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 * Copyright (c) 2003, 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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package sun.reflect.annotation;

import java.lang.annotation.*;
import java.lang.reflect.*;
import java.nio.BufferUnderflowException;
import java.nio.ByteBuffer;
import java.util.*;
import java.util.function.Supplier;
import java.security.AccessController;
import java.security.PrivilegedAction;
import jdk.internal.reflect.ConstantPool;

import sun.reflect.generics.parser.SignatureParser;
import sun.reflect.generics.tree.TypeSignature;
import sun.reflect.generics.factory.GenericsFactory;
import sun.reflect.generics.factory.CoreReflectionFactory;
import sun.reflect.generics.visitor.Reifier;
import sun.reflect.generics.scope.ClassScope;

Parser for Java programming language annotations.  Translates
annotation byte streams emitted by compiler into annotation objects.
Author:
 Josh Bloch
Since:
  1.5/**
 * Parser for Java programming language annotations.  Translates
 * annotation byte streams emitted by compiler into annotation objects.
 *
 * @author  Josh Bloch
 * @since   1.5
 */
public class AnnotationParser {
    
Parses the annotations described by the specified byte array.
resolving constant references in the specified constant pool.
The array must contain an array of annotations as described
in the RuntimeVisibleAnnotations_attribute:
  u2 num_annotations;
  annotation annotations[num_annotations];
Throws:
AnnotationFormatError – if an annotation is found to be
        malformed./**
     * Parses the annotations described by the specified byte array.
     * resolving constant references in the specified constant pool.
     * The array must contain an array of annotations as described
     * in the RuntimeVisibleAnnotations_attribute:
     *
     *   u2 num_annotations;
     *   annotation annotations[num_annotations];
     *
     * @throws AnnotationFormatError if an annotation is found to be
     *         malformed.
     */
    public static Map<Class<? extends Annotation>, Annotation> parseAnnotations(
                byte[] rawAnnotations,
                ConstantPool constPool,
                Class<?> container) {
        if (rawAnnotations == null)
            return Collections.emptyMap();

        try {
            return parseAnnotations2(rawAnnotations, constPool, container, null);
        } catch(BufferUnderflowException e) {
            throw new AnnotationFormatError("Unexpected end of annotations.");
        } catch(IllegalArgumentException e) {
            // Type mismatch in constant pool
            throw new AnnotationFormatError(e);
        }
    }

    
Like parseAnnotations(byte[], ConstantPool, Class) with an additional parameter selectAnnotationClasses which selects the annotation types to parse (other than selected are quickly skipped).
 This method is only used to parse select meta annotations in the construction phase of AnnotationType instances to prevent infinite recursion. 
Params:
selectAnnotationClasses – an array of annotation types to select when parsing/**
     * Like {@link #parseAnnotations(byte[], sun.reflect.ConstantPool, Class)}
     * with an additional parameter {@code selectAnnotationClasses} which selects the
     * annotation types to parse (other than selected are quickly skipped).<p>
     * This method is only used to parse select meta annotations in the construction
     * phase of {@link AnnotationType} instances to prevent infinite recursion.
     *
     * @param selectAnnotationClasses an array of annotation types to select when parsing
     */
    @SafeVarargs
    @SuppressWarnings("varargs") // selectAnnotationClasses is used safely
    static Map<Class<? extends Annotation>, Annotation> parseSelectAnnotations(
                byte[] rawAnnotations,
                ConstantPool constPool,
                Class<?> container,
                Class<? extends Annotation> ... selectAnnotationClasses) {
        if (rawAnnotations == null)
            return Collections.emptyMap();

        try {
            return parseAnnotations2(rawAnnotations, constPool, container, selectAnnotationClasses);
        } catch(BufferUnderflowException e) {
            throw new AnnotationFormatError("Unexpected end of annotations.");
        } catch(IllegalArgumentException e) {
            // Type mismatch in constant pool
            throw new AnnotationFormatError(e);
        }
    }

