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	/*
	* 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.
	*/

	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* ASM: a very small and fast Java bytecode manipulation framework
	* Copyright (c) 2000-2011 INRIA, France Telecom
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/
	package jdk.internal.org.objectweb.asm;

	/**
	* A reference to a type appearing in a class, field or method declaration, or on an instruction.
	* Such a reference designates the part of the class where the referenced type is appearing (e.g. an
	* 'extends', 'implements' or 'throws' clause, a 'new' instruction, a 'catch' clause, a type cast, a
	* local variable declaration, etc).
	*
	* @author Eric Bruneton
	*/
	public class TypeReference {

	/**
	* The sort of type references that target a type parameter of a generic class. See {@link
	* #getSort}.
	*/
	public static final int CLASS_TYPE_PARAMETER = 0x00;

	/**
	* The sort of type references that target a type parameter of a generic method. See {@link
	* #getSort}.
	*/
	public static final int METHOD_TYPE_PARAMETER = 0x01;

	/**
	* The sort of type references that target the super class of a class or one of the interfaces it
	* implements. See {@link #getSort}.
	*/
	public static final int CLASS_EXTENDS = 0x10;

	/**
	* The sort of type references that target a bound of a type parameter of a generic class. See
	* {@link #getSort}.
	*/
	public static final int CLASS_TYPE_PARAMETER_BOUND = 0x11;

	/**
	* The sort of type references that target a bound of a type parameter of a generic method. See
	* {@link #getSort}.
	*/
	public static final int METHOD_TYPE_PARAMETER_BOUND = 0x12;

	/** The sort of type references that target the type of a field. See {@link #getSort}. */
	public static final int FIELD = 0x13;

	/** The sort of type references that target the return type of a method. See {@link #getSort}. */
	public static final int METHOD_RETURN = 0x14;

	/**
	* The sort of type references that target the receiver type of a method. See {@link #getSort}.
	*/
	public static final int METHOD_RECEIVER = 0x15;

	/**
	* The sort of type references that target the type of a formal parameter of a method. See {@link
	* #getSort}.
	*/
	public static final int METHOD_FORMAL_PARAMETER = 0x16;

	/**
	* The sort of type references that target the type of an exception declared in the throws clause
	* of a method. See {@link #getSort}.
	*/
	public static final int THROWS = 0x17;

	/**
	* The sort of type references that target the type of a local variable in a method. See {@link
	* #getSort}.
	*/
	public static final int LOCAL_VARIABLE = 0x40;

	/**
	* The sort of type references that target the type of a resource variable in a method. See {@link
	* #getSort}.
	*/
	public static final int RESOURCE_VARIABLE = 0x41;

	/**
	* The sort of type references that target the type of the exception of a 'catch' clause in a
	* method. See {@link #getSort}.
	*/
	public static final int EXCEPTION_PARAMETER = 0x42;

	/**
	* The sort of type references that target the type declared in an 'instanceof' instruction. See
	* {@link #getSort}.
	*/
	public static final int INSTANCEOF = 0x43;

	/**
	* The sort of type references that target the type of the object created by a 'new' instruction.
	* See {@link #getSort}.
	*/
	public static final int NEW = 0x44;

	/**
	* The sort of type references that target the receiver type of a constructor reference. See
	* {@link #getSort}.
	*/
	public static final int CONSTRUCTOR_REFERENCE = 0x45;

	/**
	* The sort of type references that target the receiver type of a method reference. See {@link
	* #getSort}.
	*/
	public static final int METHOD_REFERENCE = 0x46;

	/**
	* The sort of type references that target the type declared in an explicit or implicit cast
	* instruction. See {@link #getSort}.
	*/
	public static final int CAST = 0x47;

	/**
	* The sort of type references that target a type parameter of a generic constructor in a
	* constructor call. See {@link #getSort}.
	*/
	public static final int CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT = 0x48;

	/**
	* The sort of type references that target a type parameter of a generic method in a method call.
	* See {@link #getSort}.
	*/
	public static final int METHOD_INVOCATION_TYPE_ARGUMENT = 0x49;

