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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.tree;

	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;
	import java.util.Map;

	import jdk.internal.org.objectweb.asm.MethodVisitor;
	import jdk.internal.org.objectweb.asm.Opcodes;

	/**
	* A node that represents a stack map frame. These nodes are pseudo instruction
	* nodes in order to be inserted in an instruction list. In fact these nodes
	* must(*) be inserted <i>just before</i> any instruction node <b>i</b> that
	* follows an unconditionnal branch instruction such as GOTO or THROW, that is
	* the target of a jump instruction, or that starts an exception handler block.
	* The stack map frame types must describe the values of the local variables and
	* of the operand stack elements <i>just before</i> <b>i</b> is executed. <br>
	* <br>
	* (*) this is mandatory only for classes whose version is greater than or equal
	* to {@link Opcodes#V1_6 V1_6}.
	*
	* @author Eric Bruneton
	*/
	public class FrameNode extends AbstractInsnNode {

	/**
	* The type of this frame. Must be {@link Opcodes#F_NEW} for expanded
	* frames, or {@link Opcodes#F_FULL}, {@link Opcodes#F_APPEND},
	* {@link Opcodes#F_CHOP}, {@link Opcodes#F_SAME} or
	* {@link Opcodes#F_APPEND}, {@link Opcodes#F_SAME1} for compressed frames.
	*/
	public int type;

	/**
	* The types of the local variables of this stack map frame. Elements of
	* this list can be Integer, String or LabelNode objects (for primitive,
	* reference and uninitialized types respectively - see
	* {@link MethodVisitor}).
	*/
	public List<Object> local;

	/**
	* The types of the operand stack elements of this stack map frame. Elements
	* of this list can be Integer, String or LabelNode objects (for primitive,
	* reference and uninitialized types respectively - see
	* {@link MethodVisitor}).
	*/
	public List<Object> stack;

	private FrameNode() {
	super(-1);
	}

	/**
	* Constructs a new {@link FrameNode}.
	*
	* @param type
	* the type of this frame. Must be {@link Opcodes#F_NEW} for
	* expanded frames, or {@link Opcodes#F_FULL},
	* {@link Opcodes#F_APPEND}, {@link Opcodes#F_CHOP},
	* {@link Opcodes#F_SAME} or {@link Opcodes#F_APPEND},
	* {@link Opcodes#F_SAME1} for compressed frames.
	* @param nLocal
	* number of local variables of this stack map frame.
	* @param local
	* the types of the local variables of this stack map frame.
	* Elements of this list can be Integer, String or LabelNode
	* objects (for primitive, reference and uninitialized types
	* respectively - see {@link MethodVisitor}).
	* @param nStack
	* number of operand stack elements of this stack map frame.
	* @param stack
	* the types of the operand stack elements of this stack map
	* frame. Elements of this list can be Integer, String or
	* LabelNode objects (for primitive, reference and uninitialized
	* types respectively - see {@link MethodVisitor}).
	*/
	public FrameNode(final int type, final int nLocal, final Object[] local,
	final int nStack, final Object[] stack) {
	super(-1);
	this.type = type;
	switch (type) {
	case Opcodes.F_NEW:
	case Opcodes.F_FULL:
	this.local = asList(nLocal, local);
	this.stack = asList(nStack, stack);
	break;
	case Opcodes.F_APPEND:
	this.local = asList(nLocal, local);
	break;
	case Opcodes.F_CHOP:
	this.local = Arrays.asList(new Object[nLocal]);
	break;
	case Opcodes.F_SAME:
	break;
	case Opcodes.F_SAME1:
	this.stack = asList(1, stack);
	break;
	}
	}

	@Override
	public int getType() {
	return FRAME;
	}

	/**
	* Makes the given visitor visit this stack map frame.
	*
	* @param mv
	* a method visitor.
	*/
	@Override
	public void accept(final MethodVisitor mv) {
	switch (type) {
	case Opcodes.F_NEW:
	case Opcodes.F_FULL:
	mv.visitFrame(type, local.size(), asArray(local), stack.size(),
	asArray(stack));
	break;
	case Opcodes.F_APPEND:
	mv.visitFrame(type, local.size(), asArray(local), 0, null);
	break;
	case Opcodes.F_CHOP:
	mv.visitFrame(type, local.size(), null, 0, null);
	break;
	case Opcodes.F_SAME:
	mv.visitFrame(type, 0, null, 0, null);
	break;
	case Opcodes.F_SAME1:
	mv.visitFrame(type, 0, null, 1, asArray(stack));
	break;
	}
	}

	@Override
	public AbstractInsnNode clone(final Map<LabelNode, LabelNode> labels) {
	FrameNode clone = new FrameNode();
	clone.type = type;
	if (local != null) {
	clone.local = new ArrayList<Object>();
	for (int i = 0; i < local.size(); ++i) {
	Object l = local.get(i);
	if (l instanceof LabelNode) {
	l = labels.get(l);
	}
	clone.local.add(l);
	}
	}
	if (stack != null) {
	clone.stack = new ArrayList<Object>();
	for (int i = 0; i < stack.size(); ++i) {
	Object s = stack.get(i);
	if (s instanceof LabelNode) {
	s = labels.get(s);
	}
	clone.stack.add(s);
	}
	}
	return clone;
	}

	// ------------------------------------------------------------------------

	private static List<Object> asList(final int n, final Object[] o) {
	return Arrays.asList(o).subList(0, n);
	}

	private static Object[] asArray(final List<Object> l) {
	Object[] objs = new Object[l.size()];
	for (int i = 0; i < objs.length; ++i) {
	Object o = l.get(i);
	if (o instanceof LabelNode) {
	o = ((LabelNode) o).getLabel();
	}
	objs[i] = o;
	}
	return objs;
	}
	}

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