this.targetTypeValue = targetTypeValue;
          this.isLocal = isLocal;
      }
  
      /**
       * Returns whether or not this TargetType represents an annotation whose
       * target is exclusively a tree in a method body
       *
       * Note: wildcard bound targets could target a local tree and a class
       * member declaration signature tree
       */
      public boolean isLocal() {
          return isLocal;
      }
  
      public int targetTypeValue() {
          return this.targetTypeValue;
      }
  
      private static final TargetType[] targets;
  
      static {
          targets = new TargetType[MAXIMUM_TARGET_TYPE_VALUE + 1];
          TargetType[] alltargets = values();
          for (TargetType target : alltargets) {
              if (target.targetTypeValue != UNKNOWN.targetTypeValue)
                  targets[target.targetTypeValue] = target;
          }
          for (int i = 0; i <= MAXIMUM_TARGET_TYPE_VALUE; ++i) {
              if (targets[i] == null)
                  targets[i] = UNKNOWN;
          }
      }
  
      public static boolean isValidTargetTypeValue(int tag) {
          if (tag == UNKNOWN.targetTypeValue)
              return true;
  
          return (tag >= 0 && tag < targets.length);
      }
  
      public static TargetType fromTargetTypeValue(int tag) {
          if (tag == UNKNOWN.targetTypeValue)
              return UNKNOWN;
  
          if (tag < 0 || tag >= targets.length)
              Assert.error("Unknown TargetType: " + tag);
          return targets[tag];
      }
  }
  