	/**
	* The sort of type references that target a type parameter of a generic constructor in a
	* constructor reference. See {@link #getSort}.
	*/
	public static final int CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT = 0x4A;

	/**
	* The sort of type references that target a type parameter of a generic method in a method
	* reference. See {@link #getSort}.
	*/
	public static final int METHOD_REFERENCE_TYPE_ARGUMENT = 0x4B;

	/**
	* The target_type and target_info structures - as defined in the Java Virtual Machine
	* Specification (JVMS) - corresponding to this type reference. target_type uses one byte, and all
	* the target_info union fields use up to 3 bytes (except localvar_target, handled with the
	* specific method {@link MethodVisitor#visitLocalVariableAnnotation}). Thus, both structures can
	* be stored in an int.
	*
	* <p>This int field stores target_type (called the TypeReference 'sort' in the public API of this
	* class) in its most significant byte, followed by the target_info fields. Depending on
	* target_type, 1, 2 or even 3 least significant bytes of this field are unused. target_info
	* fields which reference bytecode offsets are set to 0 (these offsets are ignored in ClassReader,
	* and recomputed in MethodWriter).
	*
	* @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.20">JVMS
	* 4.7.20</a>
	* @see <a
	* href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.20.1">JVMS
	* 4.7.20.1</a>
	*/
	private final int targetTypeAndInfo;

	/**
	* Constructs a new TypeReference.
	*
	* @param typeRef the int encoded value of the type reference, as received in a visit method
	* related to type annotations, such as {@link ClassVisitor#visitTypeAnnotation}.
	*/
	public TypeReference(final int typeRef) {
	this.targetTypeAndInfo = typeRef;
	}

	/**
	* Returns a type reference of the given sort.
	*
	* @param sort one of {@link #FIELD}, {@link #METHOD_RETURN}, {@link #METHOD_RECEIVER}, {@link
	* #LOCAL_VARIABLE}, {@link #RESOURCE_VARIABLE}, {@link #INSTANCEOF}, {@link #NEW}, {@link
	* #CONSTRUCTOR_REFERENCE}, or {@link #METHOD_REFERENCE}.
	* @return a type reference of the given sort.
	*/
	public static TypeReference newTypeReference(final int sort) {
	return new TypeReference(sort << 24);
	}

	/**
	* Returns a reference to a type parameter of a generic class or method.
	*
	* @param sort one of {@link #CLASS_TYPE_PARAMETER} or {@link #METHOD_TYPE_PARAMETER}.
	* @param paramIndex the type parameter index.
	* @return a reference to the given generic class or method type parameter.
	*/
	public static TypeReference newTypeParameterReference(final int sort, final int paramIndex) {
	return new TypeReference((sort << 24) \| (paramIndex << 16));
	}

	/**
	* Returns a reference to a type parameter bound of a generic class or method.
	*
	* @param sort one of {@link #CLASS_TYPE_PARAMETER} or {@link #METHOD_TYPE_PARAMETER}.
	* @param paramIndex the type parameter index.
	* @param boundIndex the type bound index within the above type parameters.
	* @return a reference to the given generic class or method type parameter bound.
	*/
	public static TypeReference newTypeParameterBoundReference(
	final int sort, final int paramIndex, final int boundIndex) {
	return new TypeReference((sort << 24) \| (paramIndex << 16) \| (boundIndex << 8));
	}

	/**
	* Returns a reference to the super class or to an interface of the 'implements' clause of a
	* class.
	*
	* @param itfIndex the index of an interface in the 'implements' clause of a class, or -1 to
	* reference the super class of the class.
	* @return a reference to the given super type of a class.
	*/
	public static TypeReference newSuperTypeReference(final int itfIndex) {
	return new TypeReference((CLASS_EXTENDS << 24) \| ((itfIndex & 0xFFFF) << 8));
	}