    private static Map<Class<? extends Annotation>, Annotation> parseAnnotations2(
                byte[] rawAnnotations,
                ConstantPool constPool,
                Class<?> container,
                Class<? extends Annotation>[] selectAnnotationClasses) {
        Map<Class<? extends Annotation>, Annotation> result =
            new LinkedHashMap<Class<? extends Annotation>, Annotation>();
        ByteBuffer buf = ByteBuffer.wrap(rawAnnotations);
        int numAnnotations = buf.getShort() & 0xFFFF;
        for (int i = 0; i < numAnnotations; i++) {
            Annotation a = parseAnnotation2(buf, constPool, container, false, selectAnnotationClasses);
            if (a != null) {
                Class<? extends Annotation> klass = a.annotationType();
                if (AnnotationType.getInstance(klass).retention() == RetentionPolicy.RUNTIME &&
                    result.put(klass, a) != null) {
                        throw new AnnotationFormatError(
                            "Duplicate annotation for class: "+klass+": " + a);
            }
        }
        }
        return result;
    }

    
Parses the parameter annotations described by the specified byte array.
resolving constant references in the specified constant pool.
The array must contain an array of annotations as described
in the RuntimeVisibleParameterAnnotations_attribute:
   u1 num_parameters;
   {
       u2 num_annotations;
       annotation annotations[num_annotations];
   } parameter_annotations[num_parameters];
Unlike parseAnnotations, rawAnnotations must not be null!
A null value must be handled by the caller.  This is so because
we cannot determine the number of parameters if rawAnnotations
is null.  Also, the caller should check that the number
of parameters indicated by the return value of this method
matches the actual number of method parameters.  A mismatch
indicates that an AnnotationFormatError should be thrown.
Throws:
AnnotationFormatError – if an annotation is found to be
        malformed./**
     * Parses the parameter annotations described by the specified byte array.
     * resolving constant references in the specified constant pool.
     * The array must contain an array of annotations as described
     * in the RuntimeVisibleParameterAnnotations_attribute:
     *
     *    u1 num_parameters;
     *    {
     *        u2 num_annotations;
     *        annotation annotations[num_annotations];
     *    } parameter_annotations[num_parameters];
     *
     * Unlike parseAnnotations, rawAnnotations must not be null!
     * A null value must be handled by the caller.  This is so because
     * we cannot determine the number of parameters if rawAnnotations
     * is null.  Also, the caller should check that the number
     * of parameters indicated by the return value of this method
     * matches the actual number of method parameters.  A mismatch
     * indicates that an AnnotationFormatError should be thrown.
     *
     * @throws AnnotationFormatError if an annotation is found to be
     *         malformed.
     */
    public static Annotation[][] parseParameterAnnotations(
                    byte[] rawAnnotations,
                    ConstantPool constPool,
                    Class<?> container) {
        try {
            return parseParameterAnnotations2(rawAnnotations, constPool, container);
        } catch(BufferUnderflowException e) {
            throw new AnnotationFormatError(
                "Unexpected end of parameter annotations.");
        } catch(IllegalArgumentException e) {
            // Type mismatch in constant pool
            throw new AnnotationFormatError(e);
        }
    }

    private static Annotation[][] parseParameterAnnotations2(
                    byte[] rawAnnotations,
                    ConstantPool constPool,
                    Class<?> container) {
        ByteBuffer buf = ByteBuffer.wrap(rawAnnotations);
        int numParameters = buf.get() & 0xFF;
        Annotation[][] result = new Annotation[numParameters][];

        for (int i = 0; i < numParameters; i++) {
            int numAnnotations = buf.getShort() & 0xFFFF;
            List<Annotation> annotations =
                new ArrayList<Annotation>(numAnnotations);
            for (int j = 0; j < numAnnotations; j++) {
                Annotation a = parseAnnotation(buf, constPool, container, false);
                if (a != null) {
                    AnnotationType type = AnnotationType.getInstance(
                                              a.annotationType());
                    if (type.retention() == RetentionPolicy.RUNTIME)
                        annotations.add(a);
                }
            }
            result[i] = annotations.toArray(EMPTY_ANNOTATIONS_ARRAY);
        }
        return result;
    }

    private static final Annotation[] EMPTY_ANNOTATIONS_ARRAY =
                    new Annotation[0];

