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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 non standard class, field, method or code attribute.
	*
	* @author Eric Bruneton
	* @author Eugene Kuleshov
	*/
	public class Attribute {

	/**
	* The type of this attribute.
	*/
	public final String type;

	/**
	* The raw value of this attribute, used only for unknown attributes.
	*/
	byte[] value;

	/**
	* The next attribute in this attribute list. May be <tt>null</tt>.
	*/
	Attribute next;

	/**
	* Constructs a new empty attribute.
	*
	* @param type
	* the type of the attribute.
	*/
	protected Attribute(final String type) {
	this.type = type;
	}

	/**
	* Returns <tt>true</tt> if this type of attribute is unknown. The default
	* implementation of this method always returns <tt>true</tt>.
	*
	* @return <tt>true</tt> if this type of attribute is unknown.
	*/
	public boolean isUnknown() {
	return true;
	}

	/**
	* Returns <tt>true</tt> if this type of attribute is a code attribute.
	*
	* @return <tt>true</tt> if this type of attribute is a code attribute.
	*/
	public boolean isCodeAttribute() {
	return false;
	}

	/**
	* Returns the labels corresponding to this attribute.
	*
	* @return the labels corresponding to this attribute, or <tt>null</tt> if
	* this attribute is not a code attribute that contains labels.
	*/
	protected Label[] getLabels() {
	return null;
	}

	/**
	* Reads a {@link #type type} attribute. This method must return a
	* <i>new</i> {@link Attribute} object, of type {@link #type type},
	* corresponding to the <tt>len</tt> bytes starting at the given offset, in
	* the given class reader.
	*
	* @param cr
	* the class that contains the attribute to be read.
	* @param off
	* index of the first byte of the attribute's content in
	* {@link ClassReader#b cr.b}. The 6 attribute header bytes,
	* containing the type and the length of the attribute, are not
	* taken into account here.
	* @param len
	* the length of the attribute's content.
	* @param buf
	* buffer to be used to call {@link ClassReader#readUTF8
	* readUTF8}, {@link ClassReader#readClass(int,char[]) readClass}
	* or {@link ClassReader#readConst readConst}.
	* @param codeOff
	* index of the first byte of code's attribute content in
	* {@link ClassReader#b cr.b}, or -1 if the attribute to be read
	* is not a code attribute. The 6 attribute header bytes,
	* containing the type and the length of the attribute, are not
	* taken into account here.
	* @param labels
	* the labels of the method's code, or <tt>null</tt> if the
	* attribute to be read is not a code attribute.
	* @return a <i>new</i> {@link Attribute} object corresponding to the given
	* bytes.
	*/
	protected Attribute read(final ClassReader cr, final int off,
	final int len, final char[] buf, final int codeOff,
	final Label[] labels) {
	Attribute attr = new Attribute(type);
	attr.value = new byte[len];
	System.arraycopy(cr.b, off, attr.value, 0, len);
	return attr;
	}

	/**
	* Returns the byte array form of this attribute.
	*
	* @param cw
	* the class to which this attribute must be added. This
	* parameter can be used to add to the constant pool of this
	* class the items that corresponds to this attribute.
	* @param code
	* the bytecode of the method corresponding to this code
	* attribute, or <tt>null</tt> if this attribute is not a code
	* attributes.
	* @param len
	* the length of the bytecode of the method corresponding to this
	* code attribute, or <tt>null</tt> if this attribute is not a
	* code attribute.
	* @param maxStack
	* the maximum stack size of the method corresponding to this
	* code attribute, or -1 if this attribute is not a code
	* attribute.
	* @param maxLocals
	* the maximum number of local variables of the method
	* corresponding to this code attribute, or -1 if this attribute
	* is not a code attribute.
	* @return the byte array form of this attribute.
	*/
	protected ByteVector write(final ClassWriter cw, final byte[] code,
	final int len, final int maxStack, final int maxLocals) {
	ByteVector v = new ByteVector();
	v.data = value;
	v.length = value.length;
	return v;
	}

	/**
	* Returns the length of the attribute list that begins with this attribute.
	*
	* @return the length of the attribute list that begins with this attribute.
	*/
	final int getCount() {
	int count = 0;
	Attribute attr = this;
	while (attr != null) {
	count += 1;
	attr = attr.next;
	}
	return count;
	}

	/**
	* Returns the size of all the attributes in this attribute list.
	*
	* @param cw
	* the class writer to be used to convert the attributes into
	* byte arrays, with the {@link #write write} method.
	* @param code
	* the bytecode of the method corresponding to these code
	* attributes, or <tt>null</tt> if these attributes are not code
	* attributes.
	* @param len
	* the length of the bytecode of the method corresponding to
	* these code attributes, or <tt>null</tt> if these attributes
	* are not code attributes.
	* @param maxStack
	* the maximum stack size of the method corresponding to these
	* code attributes, or -1 if these attributes are not code
	* attributes.
	* @param maxLocals
	* the maximum number of local variables of the method
	* corresponding to these code attributes, or -1 if these
	* attributes are not code attributes.
	* @return the size of all the attributes in this attribute list. This size
	* includes the size of the attribute headers.
	*/
	final int getSize(final ClassWriter cw, final byte[] code, final int len,
	final int maxStack, final int maxLocals) {
	Attribute attr = this;
	int size = 0;
	while (attr != null) {
	cw.newUTF8(attr.type);
	size += attr.write(cw, code, len, maxStack, maxLocals).length + 6;
	attr = attr.next;
	}
	return size;
	}

	/**
	* Writes all the attributes of this attribute list in the given byte
	* vector.
	*
	* @param cw
	* the class writer to be used to convert the attributes into
	* byte arrays, with the {@link #write write} method.
	* @param code
	* the bytecode of the method corresponding to these code
	* attributes, or <tt>null</tt> if these attributes are not code
	* attributes.
	* @param len
	* the length of the bytecode of the method corresponding to
	* these code attributes, or <tt>null</tt> if these attributes
	* are not code attributes.
	* @param maxStack
	* the maximum stack size of the method corresponding to these
	* code attributes, or -1 if these attributes are not code
	* attributes.
	* @param maxLocals
	* the maximum number of local variables of the method
	* corresponding to these code attributes, or -1 if these
	* attributes are not code attributes.
	* @param out
	* where the attributes must be written.
	*/
	final void put(final ClassWriter cw, final byte[] code, final int len,
	final int maxStack, final int maxLocals, final ByteVector out) {
	Attribute attr = this;
	while (attr != null) {
	ByteVector b = attr.write(cw, code, len, maxStack, maxLocals);
	out.putShort(cw.newUTF8(attr.type)).putInt(b.length);
	out.putByteArray(b.data, 0, b.length);
	attr = attr.next;
	}
	}
	}

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