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	/*
	* Copyright (c) 1996, 2021, 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 java.lang.reflect;

	import jdk.internal.access.SharedSecrets;
	import jdk.internal.reflect.CallerSensitive;
	import jdk.internal.reflect.ConstructorAccessor;
	import jdk.internal.reflect.Reflection;
	import jdk.internal.vm.annotation.ForceInline;
	import sun.reflect.annotation.TypeAnnotation;
	import sun.reflect.annotation.TypeAnnotationParser;
	import sun.reflect.generics.repository.ConstructorRepository;
	import sun.reflect.generics.factory.CoreReflectionFactory;
	import sun.reflect.generics.factory.GenericsFactory;
	import sun.reflect.generics.scope.ConstructorScope;
	import java.lang.annotation.Annotation;
	import java.lang.annotation.AnnotationFormatError;
	import java.util.StringJoiner;

	/**
	* {@code Constructor} provides information about, and access to, a single
	* constructor for a class.
	*
	* <p>{@code Constructor} permits widening conversions to occur when matching the
	* actual parameters to newInstance() with the underlying
	* constructor's formal parameters, but throws an
	* {@code IllegalArgumentException} if a narrowing conversion would occur.
	*
	* @param <T> the class in which the constructor is declared
	*
	* @see Member
	* @see java.lang.Class
	* @see java.lang.Class#getConstructors()
	* @see java.lang.Class#getConstructor(Class[])
	* @see java.lang.Class#getDeclaredConstructors()
	*
	* @author Kenneth Russell
	* @author Nakul Saraiya
	* @since 1.1
	*/
	public final class Constructor<T> extends Executable {
	private Class<T> clazz;
	private int slot;
	private Class<?>[] parameterTypes;
	private Class<?>[] exceptionTypes;
	private int modifiers;
	// Generics and annotations support
	private transient String signature;
	// generic info repository; lazily initialized
	private transient ConstructorRepository genericInfo;
	private byte[] annotations;
	private byte[] parameterAnnotations;

	// Generics infrastructure
	// Accessor for factory
	private GenericsFactory getFactory() {
	// create scope and factory
	return CoreReflectionFactory.make(this, ConstructorScope.make(this));
	}

	// Accessor for generic info repository
	@Override
	ConstructorRepository getGenericInfo() {
	// lazily initialize repository if necessary
	if (genericInfo == null) {
	// create and cache generic info repository
	genericInfo =
	ConstructorRepository.make(getSignature(),
	getFactory());
	}
	return genericInfo; //return cached repository
	}

	private volatile ConstructorAccessor constructorAccessor;
	// For sharing of ConstructorAccessors. This branching structure
	// is currently only two levels deep (i.e., one root Constructor
	// and potentially many Constructor objects pointing to it.)
	//
	// If this branching structure would ever contain cycles, deadlocks can
	// occur in annotation code.
	private Constructor<T> root;

	@Override
	Constructor<T> getRoot() {
	return root;
	}

	/**
	* Package-private constructor used by ReflectAccess to enable
	* instantiation of these objects in Java code from the java.lang
	* package via jdk.internal.access.JavaLangReflectAccess.
	*/
	Constructor(Class<T> declaringClass,
	Class<?>[] parameterTypes,
	Class<?>[] checkedExceptions,
	int modifiers,
	int slot,
	String signature,
	byte[] annotations,
	byte[] parameterAnnotations) {
	this.clazz = declaringClass;
	this.parameterTypes = parameterTypes;
	this.exceptionTypes = checkedExceptions;
	this.modifiers = modifiers;
	this.slot = slot;
	this.signature = signature;
	this.annotations = annotations;
	this.parameterAnnotations = parameterAnnotations;
	}