    
Parses the annotation at the current position in the specified
byte buffer, resolving constant references in the specified constant
pool.  The cursor of the byte buffer must point to an "annotation
structure" as described in the RuntimeVisibleAnnotations_attribute:
annotation {
   u2    type_index;
      u2    num_member_value_pairs;
      {    u2    member_name_index;
            member_value value;
      }    member_value_pairs[num_member_value_pairs];
   }
}
Returns the annotation, or null if the annotation's type cannot
be found by the VM, or is not a valid annotation type.
Params:
exceptionOnMissingAnnotationClass – if true, throw
TypeNotPresentException if a referenced annotation type is not
available at runtime/**
     * Parses the annotation at the current position in the specified
     * byte buffer, resolving constant references in the specified constant
     * pool.  The cursor of the byte buffer must point to an "annotation
     * structure" as described in the RuntimeVisibleAnnotations_attribute:
     *
     * annotation {
     *    u2    type_index;
     *       u2    num_member_value_pairs;
     *       {    u2    member_name_index;
     *             member_value value;
     *       }    member_value_pairs[num_member_value_pairs];
     *    }
     * }
     *
     * Returns the annotation, or null if the annotation's type cannot
     * be found by the VM, or is not a valid annotation type.
     *
     * @param exceptionOnMissingAnnotationClass if true, throw
     * TypeNotPresentException if a referenced annotation type is not
     * available at runtime
     */
    static Annotation parseAnnotation(ByteBuffer buf,
                                              ConstantPool constPool,
                                              Class<?> container,
                                              boolean exceptionOnMissingAnnotationClass) {
       return parseAnnotation2(buf, constPool, container, exceptionOnMissingAnnotationClass, null);
    }

    @SuppressWarnings("unchecked")
    private static Annotation parseAnnotation2(ByteBuffer buf,
                                              ConstantPool constPool,
                                              Class<?> container,
                                              boolean exceptionOnMissingAnnotationClass,
                                              Class<? extends Annotation>[] selectAnnotationClasses) {
        int typeIndex = buf.getShort() & 0xFFFF;
        Class<? extends Annotation> annotationClass = null;
        String sig = "[unknown]";
        try {
            try {
                sig = constPool.getUTF8At(typeIndex);
                annotationClass = (Class<? extends Annotation>)parseSig(sig, container);
            } catch (IllegalArgumentException ex) {
                // support obsolete early jsr175 format class files
                annotationClass = (Class<? extends Annotation>)constPool.getClassAt(typeIndex);
            }
        } catch (NoClassDefFoundError e) {
            if (exceptionOnMissingAnnotationClass)
                // note: at this point sig is "[unknown]" or VM-style
                // name instead of a binary name
                throw new TypeNotPresentException(sig, e);
            skipAnnotation(buf, false);
            return null;
        }
        catch (TypeNotPresentException e) {
            if (exceptionOnMissingAnnotationClass)
                throw e;
            skipAnnotation(buf, false);
            return null;
        }
        if (selectAnnotationClasses != null && !contains(selectAnnotationClasses, annotationClass)) {
            skipAnnotation(buf, false);
            return null;
        }
        AnnotationType type = null;
        try {
            type = AnnotationType.getInstance(annotationClass);
        } catch (IllegalArgumentException e) {
            skipAnnotation(buf, false);
            return null;
        }