	/**
	* Returns a reference to the type of a formal parameter of a method.
	*
	* @param paramIndex the formal parameter index.
	* @return a reference to the type of the given method formal parameter.
	*/
	public static TypeReference newFormalParameterReference(final int paramIndex) {
	return new TypeReference((METHOD_FORMAL_PARAMETER << 24) \| (paramIndex << 16));
	}

	/**
	* Returns a reference to the type of an exception, in a 'throws' clause of a method.
	*
	* @param exceptionIndex the index of an exception in a 'throws' clause of a method.
	* @return a reference to the type of the given exception.
	*/
	public static TypeReference newExceptionReference(final int exceptionIndex) {
	return new TypeReference((THROWS << 24) \| (exceptionIndex << 8));
	}

	/**
	* Returns a reference to the type of the exception declared in a 'catch' clause of a method.
	*
	* @param tryCatchBlockIndex the index of a try catch block (using the order in which they are
	* visited with visitTryCatchBlock).
	* @return a reference to the type of the given exception.
	*/
	public static TypeReference newTryCatchReference(final int tryCatchBlockIndex) {
	return new TypeReference((EXCEPTION_PARAMETER << 24) \| (tryCatchBlockIndex << 8));
	}

	/**
	* Returns a reference to the type of a type argument in a constructor or method call or
	* reference.
	*
	* @param sort one of {@link #CAST}, {@link #CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT}, {@link
	* #METHOD_INVOCATION_TYPE_ARGUMENT}, {@link #CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT}, or {@link
	* #METHOD_REFERENCE_TYPE_ARGUMENT}.
	* @param argIndex the type argument index.
	* @return a reference to the type of the given type argument.
	*/
	public static TypeReference newTypeArgumentReference(final int sort, final int argIndex) {
	return new TypeReference((sort << 24) \| argIndex);
	}

	/**
	* Returns the sort of this type reference.
	*
	* @return one of {@link #CLASS_TYPE_PARAMETER}, {@link #METHOD_TYPE_PARAMETER}, {@link
	* #CLASS_EXTENDS}, {@link #CLASS_TYPE_PARAMETER_BOUND}, {@link #METHOD_TYPE_PARAMETER_BOUND},
	* {@link #FIELD}, {@link #METHOD_RETURN}, {@link #METHOD_RECEIVER}, {@link
	* #METHOD_FORMAL_PARAMETER}, {@link #THROWS}, {@link #LOCAL_VARIABLE}, {@link
	* #RESOURCE_VARIABLE}, {@link #EXCEPTION_PARAMETER}, {@link #INSTANCEOF}, {@link #NEW},
	* {@link #CONSTRUCTOR_REFERENCE}, {@link #METHOD_REFERENCE}, {@link #CAST}, {@link
	* #CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT}, {@link #METHOD_INVOCATION_TYPE_ARGUMENT}, {@link
	* #CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT}, or {@link #METHOD_REFERENCE_TYPE_ARGUMENT}.
	*/
	public int getSort() {
	return targetTypeAndInfo >>> 24;
	}

	/**
	* Returns the index of the type parameter referenced by this type reference. This method must
	* only be used for type references whose sort is {@link #CLASS_TYPE_PARAMETER}, {@link
	* #METHOD_TYPE_PARAMETER}, {@link #CLASS_TYPE_PARAMETER_BOUND} or {@link
	* #METHOD_TYPE_PARAMETER_BOUND}.
	*
	* @return a type parameter index.
	*/
	public int getTypeParameterIndex() {
	return (targetTypeAndInfo & 0x00FF0000) >> 16;
	}

	/**
	* Returns the index of the type parameter bound, within the type parameter {@link
	* #getTypeParameterIndex}, referenced by this type reference. This method must only be used for
	* type references whose sort is {@link #CLASS_TYPE_PARAMETER_BOUND} or {@link
	* #METHOD_TYPE_PARAMETER_BOUND}.
	*
	* @return a type parameter bound index.
	*/
	public int getTypeParameterBoundIndex() {
	return (targetTypeAndInfo & 0x0000FF00) >> 8;
	}