	/**
	* Package-private routine (exposed to java.lang.Class via
	* ReflectAccess) which returns a copy of this Constructor. The copy's
	* "root" field points to this Constructor.
	*/
	Constructor<T> copy() {
	// This routine enables sharing of ConstructorAccessor objects
	// among Constructor objects which refer to the same underlying
	// method in the VM. (All of this contortion is only necessary
	// because of the "accessibility" bit in AccessibleObject,
	// which implicitly requires that new java.lang.reflect
	// objects be fabricated for each reflective call on Class
	// objects.)
	if (this.root != null)
	throw new IllegalArgumentException("Can not copy a non-root Constructor");

	Constructor<T> res = new Constructor<>(clazz,
	parameterTypes,
	exceptionTypes, modifiers, slot,
	signature,
	annotations,
	parameterAnnotations);
	res.root = this;
	// Might as well eagerly propagate this if already present
	res.constructorAccessor = constructorAccessor;
	return res;
	}

	/**
	* {@inheritDoc}
	*
	* <p> A {@code SecurityException} is also thrown if this object is a
	* {@code Constructor} object for the class {@code Class} and {@code flag}
	* is true. </p>
	*
	* @param flag {@inheritDoc}
	*
	* @throws InaccessibleObjectException {@inheritDoc}
	* @throws SecurityException if the request is denied by the security manager
	* or this is a constructor for {@code java.lang.Class}
	*
	*/
	@Override
	@CallerSensitive
	public void setAccessible(boolean flag) {
	AccessibleObject.checkPermission();
	if (flag) {
	checkCanSetAccessible(Reflection.getCallerClass());
	}
	setAccessible0(flag);
	}

	@Override
	void checkCanSetAccessible(Class<?> caller) {
	checkCanSetAccessible(caller, clazz);
	if (clazz == Class.class) {
	// can we change this to InaccessibleObjectException?
	throw new SecurityException("Cannot make a java.lang.Class"
	+ " constructor accessible");
	}
	}

	@Override
	boolean hasGenericInformation() {
	return (getSignature() != null);
	}

	@Override
	byte[] getAnnotationBytes() {
	return annotations;
	}

	/**
	* Returns the {@code Class} object representing the class that
	* declares the constructor represented by this object.
	*/
	@Override
	public Class<T> getDeclaringClass() {
	return clazz;
	}

	/**
	* Returns the name of this constructor, as a string. This is
	* the binary name of the constructor's declaring class.
	*/
	@Override
	public String getName() {
	return getDeclaringClass().getName();
	}

	/**
	* {@inheritDoc}
	* @jls 8.8.3 Constructor Modifiers
	*/
	@Override
	public int getModifiers() {
	return modifiers;
	}

	/**
	* {@inheritDoc}
	* @throws GenericSignatureFormatError {@inheritDoc}
	* @since 1.5
	*/
	@Override
	@SuppressWarnings({"rawtypes", "unchecked"})
	public TypeVariable<Constructor<T>>[] getTypeParameters() {
	if (getSignature() != null) {
	return (TypeVariable<Constructor<T>>[])getGenericInfo().getTypeParameters();
	} else
	return (TypeVariable<Constructor<T>>[])new TypeVariable[0];
	}


	@Override
	Class<?>[] getSharedParameterTypes() {
	return parameterTypes;
	}

	@Override
	Class<?>[] getSharedExceptionTypes() {
	return exceptionTypes;
	}

	/**
	* {@inheritDoc}
	*/
	@Override
	public Class<?>[] getParameterTypes() {
	return parameterTypes.clone();
	}

	/**
	* {@inheritDoc}
	* @since 1.8
	*/
	public int getParameterCount() { return parameterTypes.length; }

	/**
	* {@inheritDoc}
	* @throws GenericSignatureFormatError {@inheritDoc}
	* @throws TypeNotPresentException {@inheritDoc}
	* @throws MalformedParameterizedTypeException {@inheritDoc}
	* @since 1.5
	*/
	@Override
	public Type[] getGenericParameterTypes() {
	return super.getGenericParameterTypes();
	}

	/**
	* {@inheritDoc}
	*/
	@Override
	public Class<?>[] getExceptionTypes() {
	return exceptionTypes.clone();
	}