        Map<String, Class<?>> memberTypes = type.memberTypes();
        Map<String, Object> memberValues =
            new LinkedHashMap<String, Object>(type.memberDefaults());

        int numMembers = buf.getShort() & 0xFFFF;
        for (int i = 0; i < numMembers; i++) {
            int memberNameIndex = buf.getShort() & 0xFFFF;
            String memberName = constPool.getUTF8At(memberNameIndex);
            Class<?> memberType = memberTypes.get(memberName);

            if (memberType == null) {
                // Member is no longer present in annotation type; ignore it
                skipMemberValue(buf);
            } else {
                Object value = parseMemberValue(memberType, buf, constPool, container);
                if (value instanceof AnnotationTypeMismatchExceptionProxy)
                    ((AnnotationTypeMismatchExceptionProxy) value).
                        setMember(type.members().get(memberName));
                memberValues.put(memberName, value);
            }
        }
        return annotationForMap(annotationClass, memberValues);
    }

    
Returns an annotation of the given type backed by the given member -> value map. /**
     * Returns an annotation of the given type backed by the given
     * member {@literal ->} value map.
     */
    public static Annotation annotationForMap(final Class<? extends Annotation> type,
                                              final Map<String, Object> memberValues)
    {
        return AccessController.doPrivileged(new PrivilegedAction<Annotation>() {
            public Annotation run() {
                return (Annotation) Proxy.newProxyInstance(
                    type.getClassLoader(), new Class<?>[] { type },
                    new AnnotationInvocationHandler(type, memberValues));
            }});
    }

    
Parses the annotation member value at the current position in the
specified byte buffer, resolving constant references in the specified
constant pool.  The cursor of the byte buffer must point to a
"member_value structure" as described in the
RuntimeVisibleAnnotations_attribute:
 member_value {
   u1 tag;
   union {
      u2   const_value_index;
      {
          u2   type_name_index;
          u2   const_name_index;
      } enum_const_value;
      u2   class_info_index;
      annotation annotation_value;
      {
          u2    num_values;
          member_value values[num_values];
      } array_value;
   } value;
}
The member must be of the indicated type. If it is not, this
method returns an AnnotationTypeMismatchExceptionProxy.
/**
     * Parses the annotation member value at the current position in the
     * specified byte buffer, resolving constant references in the specified
     * constant pool.  The cursor of the byte buffer must point to a
     * "member_value structure" as described in the
     * RuntimeVisibleAnnotations_attribute:
     *
     *  member_value {
     *    u1 tag;
     *    union {
     *       u2   const_value_index;
     *       {
     *           u2   type_name_index;
     *           u2   const_name_index;
     *       } enum_const_value;
     *       u2   class_info_index;
     *       annotation annotation_value;
     *       {
     *           u2    num_values;
     *           member_value values[num_values];
     *       } array_value;
     *    } value;
     * }
     *
     * The member must be of the indicated type. If it is not, this
     * method returns an AnnotationTypeMismatchExceptionProxy.
     */
    @SuppressWarnings("unchecked")
    public static Object parseMemberValue(Class<?> memberType,
                                          ByteBuffer buf,
                                          ConstantPool constPool,
                                          Class<?> container) {
        Object result = null;
        int tag = buf.get();
        switch(tag) {
          case 'e':
              return parseEnumValue((Class<? extends Enum<?>>)memberType, buf, constPool, container);
          case 'c':
              result = parseClassValue(buf, constPool, container);
              break;
          case '@':
              result = parseAnnotation(buf, constPool, container, true);
              break;
          case '[':
              return parseArray(memberType, buf, constPool, container);
          default:
              result = parseConst(tag, buf, constPool);
        }

        if (!(result instanceof ExceptionProxy) &&
            !memberType.isInstance(result))
            result = new AnnotationTypeMismatchExceptionProxy(
                result.getClass() + "[" + result + "]");
        return result;
    }

