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	/*
	* reserved comment block
	* DO NOT REMOVE OR ALTER!
	*/
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.sun.org.apache.bcel.internal.classfile;

	import java.io.DataInput;
	import java.io.DataOutputStream;
	import java.io.IOException;
	import com.sun.org.apache.bcel.internal.Const;

	/**
	* This class represents a stack map entry recording the types of
	* local variables and the the of stack items at a given byte code offset.
	* See CLDC specification 5.3.1.2
	*
	* @version $Id: StackMapEntry.java 1750029 2016-06-23 22:14:38Z sebb $
	* @see StackMap
	* @see StackMapType
	*/
	public final class StackMapEntry implements Node, Cloneable
	{

	private int frame_type;
	private int byte_code_offset;
	private StackMapType[] types_of_locals;
	private StackMapType[] types_of_stack_items;
	private ConstantPool constant_pool;


	/**
	* Construct object from input stream.
	*
	* @param input Input stream
	* @throws IOException
	*/
	StackMapEntry(final DataInput input, final ConstantPool constant_pool) throws IOException {
	this(input.readByte() & 0xFF, -1, null, null, constant_pool);

	if (frame_type >= Const.SAME_FRAME && frame_type <= Const.SAME_FRAME_MAX) {
	byte_code_offset = frame_type - Const.SAME_FRAME;
	} else if (frame_type >= Const.SAME_LOCALS_1_STACK_ITEM_FRAME &&
	frame_type <= Const.SAME_LOCALS_1_STACK_ITEM_FRAME_MAX) {
	byte_code_offset = frame_type - Const.SAME_LOCALS_1_STACK_ITEM_FRAME;
	types_of_stack_items = new StackMapType[1];
	types_of_stack_items[0] = new StackMapType(input, constant_pool);
	} else if (frame_type == Const.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) {
	byte_code_offset = input.readShort();
	types_of_stack_items = new StackMapType[1];
	types_of_stack_items[0] = new StackMapType(input, constant_pool);
	} else if (frame_type >= Const.CHOP_FRAME && frame_type <= Const.CHOP_FRAME_MAX) {
	byte_code_offset = input.readShort();
	} else if (frame_type == Const.SAME_FRAME_EXTENDED) {
	byte_code_offset = input.readShort();
	} else if (frame_type >= Const.APPEND_FRAME && frame_type <= Const.APPEND_FRAME_MAX) {
	byte_code_offset = input.readShort();
	final int number_of_locals = frame_type - 251;
	types_of_locals = new StackMapType[number_of_locals];
	for (int i = 0; i < number_of_locals; i++) {
	types_of_locals[i] = new StackMapType(input, constant_pool);
	}
	} else if (frame_type == Const.FULL_FRAME) {
	byte_code_offset = input.readShort();
	final int number_of_locals = input.readShort();
	types_of_locals = new StackMapType[number_of_locals];
	for (int i = 0; i < number_of_locals; i++) {
	types_of_locals[i] = new StackMapType(input, constant_pool);
	}
	final int number_of_stack_items = input.readShort();
	types_of_stack_items = new StackMapType[number_of_stack_items];
	for (int i = 0; i < number_of_stack_items; i++) {
	types_of_stack_items[i] = new StackMapType(input, constant_pool);
	}
	} else {
	/* Can't happen */
	throw new ClassFormatException ("Invalid frame type found while parsing stack map table: " + frame_type);
	}
	}

	/**
	* DO NOT USE
	*
	* @param byte_code_offset
	* @param number_of_locals NOT USED
	* @param types_of_locals array of {@link StackMapType}s of locals
	* @param number_of_stack_items NOT USED
	* @param types_of_stack_items array ot {@link StackMapType}s of stack items
	* @param constant_pool the constant pool
	* @deprecated Since 6.0, use {@link #StackMapEntry(int, int, StackMapType[], StackMapType[], ConstantPool)}
	* instead
	*/
	@java.lang.Deprecated
	public StackMapEntry(final int byte_code_offset, final int number_of_locals,
	final StackMapType[] types_of_locals, final int number_of_stack_items,
	final StackMapType[] types_of_stack_items, final ConstantPool constant_pool) {
	this.byte_code_offset = byte_code_offset;
	this.types_of_locals = types_of_locals != null ? types_of_locals : new StackMapType[0];
	this.types_of_stack_items = types_of_stack_items != null ? types_of_stack_items : new StackMapType[0];
	this.constant_pool = constant_pool;
	}