	/**
	* {@inheritDoc}
	* @throws GenericSignatureFormatError {@inheritDoc}
	* @throws TypeNotPresentException {@inheritDoc}
	* @throws MalformedParameterizedTypeException {@inheritDoc}
	* @since 1.5
	*/
	@Override
	public Type[] getGenericExceptionTypes() {
	return super.getGenericExceptionTypes();
	}

	/**
	* Compares this {@code Constructor} against the specified object.
	* Returns true if the objects are the same. Two {@code Constructor} objects are
	* the same if they were declared by the same class and have the
	* same formal parameter types.
	*/
	public boolean equals(Object obj) {
	if (obj instanceof Constructor<?> other) {
	if (getDeclaringClass() == other.getDeclaringClass()) {
	return equalParamTypes(parameterTypes, other.parameterTypes);
	}
	}
	return false;
	}

	/**
	* Returns a hashcode for this {@code Constructor}. The hashcode is
	* the same as the hashcode for the underlying constructor's
	* declaring class name.
	*/
	public int hashCode() {
	return getDeclaringClass().getName().hashCode();
	}

	/**
	* Returns a string describing this {@code Constructor}. The string is
	* formatted as the constructor access modifiers, if any,
	* followed by the fully-qualified name of the declaring class,
	* followed by a parenthesized, comma-separated list of the
	* constructor's formal parameter types. For example:
	* <pre>{@code
	* public java.util.HashMap(int,float)
	* }</pre>
	*
	* <p>If the constructor is declared to throw exceptions, the
	* parameter list is followed by a space, followed by the word
	* "{@code throws}" followed by a comma-separated list of the
	* thrown exception types.
	*
	* <p>The only possible modifiers for constructors are the access
	* modifiers {@code public}, {@code protected} or
	* {@code private}. Only one of these may appear, or none if the
	* constructor has default (package) access.
	*
	* @return a string describing this {@code Constructor}
	* @jls 8.8.3 Constructor Modifiers
	* @jls 8.9.2 Enum Body Declarations
	*/
	public String toString() {
	return sharedToString(Modifier.constructorModifiers(),
	false,
	parameterTypes,
	exceptionTypes);
	}

	@Override
	void specificToStringHeader(StringBuilder sb) {
	sb.append(getDeclaringClass().getTypeName());
	}

	@Override
	String toShortString() {
	StringBuilder sb = new StringBuilder("constructor ");
	sb.append(getDeclaringClass().getTypeName());
	sb.append('(');
	StringJoiner sj = new StringJoiner(",");
	for (Class<?> parameterType : getParameterTypes()) {
	sj.add(parameterType.getTypeName());
	}
	sb.append(sj);
	sb.append(')');
	return sb.toString();
	}

	/**
	* Returns a string describing this {@code Constructor},
	* including type parameters. The string is formatted as the
	* constructor access modifiers, if any, followed by an
	* angle-bracketed comma separated list of the constructor's type
	* parameters, if any, including informative bounds of the
	* type parameters, if any, followed by the fully-qualified name of the
	* declaring class, followed by a parenthesized, comma-separated
	* list of the constructor's generic formal parameter types.
	*
	* If this constructor was declared to take a variable number of
	* arguments, instead of denoting the last parameter as
	* "<code><i>Type</i>[]</code>", it is denoted as
	* "<code><i>Type</i>...</code>".
	*
	* A space is used to separate access modifiers from one another
	* and from the type parameters or class name. If there are no
	* type parameters, the type parameter list is elided; if the type
	* parameter list is present, a space separates the list from the
	* class name. If the constructor is declared to throw
	* exceptions, the parameter list is followed by a space, followed
	* by the word "{@code throws}" followed by a
	* comma-separated list of the generic thrown exception types.
	*
	* <p>The only possible modifiers for constructors are the access
	* modifiers {@code public}, {@code protected} or
	* {@code private}. Only one of these may appear, or none if the
	* constructor has default (package) access.
	*
	* @return a string describing this {@code Constructor},
	* include type parameters
	*
	* @since 1.5
	* @jls 8.8.3 Constructor Modifiers
	* @jls 8.9.2 Enum Body Declarations
	*/
	@Override
	public String toGenericString() {
	return sharedToGenericString(Modifier.constructorModifiers(), false);
	}