    
Parses the primitive or String annotation member value indicated by
the specified tag byte at the current position in the specified byte
buffer, resolving constant reference in the specified constant pool.
The cursor of the byte buffer must point to an annotation member value
of the type indicated by the specified tag, as described in the
RuntimeVisibleAnnotations_attribute:
      u2   const_value_index;
/**
     * Parses the primitive or String annotation member value indicated by
     * the specified tag byte at the current position in the specified byte
     * buffer, resolving constant reference in the specified constant pool.
     * The cursor of the byte buffer must point to an annotation member value
     * of the type indicated by the specified tag, as described in the
     * RuntimeVisibleAnnotations_attribute:
     *
     *       u2   const_value_index;
     */
    private static Object parseConst(int tag,
                                     ByteBuffer buf, ConstantPool constPool) {
        int constIndex = buf.getShort() & 0xFFFF;
        switch(tag) {
          case 'B':
            return Byte.valueOf((byte) constPool.getIntAt(constIndex));
          case 'C':
            return Character.valueOf((char) constPool.getIntAt(constIndex));
          case 'D':
            return Double.valueOf(constPool.getDoubleAt(constIndex));
          case 'F':
            return Float.valueOf(constPool.getFloatAt(constIndex));
          case 'I':
            return Integer.valueOf(constPool.getIntAt(constIndex));
          case 'J':
            return Long.valueOf(constPool.getLongAt(constIndex));
          case 'S':
            return Short.valueOf((short) constPool.getIntAt(constIndex));
          case 'Z':
            return Boolean.valueOf(constPool.getIntAt(constIndex) != 0);
          case 's':
            return constPool.getUTF8At(constIndex);
          default:
            throw new AnnotationFormatError(
                "Invalid member-value tag in annotation: " + tag);
        }
    }

    
Parses the Class member value at the current position in the
specified byte buffer, resolving constant references in the specified
constant pool.  The cursor of the byte buffer must point to a "class
info index" as described in the RuntimeVisibleAnnotations_attribute:
      u2   class_info_index;
/**
     * Parses the Class member value at the current position in the
     * specified byte buffer, resolving constant references in the specified
     * constant pool.  The cursor of the byte buffer must point to a "class
     * info index" as described in the RuntimeVisibleAnnotations_attribute:
     *
     *       u2   class_info_index;
     */
    private static Object parseClassValue(ByteBuffer buf,
                                          ConstantPool constPool,
                                          Class<?> container) {
        int classIndex = buf.getShort() & 0xFFFF;
        try {
            try {
                String sig = constPool.getUTF8At(classIndex);
                return parseSig(sig, container);
            } catch (IllegalArgumentException ex) {
                // support obsolete early jsr175 format class files
                return constPool.getClassAt(classIndex);
            }
        } catch (NoClassDefFoundError e) {
            return new TypeNotPresentExceptionProxy("[unknown]", e);
        }
        catch (TypeNotPresentException e) {
            return new TypeNotPresentExceptionProxy(e.typeName(), e.getCause());
        }
    }

    private static Class<?> parseSig(String sig, Class<?> container) {
        if (sig.equals("V")) return void.class;
        SignatureParser parser = SignatureParser.make();
        TypeSignature typeSig = parser.parseTypeSig(sig);
        GenericsFactory factory = CoreReflectionFactory.make(container, ClassScope.make(container));
        Reifier reify = Reifier.make(factory);
        typeSig.accept(reify);
        Type result = reify.getResult();
        return toClass(result);
    }
    static Class<?> toClass(Type o) {
        if (o instanceof GenericArrayType)
            return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
                                     0)
                .getClass();
        return (Class)o;
    }