	/**
	* Create an instance
	*
	* @param tag the frame_type to use
	* @param byte_code_offset
	* @param types_of_locals array of {@link StackMapType}s of locals
	* @param types_of_stack_items array ot {@link StackMapType}s of stack items
	* @param constant_pool the constant pool
	*/
	public StackMapEntry(final int tag, final int byte_code_offset,
	final StackMapType[] types_of_locals,
	final StackMapType[] types_of_stack_items, final ConstantPool constant_pool) {
	this.frame_type = tag;
	this.byte_code_offset = byte_code_offset;
	this.types_of_locals = types_of_locals != null ? types_of_locals : new StackMapType[0];
	this.types_of_stack_items = types_of_stack_items != null ? types_of_stack_items : new StackMapType[0];
	this.constant_pool = constant_pool;
	}


	/**
	* Dump stack map entry
	*
	* @param file Output file stream
	* @throws IOException
	*/
	public final void dump( final DataOutputStream file ) throws IOException {
	file.write(frame_type);
	if (frame_type >= Const.SAME_FRAME && frame_type <= Const.SAME_FRAME_MAX) {
	// nothing to be done
	} else if (frame_type >= Const.SAME_LOCALS_1_STACK_ITEM_FRAME &&
	frame_type <= Const.SAME_LOCALS_1_STACK_ITEM_FRAME_MAX) {
	types_of_stack_items[0].dump(file);
	} else if (frame_type == Const.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) {
	file.writeShort(byte_code_offset);
	types_of_stack_items[0].dump(file);
	} else if (frame_type >= Const.CHOP_FRAME && frame_type <= Const.CHOP_FRAME_MAX) {
	file.writeShort(byte_code_offset);
	} else if (frame_type == Const.SAME_FRAME_EXTENDED) {
	file.writeShort(byte_code_offset);
	} else if (frame_type >= Const.APPEND_FRAME && frame_type <= Const.APPEND_FRAME_MAX) {
	file.writeShort(byte_code_offset);
	for (final StackMapType type : types_of_locals) {
	type.dump(file);
	}
	} else if (frame_type == Const.FULL_FRAME) {
	file.writeShort(byte_code_offset);
	file.writeShort(types_of_locals.length);
	for (final StackMapType type : types_of_locals) {
	type.dump(file);
	}
	file.writeShort(types_of_stack_items.length);
	for (final StackMapType type : types_of_stack_items) {
	type.dump(file);
	}
	} else {
	/* Can't happen */
	throw new ClassFormatException ("Invalid Stack map table tag: " + frame_type);
	}
	}


	/**
	* @return String representation.
	*/
	@Override
	public final String toString() {
	final StringBuilder buf = new StringBuilder(64);
	buf.append("(");
	if (frame_type >= Const.SAME_FRAME && frame_type <= Const.SAME_FRAME_MAX) {
	buf.append("SAME");
	} else if (frame_type >= Const.SAME_LOCALS_1_STACK_ITEM_FRAME &&
	frame_type <= Const.SAME_LOCALS_1_STACK_ITEM_FRAME_MAX) {
	buf.append("SAME_LOCALS_1_STACK");
	} else if (frame_type == Const.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) {
	buf.append("SAME_LOCALS_1_STACK_EXTENDED");
	} else if (frame_type >= Const.CHOP_FRAME && frame_type <= Const.CHOP_FRAME_MAX) {
	buf.append("CHOP ").append(String.valueOf(251-frame_type));
	} else if (frame_type == Const.SAME_FRAME_EXTENDED) {
	buf.append("SAME_EXTENDED");
	} else if (frame_type >= Const.APPEND_FRAME && frame_type <= Const.APPEND_FRAME_MAX) {
	buf.append("APPEND ").append(String.valueOf(frame_type-251));
	} else if (frame_type == Const.FULL_FRAME) {
	buf.append("FULL");
	} else {
	buf.append("UNKNOWN (").append(frame_type).append(")");
	}
	buf.append(", offset delta=").append(byte_code_offset);
	if (types_of_locals.length > 0) {
	buf.append(", locals={");
	for (int i = 0; i < types_of_locals.length; i++) {
	buf.append(types_of_locals[i]);
	if (i < types_of_locals.length - 1) {
	buf.append(", ");
	}
	}
	buf.append("}");
	}
	if (types_of_stack_items.length > 0) {
	buf.append(", stack items={");
	for (int i = 0; i < types_of_stack_items.length; i++) {
	buf.append(types_of_stack_items[i]);
	if (i < types_of_stack_items.length - 1) {
	buf.append(", ");
	}
	}
	buf.append("}");
	}
	buf.append(")");
	return buf.toString();
	}