	@Override
	void specificToGenericStringHeader(StringBuilder sb) {
	specificToStringHeader(sb);
	}

	/**
	* Uses the constructor represented by this {@code Constructor} object to
	* create and initialize a new instance of the constructor's
	* declaring class, with the specified initialization parameters.
	* Individual parameters are automatically unwrapped to match
	* primitive formal parameters, and both primitive and reference
	* parameters are subject to method invocation conversions as necessary.
	*
	* <p>If the number of formal parameters required by the underlying constructor
	* is 0, the supplied {@code initargs} array may be of length 0 or null.
	*
	* <p>If the constructor's declaring class is an inner class in a
	* non-static context, the first argument to the constructor needs
	* to be the enclosing instance; see section {@jls 15.9.3} of
	* <cite>The Java Language Specification</cite>.
	*
	* <p>If the required access and argument checks succeed and the
	* instantiation will proceed, the constructor's declaring class
	* is initialized if it has not already been initialized.
	*
	* <p>If the constructor completes normally, returns the newly
	* created and initialized instance.
	*
	* @param initargs array of objects to be passed as arguments to
	* the constructor call; values of primitive types are wrapped in
	* a wrapper object of the appropriate type (e.g. a {@code float}
	* in a {@link java.lang.Float Float})
	*
	* @return a new object created by calling the constructor
	* this object represents
	*
	* @throws IllegalAccessException if this {@code Constructor} object
	* is enforcing Java language access control and the underlying
	* constructor is inaccessible.
	* @throws IllegalArgumentException if the number of actual
	* and formal parameters differ; if an unwrapping
	* conversion for primitive arguments fails; or if,
	* after possible unwrapping, a parameter value
	* cannot be converted to the corresponding formal
	* parameter type by a method invocation conversion; if
	* this constructor pertains to an enum class.
	* @throws InstantiationException if the class that declares the
	* underlying constructor represents an abstract class.
	* @throws InvocationTargetException if the underlying constructor
	* throws an exception.
	* @throws ExceptionInInitializerError if the initialization provoked
	* by this method fails.
	*/
	@CallerSensitive
	@ForceInline // to ensure Reflection.getCallerClass optimization
	public T newInstance(Object ... initargs)
	throws InstantiationException, IllegalAccessException,
	IllegalArgumentException, InvocationTargetException
	{
	Class<?> caller = override ? null : Reflection.getCallerClass();
	return newInstanceWithCaller(initargs, !override, caller);
	}

	/* package-private */
	T newInstanceWithCaller(Object[] args, boolean checkAccess, Class<?> caller)
	throws InstantiationException, IllegalAccessException,
	InvocationTargetException
	{
	if (checkAccess)
	checkAccess(caller, clazz, clazz, modifiers);

	if ((clazz.getModifiers() & Modifier.ENUM) != 0)
	throw new IllegalArgumentException("Cannot reflectively create enum objects");

	ConstructorAccessor ca = constructorAccessor; // read volatile
	if (ca == null) {
	ca = acquireConstructorAccessor();
	}
	@SuppressWarnings("unchecked")
	T inst = (T) ca.newInstance(args);
	return inst;
	}

	/**
	* {@inheritDoc}
	* @since 1.5
	* @jls 8.4.1 Formal Parameters
	*/
	@Override
	public boolean isVarArgs() {
	return super.isVarArgs();
	}

	/**
	* {@inheritDoc}
	* @jls 13.1 The Form of a Binary
	* @jvms 4.6 Methods
	* @since 1.5
	* @see <a
	* href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
	* programming language and JVM modeling in core reflection</a>
	*/
	@Override
	public boolean isSynthetic() {
	return super.isSynthetic();
	}