    
Parses the enum constant member value at the current position in the
specified byte buffer, resolving constant references in the specified
constant pool.  The cursor of the byte buffer must point to a
"enum_const_value structure" as described in the
RuntimeVisibleAnnotations_attribute:
      {
          u2   type_name_index;
          u2   const_name_index;
      } enum_const_value;
/**
     * Parses the enum constant member value at the current position in the
     * specified byte buffer, resolving constant references in the specified
     * constant pool.  The cursor of the byte buffer must point to a
     * "enum_const_value structure" as described in the
     * RuntimeVisibleAnnotations_attribute:
     *
     *       {
     *           u2   type_name_index;
     *           u2   const_name_index;
     *       } enum_const_value;
     */
    @SuppressWarnings({"rawtypes", "unchecked"})
    private static Object parseEnumValue(Class<? extends Enum> enumType, ByteBuffer buf,
                                         ConstantPool constPool,
                                         Class<?> container) {
        int typeNameIndex = buf.getShort() & 0xFFFF;
        String typeName  = constPool.getUTF8At(typeNameIndex);
        int constNameIndex = buf.getShort() & 0xFFFF;
        String constName = constPool.getUTF8At(constNameIndex);

        if (!typeName.endsWith(";")) {
            // support now-obsolete early jsr175-format class files.
            if (!enumType.getName().equals(typeName))
            return new AnnotationTypeMismatchExceptionProxy(
                typeName + "." + constName);
        } else if (enumType != parseSig(typeName, container)) {
            return new AnnotationTypeMismatchExceptionProxy(
                typeName + "." + constName);
        }

        try {
            return  Enum.valueOf(enumType, constName);
        } catch(IllegalArgumentException e) {
            return new EnumConstantNotPresentExceptionProxy(
                (Class<? extends Enum<?>>)enumType, constName);
        }
    }

    
Parses the array value at the current position in the specified byte
buffer, resolving constant references in the specified constant pool.
The cursor of the byte buffer must point to an array value struct
as specified in the RuntimeVisibleAnnotations_attribute:
      {
          u2    num_values;
          member_value values[num_values];
      } array_value;
If the array values do not match arrayType, an
AnnotationTypeMismatchExceptionProxy will be returned.
/**
     * Parses the array value at the current position in the specified byte
     * buffer, resolving constant references in the specified constant pool.
     * The cursor of the byte buffer must point to an array value struct
     * as specified in the RuntimeVisibleAnnotations_attribute:
     *
     *       {
     *           u2    num_values;
     *           member_value values[num_values];
     *       } array_value;
     *
     * If the array values do not match arrayType, an
     * AnnotationTypeMismatchExceptionProxy will be returned.
     */
    @SuppressWarnings("unchecked")
    private static Object parseArray(Class<?> arrayType,
                                     ByteBuffer buf,
                                     ConstantPool constPool,
                                     Class<?> container) {
        int length = buf.getShort() & 0xFFFF;  // Number of array components
        Class<?> componentType = arrayType.getComponentType();

        if (componentType == byte.class) {
            return parseByteArray(length, buf, constPool);
        } else if (componentType == char.class) {
            return parseCharArray(length, buf, constPool);
        } else if (componentType == double.class) {
            return parseDoubleArray(length, buf, constPool);
        } else if (componentType == float.class) {
            return parseFloatArray(length, buf, constPool);
        } else if (componentType == int.class) {
            return parseIntArray(length, buf, constPool);
        } else if (componentType == long.class) {
            return parseLongArray(length, buf, constPool);
        } else if (componentType == short.class) {
            return parseShortArray(length, buf, constPool);
        } else if (componentType == boolean.class) {
            return parseBooleanArray(length, buf, constPool);
        } else if (componentType == String.class) {
            return parseStringArray(length, buf, constPool);
        } else if (componentType == Class.class) {
            return parseClassArray(length, buf, constPool, container);
        } else if (componentType.isEnum()) {
            return parseEnumArray(length, (Class<? extends Enum<?>>)componentType, buf,
                                  constPool, container);
        } else {
            assert componentType.isAnnotation();
            return parseAnnotationArray(length, (Class <? extends Annotation>)componentType, buf,
                                        constPool, container);
        }
    }