	/**
	* Calculate stack map entry size
	*
	*/
	int getMapEntrySize() {
	if (frame_type >= Const.SAME_FRAME && frame_type <= Const.SAME_FRAME_MAX) {
	return 1;
	} else if (frame_type >= Const.SAME_LOCALS_1_STACK_ITEM_FRAME &&
	frame_type <= Const.SAME_LOCALS_1_STACK_ITEM_FRAME_MAX) {
	return 1 + (types_of_stack_items[0].hasIndex() ? 3 : 1);
	} else if (frame_type == Const.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) {
	return 3 + (types_of_stack_items[0].hasIndex() ? 3 : 1);
	} else if (frame_type >= Const.CHOP_FRAME && frame_type <= Const.CHOP_FRAME_MAX) {
	return 3;
	} else if (frame_type == Const.SAME_FRAME_EXTENDED) {
	return 3;
	} else if (frame_type >= Const.APPEND_FRAME && frame_type <= Const.APPEND_FRAME_MAX) {
	int len = 3;
	for (final StackMapType types_of_local : types_of_locals) {
	len += types_of_local.hasIndex() ? 3 : 1;
	}
	return len;
	} else if (frame_type == Const.FULL_FRAME) {
	int len = 7;
	for (final StackMapType types_of_local : types_of_locals) {
	len += types_of_local.hasIndex() ? 3 : 1;
	}
	for (final StackMapType types_of_stack_item : types_of_stack_items) {
	len += types_of_stack_item.hasIndex() ? 3 : 1;
	}
	return len;
	} else {
	throw new RuntimeException("Invalid StackMap frame_type: " + frame_type);
	}
	}


	public void setFrameType( final int f ) {
	if (f >= Const.SAME_FRAME && f <= Const.SAME_FRAME_MAX) {
	byte_code_offset = f - Const.SAME_FRAME;
	} else if (f >= Const.SAME_LOCALS_1_STACK_ITEM_FRAME &&
	f <= Const.SAME_LOCALS_1_STACK_ITEM_FRAME_MAX) {
	byte_code_offset = f - Const.SAME_LOCALS_1_STACK_ITEM_FRAME;
	} else if (f == Const.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (f >= Const.CHOP_FRAME && f <= Const.CHOP_FRAME_MAX) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (f == Const.SAME_FRAME_EXTENDED) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (f >= Const.APPEND_FRAME && f <= Const.APPEND_FRAME_MAX) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (f == Const.FULL_FRAME) { // CHECKSTYLE IGNORE EmptyBlock
	} else {
	throw new RuntimeException("Invalid StackMap frame_type");
	}
	frame_type = f;
	}


	public int getFrameType() {
	return frame_type;
	}


	public void setByteCodeOffset( final int new_offset ) {
	if (new_offset < 0 \|\| new_offset > 32767) {
	throw new RuntimeException("Invalid StackMap offset: " + new_offset);
	}