	// NOTE that there is no synchronization used here. It is correct
	// (though not efficient) to generate more than one
	// ConstructorAccessor for a given Constructor. However, avoiding
	// synchronization will probably make the implementation more
	// scalable.
	private ConstructorAccessor acquireConstructorAccessor() {
	// First check to see if one has been created yet, and take it
	// if so.
	ConstructorAccessor tmp = null;
	if (root != null) tmp = root.getConstructorAccessor();
	if (tmp != null) {
	constructorAccessor = tmp;
	} else {
	// Otherwise fabricate one and propagate it up to the root
	tmp = reflectionFactory.newConstructorAccessor(this);
	setConstructorAccessor(tmp);
	}

	return tmp;
	}

	// Returns ConstructorAccessor for this Constructor object, not
	// looking up the chain to the root
	ConstructorAccessor getConstructorAccessor() {
	return constructorAccessor;
	}

	// Sets the ConstructorAccessor for this Constructor object and
	// (recursively) its root
	void setConstructorAccessor(ConstructorAccessor accessor) {
	constructorAccessor = accessor;
	// Propagate up
	if (root != null) {
	root.setConstructorAccessor(accessor);
	}
	}

	int getSlot() {
	return slot;
	}

	String getSignature() {
	return signature;
	}

	byte[] getRawAnnotations() {
	return annotations;
	}

	byte[] getRawParameterAnnotations() {
	return parameterAnnotations;
	}


	/**
	* {@inheritDoc}
	*
	* @throws NullPointerException {@inheritDoc}
	* @since 1.5
	*/
	@Override
	public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
	return super.getAnnotation(annotationClass);
	}

	/**
	* {@inheritDoc}
	* @since 1.5
	*/
	@Override
	public Annotation[] getDeclaredAnnotations() {
	return super.getDeclaredAnnotations();
	}

	/**
	* {@inheritDoc}
	* @since 1.5
	*/
	@Override
	public Annotation[][] getParameterAnnotations() {
	return sharedGetParameterAnnotations(parameterTypes, parameterAnnotations);
	}

	@Override
	boolean handleParameterNumberMismatch(int resultLength, Class<?>[] parameterTypes) {
	int numParameters = parameterTypes.length;
	Class<?> declaringClass = getDeclaringClass();
	if (declaringClass.isEnum()) {
	return resultLength + 2 == numParameters &&
	parameterTypes[0] == String.class &&
	parameterTypes[1] == int.class;
	} else if (
	declaringClass.isAnonymousClass() \|\|
	declaringClass.isLocalClass() )
	return false; // Can't do reliable parameter counting
	else {
	if (declaringClass.isMemberClass() &&
	((declaringClass.getModifiers() & Modifier.STATIC) == 0) &&
	resultLength + 1 == numParameters) {
	return true;
	} else {
	throw new AnnotationFormatError(
	"Parameter annotations don't match number of parameters");
	}
	}
	}

	/**
	* {@inheritDoc}
	* @since 1.8
	*/
	@Override
	public AnnotatedType getAnnotatedReturnType() {
	return getAnnotatedReturnType0(getDeclaringClass());
	}

	/**
	* {@inheritDoc}
	* @since 1.8
	*/
	@Override
	public AnnotatedType getAnnotatedReceiverType() {
	Class<?> thisDeclClass = getDeclaringClass();
	Class<?> enclosingClass = thisDeclClass.getEnclosingClass();

	if (enclosingClass == null) {
	// A Constructor for a top-level class
	return null;
	}

	Class<?> outerDeclaringClass = thisDeclClass.getDeclaringClass();
	if (outerDeclaringClass == null) {
	// A constructor for a local or anonymous class
	return null;
	}

	// Either static nested or inner class
	if (Modifier.isStatic(thisDeclClass.getModifiers())) {
	// static nested
	return null;
	}

	// A Constructor for an inner class
	return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes0(),
	SharedSecrets.getJavaLangAccess().
	getConstantPool(thisDeclClass),
	this,
	thisDeclClass,
	parameterize(enclosingClass),
	TypeAnnotation.TypeAnnotationTarget.METHOD_RECEIVER);
	}
	}

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