    private static Object parseByteArray(int length,
                                  ByteBuffer buf, ConstantPool constPool) {
        byte[] result = new byte[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'B') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = (byte) constPool.getIntAt(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseCharArray(int length,
                                  ByteBuffer buf, ConstantPool constPool) {
        char[] result = new char[length];
        boolean typeMismatch = false;
        byte tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'C') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = (char) constPool.getIntAt(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseDoubleArray(int length,
                                    ByteBuffer buf, ConstantPool constPool) {
        double[] result = new  double[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'D') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = constPool.getDoubleAt(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseFloatArray(int length,
                                   ByteBuffer buf, ConstantPool constPool) {
        float[] result = new float[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'F') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = constPool.getFloatAt(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseIntArray(int length,
                                 ByteBuffer buf, ConstantPool constPool) {
        int[] result = new  int[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'I') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = constPool.getIntAt(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseLongArray(int length,
                                  ByteBuffer buf, ConstantPool constPool) {
        long[] result = new long[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'J') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = constPool.getLongAt(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseShortArray(int length,
                                   ByteBuffer buf, ConstantPool constPool) {
        short[] result = new short[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'S') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = (short) constPool.getIntAt(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseBooleanArray(int length,
                                     ByteBuffer buf, ConstantPool constPool) {
        boolean[] result = new boolean[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 'Z') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = (constPool.getIntAt(index) != 0);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseStringArray(int length,
                                    ByteBuffer buf,  ConstantPool constPool) {
        String[] result = new String[length];
        boolean typeMismatch = false;
        int tag = 0;

        for (int i = 0; i < length; i++) {
            tag = buf.get();
            if (tag == 's') {
                int index = buf.getShort() & 0xFFFF;
                result[i] = constPool.getUTF8At(index);
            } else {
                skipMemberValue(tag, buf);
                typeMismatch = true;
            }
        }
        return typeMismatch ? exceptionProxy(tag) : result;
    }

    private static Object parseClassArray(int length,
                                          ByteBuffer buf,
                                          ConstantPool constPool,
                                          Class<?> container) {
        return parseArrayElements(new Class<?>[length],
                buf, 'c', () -> parseClassValue(buf, constPool, container));
    }

    private static Object parseEnumArray(int length, Class<? extends Enum<?>> enumType,
                                         ByteBuffer buf,
                                         ConstantPool constPool,
                                         Class<?> container) {
        return parseArrayElements((Object[]) Array.newInstance(enumType, length),
                buf, 'e', () -> parseEnumValue(enumType, buf, constPool, container));
    }

    private static Object parseAnnotationArray(int length,
                                               Class<? extends Annotation> annotationType,
                                               ByteBuffer buf,
                                               ConstantPool constPool,
                                               Class<?> container) {
        return parseArrayElements((Object[]) Array.newInstance(annotationType, length),
                buf, '@', () -> parseAnnotation(buf, constPool, container, true));
    }

    private static Object parseArrayElements(Object[] result,
                                             ByteBuffer buf,
                                             int expectedTag,
                                             Supplier<Object> parseElement) {
        Object exceptionProxy = null;
        for (int i = 0; i < result.length; i++) {
            int tag = buf.get();
            if (tag == expectedTag) {
                Object value = parseElement.get();
                if (value instanceof ExceptionProxy) {
                    if (exceptionProxy == null) exceptionProxy = (ExceptionProxy) value;
                } else {
                    result[i] = value;
                }
            } else {
                skipMemberValue(tag, buf);
                if (exceptionProxy == null) exceptionProxy = exceptionProxy(tag);
            }
        }
        return (exceptionProxy != null) ? exceptionProxy : result;
    }