	/**
	* Returns the index of the "super type" of a class that is referenced by this type reference.
	* This method must only be used for type references whose sort is {@link #CLASS_EXTENDS}.
	*
	* @return the index of an interface in the 'implements' clause of a class, or -1 if this type
	* reference references the type of the super class.
	*/
	public int getSuperTypeIndex() {
	return (short) ((targetTypeAndInfo & 0x00FFFF00) >> 8);
	}

	/**
	* Returns the index of the formal parameter whose type is referenced by this type reference. This
	* method must only be used for type references whose sort is {@link #METHOD_FORMAL_PARAMETER}.
	*
	* @return a formal parameter index.
	*/
	public int getFormalParameterIndex() {
	return (targetTypeAndInfo & 0x00FF0000) >> 16;
	}

	/**
	* Returns the index of the exception, in a 'throws' clause of a method, whose type is referenced
	* by this type reference. This method must only be used for type references whose sort is {@link
	* #THROWS}.
	*
	* @return the index of an exception in the 'throws' clause of a method.
	*/
	public int getExceptionIndex() {
	return (targetTypeAndInfo & 0x00FFFF00) >> 8;
	}

	/**
	* Returns the index of the try catch block (using the order in which they are visited with
	* visitTryCatchBlock), whose 'catch' type is referenced by this type reference. This method must
	* only be used for type references whose sort is {@link #EXCEPTION_PARAMETER} .
	*
	* @return the index of an exception in the 'throws' clause of a method.
	*/
	public int getTryCatchBlockIndex() {
	return (targetTypeAndInfo & 0x00FFFF00) >> 8;
	}

	/**
	* Returns the index of the type argument referenced by this type reference. This method must only
	* be used for type references whose sort is {@link #CAST}, {@link
	* #CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT}, {@link #METHOD_INVOCATION_TYPE_ARGUMENT}, {@link
	* #CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT}, or {@link #METHOD_REFERENCE_TYPE_ARGUMENT}.
	*
	* @return a type parameter index.
	*/
	public int getTypeArgumentIndex() {
	return targetTypeAndInfo & 0xFF;
	}

	/**
	* Returns the int encoded value of this type reference, suitable for use in visit methods related
	* to type annotations, like visitTypeAnnotation.
	*
	* @return the int encoded value of this type reference.
	*/
	public int getValue() {
	return targetTypeAndInfo;
	}

	/**
	* Puts the given target_type and target_info JVMS structures into the given ByteVector.
	*
	* @param targetTypeAndInfo a target_type and a target_info structures encoded as in {@link
	* #targetTypeAndInfo}. LOCAL_VARIABLE and RESOURCE_VARIABLE target types are not supported.
	* @param output where the type reference must be put.
	*/
	static void putTarget(final int targetTypeAndInfo, final ByteVector output) {
	switch (targetTypeAndInfo >>> 24) {
	case CLASS_TYPE_PARAMETER:
	case METHOD_TYPE_PARAMETER:
	case METHOD_FORMAL_PARAMETER:
	output.putShort(targetTypeAndInfo >>> 16);
	break;
	case FIELD:
	case METHOD_RETURN:
	case METHOD_RECEIVER:
	output.putByte(targetTypeAndInfo >>> 24);
	break;
	case CAST:
	case CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT:
	case METHOD_INVOCATION_TYPE_ARGUMENT:
	case CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT:
	case METHOD_REFERENCE_TYPE_ARGUMENT:
	output.putInt(targetTypeAndInfo);
	break;
	case CLASS_EXTENDS:
	case CLASS_TYPE_PARAMETER_BOUND:
	case METHOD_TYPE_PARAMETER_BOUND:
	case THROWS:
	case EXCEPTION_PARAMETER:
	case INSTANCEOF:
	case NEW:
	case CONSTRUCTOR_REFERENCE:
	case METHOD_REFERENCE:
	output.put12(targetTypeAndInfo >>> 24, (targetTypeAndInfo & 0xFFFF00) >> 8);
	break;
	default:
	throw new IllegalArgumentException();
	}
	}
	}

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