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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
	*
	* @see StackMap
	* @see StackMapType
	*/
	public final class StackMapEntry implements Node, Cloneable
	{

	private int frameType;
	private int byteCodeOffset;
	private StackMapType[] typesOfLocals;
	private StackMapType[] typesOfStackItems;
	private ConstantPool constantPool;


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

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

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

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


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


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


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


	public void setFrameType( final int f ) {
	if (f >= Const.SAME_FRAME && f <= Const.SAME_FRAME_MAX) {
	byteCodeOffset = f - Const.SAME_FRAME;
	} else if (f >= Const.SAME_LOCALS_1_STACK_ITEM_FRAME &&
	f <= Const.SAME_LOCALS_1_STACK_ITEM_FRAME_MAX) {
	byteCodeOffset = 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 IllegalArgumentException("Invalid StackMap frameType");
	}
	frameType = f;
	}


	public int getFrameType() {
	return frameType;
	}


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

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


	public int getByteCodeOffset() {
	return byteCodeOffset;
	}


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


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


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


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


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


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


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


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


	/**
	* @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.typesOfLocals = new StackMapType[typesOfLocals.length];
	for (int i = 0; i < typesOfLocals.length; i++) {
	e.typesOfLocals[i] = typesOfLocals[i].copy();
	}
	e.typesOfStackItems = new StackMapType[typesOfStackItems.length];
	for (int i = 0; i < typesOfStackItems.length; i++) {
	e.typesOfStackItems[i] = typesOfStackItems[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 ConstantPool getConstantPool() {
	return constantPool;
	}


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

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