    
Returns an appropriate exception proxy for a mismatching array
annotation where the erroneous array has the specified tag.
/**
     * Returns an appropriate exception proxy for a mismatching array
     * annotation where the erroneous array has the specified tag.
     */
    private static ExceptionProxy exceptionProxy(int tag) {
        return new AnnotationTypeMismatchExceptionProxy(
            "Array with component tag: " + tag);
    }

    
Skips the annotation at the current position in the specified
byte buffer.  The cursor of the byte buffer must point to
an "annotation structure" OR two bytes into an annotation
structure (i.e., after the type index).
@parameter
complete true if the byte buffer points to the beginning
    of an annotation structure (rather than two bytes in)./**
     * Skips the annotation at the current position in the specified
     * byte buffer.  The cursor of the byte buffer must point to
     * an "annotation structure" OR two bytes into an annotation
     * structure (i.e., after the type index).
     *
     * @parameter complete true if the byte buffer points to the beginning
     *     of an annotation structure (rather than two bytes in).
     */
    private static void skipAnnotation(ByteBuffer buf, boolean complete) {
        if (complete)
            buf.getShort();   // Skip type index
        int numMembers = buf.getShort() & 0xFFFF;
        for (int i = 0; i < numMembers; i++) {
            buf.getShort();   // Skip memberNameIndex
            skipMemberValue(buf);
        }
    }

    
Skips the annotation member value at the current position in the
specified byte buffer.  The cursor of the byte buffer must point to a
"member_value structure."
/**
     * Skips the annotation member value at the current position in the
     * specified byte buffer.  The cursor of the byte buffer must point to a
     * "member_value structure."
     */
    private static void skipMemberValue(ByteBuffer buf) {
        int tag = buf.get();
        skipMemberValue(tag, buf);
    }

    
Skips the annotation member value at the current position in the
specified byte buffer.  The cursor of the byte buffer must point
immediately after the tag in a "member_value structure."
/**
     * Skips the annotation member value at the current position in the
     * specified byte buffer.  The cursor of the byte buffer must point
     * immediately after the tag in a "member_value structure."
     */
    private static void skipMemberValue(int tag, ByteBuffer buf) {
        switch(tag) {
          case 'e': // Enum value
            buf.getInt();  // (Two shorts, actually.)
            break;
          case '@':
            skipAnnotation(buf, true);
            break;
          case '[':
            skipArray(buf);
            break;
          default:
            // Class, primitive, or String
            buf.getShort();
        }
    }

    
Skips the array value at the current position in the specified byte
buffer.  The cursor of the byte buffer must point to an array value
struct.
/**
     * Skips the array value at the current position in the specified byte
     * buffer.  The cursor of the byte buffer must point to an array value
     * struct.
     */
    private static void skipArray(ByteBuffer buf) {
        int length = buf.getShort() & 0xFFFF;
        for (int i = 0; i < length; i++)
            skipMemberValue(buf);
    }

    
Searches for given element in given array by identity. Returns true if found false if not. /**
     * Searches for given {@code element} in given {@code array} by identity.
     * Returns {@code true} if found {@code false} if not.
     */
    private static boolean contains(Object[] array, Object element) {
        for (Object e : array)
            if (e == element)
                return true;
        return false;
    }

    /*
     * This method converts the annotation map returned by the parseAnnotations()
     * method to an array.  It is called by Field.getDeclaredAnnotations(),
     * Method.getDeclaredAnnotations(), and Constructor.getDeclaredAnnotations().
     * This avoids the reflection classes to load the Annotation class until
     * it is needed.
     */
    private static final Annotation[] EMPTY_ANNOTATION_ARRAY = new Annotation[0];
    public static Annotation[] toArray(Map<Class<? extends Annotation>, Annotation> annotations) {
        return annotations.values().toArray(EMPTY_ANNOTATION_ARRAY);
    }

    static Annotation[] getEmptyAnnotationArray() { return EMPTY_ANNOTATION_ARRAY; }
}