	if (frame_type >= Const.SAME_FRAME &&
	frame_type <= Const.SAME_FRAME_MAX) {
	if (new_offset > Const.SAME_FRAME_MAX) {
	frame_type = Const.SAME_FRAME_EXTENDED;
	} else {
	frame_type = new_offset;
	}
	} else if (frame_type >= Const.SAME_LOCALS_1_STACK_ITEM_FRAME &&
	frame_type <= Const.SAME_LOCALS_1_STACK_ITEM_FRAME_MAX) {
	if (new_offset > Const.SAME_FRAME_MAX) {
	frame_type = Const.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED;
	} else {
	frame_type = Const.SAME_LOCALS_1_STACK_ITEM_FRAME + new_offset;
	}
	} else if (frame_type == Const.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (frame_type >= Const.CHOP_FRAME &&
	frame_type <= Const.CHOP_FRAME_MAX) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (frame_type == Const.SAME_FRAME_EXTENDED) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (frame_type >= Const.APPEND_FRAME &&
	frame_type <= Const.APPEND_FRAME_MAX) { // CHECKSTYLE IGNORE EmptyBlock
	} else if (frame_type == Const.FULL_FRAME) { // CHECKSTYLE IGNORE EmptyBlock
	} else {
	throw new RuntimeException("Invalid StackMap frame_type: " + frame_type);
	}
	byte_code_offset = new_offset;
	}


	/**
	* Update the distance (as an offset delta) from this StackMap
	* entry to the next. Note that this might cause the the
	* frame type to change. Note also that delta may be negative.
	*
	* @param delta offset delta
	*/
	public void updateByteCodeOffset(final int delta) {
	setByteCodeOffset(byte_code_offset + delta);
	}


	public int getByteCodeOffset() {
	return byte_code_offset;
	}


	/**
	*
	* @deprecated since 6.0
	*/
	@java.lang.Deprecated
	public void setNumberOfLocals( final int n ) { // TODO unused
	}


	public int getNumberOfLocals() {
	return types_of_locals.length;
	}


	public void setTypesOfLocals( final StackMapType[] types ) {
	types_of_locals = types != null ? types : new StackMapType[0];
	}


	public StackMapType[] getTypesOfLocals() {
	return types_of_locals;
	}


	/**
	*
	* @deprecated since 6.0
	*/
	@java.lang.Deprecated
	public void setNumberOfStackItems( final int n ) { // TODO unused
	}


	public int getNumberOfStackItems() {
	return types_of_stack_items.length;
	}


	public void setTypesOfStackItems( final StackMapType[] types ) {
	types_of_stack_items = types != null ? types : new StackMapType[0];
	}


	public StackMapType[] getTypesOfStackItems() {
	return types_of_stack_items;
	}


	/**
	* @return deep copy of this object
	*/
	public StackMapEntry copy() {
	StackMapEntry e;
	try {
	e = (StackMapEntry) clone();
	} catch (final CloneNotSupportedException ex) {
	throw new Error("Clone Not Supported");
	}

	e.types_of_locals = new StackMapType[types_of_locals.length];
	for (int i = 0; i < types_of_locals.length; i++) {
	e.types_of_locals[i] = types_of_locals[i].copy();
	}
	e.types_of_stack_items = new StackMapType[types_of_stack_items.length];
	for (int i = 0; i < types_of_stack_items.length; i++) {
	e.types_of_stack_items[i] = types_of_stack_items[i].copy();
	}
	return e;
	}


	/**
	* Called by objects that are traversing the nodes of the tree implicitely
	* defined by the contents of a Java class. I.e., the hierarchy of methods,
	* fields, attributes, etc. spawns a tree of objects.
	*
	* @param v Visitor object
	*/
	@Override
	public void accept( final Visitor v ) {
	v.visitStackMapEntry(this);
	}


	/**
	* @return Constant pool used by this object.
	*/
	public final ConstantPool getConstantPool() {
	return constant_pool;
	}


	/**
	* @param constant_pool Constant pool to be used for this object.
	*/
	public final void setConstantPool( final ConstantPool constant_pool ) {
	this.constant_pool = constant_pool;
	}
	}

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