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	/*
	* Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved.
	* 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.
	*/

	package sun.tools.java;

	import java.io.IOException;
	import java.io.DataInputStream;
	import java.io.DataOutputStream;
	import java.util.Vector;
	import java.util.Hashtable;

	/**
	* This class is used to represent a constant table once
	* it is read from a class file.
	*
	* WARNING: The contents of this source file are not part of any
	* supported API. Code that depends on them does so at its own risk:
	* they are subject to change or removal without notice.
	*/
	public final
	class BinaryConstantPool implements Constants {
	private byte types[];
	private Object cpool[];

	/**
	* Constructor
	*/
	BinaryConstantPool(DataInputStream in) throws IOException {
	// JVM 4.1 ClassFile.constant_pool_count
	types = new byte[in.readUnsignedShort()];
	cpool = new Object[types.length];
	for (int i = 1 ; i < cpool.length ; i++) {
	int j = i;
	// JVM 4.4 cp_info.tag
	switch(types[i] = in.readByte()) {
	case CONSTANT_UTF8:
	cpool[i] = in.readUTF();
	break;

	case CONSTANT_INTEGER:
	cpool[i] = new Integer(in.readInt());
	break;
	case CONSTANT_FLOAT:
	cpool[i] = new Float(in.readFloat());
	break;
	case CONSTANT_LONG:
	cpool[i++] = new Long(in.readLong());
	break;
	case CONSTANT_DOUBLE:
	cpool[i++] = new Double(in.readDouble());
	break;

	case CONSTANT_CLASS:
	case CONSTANT_STRING:
	// JVM 4.4.3 CONSTANT_String_info.string_index
	// or JVM 4.4.1 CONSTANT_Class_info.name_index
	cpool[i] = new Integer(in.readUnsignedShort());
	break;

	case CONSTANT_FIELD:
	case CONSTANT_METHOD:
	case CONSTANT_INTERFACEMETHOD:
	case CONSTANT_NAMEANDTYPE:
	// JVM 4.4.2 CONSTANT_*ref_info.class_index & name_and_type_index
	cpool[i] = new Integer((in.readUnsignedShort() << 16) \| in.readUnsignedShort());
	break;

	case CONSTANT_METHODHANDLE:
	cpool[i] = readBytes(in, 3);
	break;
	case CONSTANT_METHODTYPE:
	cpool[i] = readBytes(in, 2);
	break;
	case CONSTANT_INVOKEDYNAMIC:
	cpool[i] = readBytes(in, 4);
	break;

	case 0:
	default:
	throw new ClassFormatError("invalid constant type: " + (int)types[i]);
	}
	}
	}

	private byte[] readBytes(DataInputStream in, int cnt) throws IOException {
	byte[] b = new byte[cnt];
	in.readFully(b);
	return b;
	}

	/**
	* get a integer
	*/
	public int getInteger(int n) {
	return (n == 0) ? 0 : ((Number)cpool[n]).intValue();
	}

	/**
	* get a value
	*/
	public Object getValue(int n) {
	return (n == 0) ? null : cpool[n];
	}

	/**
	* get a string
	*/
	public String getString(int n) {
	return (n == 0) ? null : (String)cpool[n];
	}

	/**
	* get an identifier
	*/
	public Identifier getIdentifier(int n) {
	return (n == 0) ? null : Identifier.lookup(getString(n));
	}

	/**
	* get class declaration
	*/
	public ClassDeclaration getDeclarationFromName(Environment env, int n) {
	return (n == 0) ? null : env.getClassDeclaration(Identifier.lookup(getString(n).replace('/','.')));
	}

	/**
	* get class declaration
	*/
	public ClassDeclaration getDeclaration(Environment env, int n) {
	return (n == 0) ? null : getDeclarationFromName(env, getInteger(n));
	}

	/**
	* get a type from a type signature
	*/
	public Type getType(int n) {
	return Type.tType(getString(n));
	}

	/**
	* get the type of constant given an index
	*/
	public int getConstantType(int n) {
	return types[n];
	}

	/**
	* get the n-th constant from the constant pool
	*/
	public Object getConstant(int n, Environment env) {
	int constant_type = getConstantType(n);
	switch (constant_type) {
	case CONSTANT_INTEGER:
	case CONSTANT_FLOAT:
	case CONSTANT_LONG:
	case CONSTANT_DOUBLE:
	case CONSTANT_METHODHANDLE:
	case CONSTANT_METHODTYPE:
	case CONSTANT_INVOKEDYNAMIC:
	return getValue(n);

	case CONSTANT_CLASS:
	return getDeclaration(env, n);

	case CONSTANT_STRING:
	return getString(getInteger(n));

	case CONSTANT_FIELD:
	case CONSTANT_METHOD:
	case CONSTANT_INTERFACEMETHOD:
	try {
	int key = getInteger(n);
	ClassDefinition clazz =
	getDeclaration(env, key >> 16).getClassDefinition(env);
	int name_and_type = getInteger(key & 0xFFFF);
	Identifier id = getIdentifier(name_and_type >> 16);
	Type type = getType(name_and_type & 0xFFFF);

	for (MemberDefinition field = clazz.getFirstMatch(id);
	field != null;
	field = field.getNextMatch()) {
	Type field_type = field.getType();
	if ((constant_type == CONSTANT_FIELD)
	? (field_type == type)
	: (field_type.equalArguments(type)))
	return field;
	}
	} catch (ClassNotFound e) {
	}
	return null;

	default:
	throw new ClassFormatError("invalid constant type: " +
	constant_type);
	}
	}


	/**
	* Get a list of dependencies, ie: all the classes referenced in this
	* constant pool.
	*/
	public Vector getDependencies(Environment env) {
	Vector v = new Vector();
	for (int i = 1 ; i < cpool.length ; i++) {
	switch(types[i]) {
	case CONSTANT_CLASS:
	v.addElement(getDeclarationFromName(env, getInteger(i)));
	break;
	}
	}
	return v;
	}

	Hashtable indexHashObject, indexHashAscii;
	Vector MoreStuff;

	/**
	* Find the index of an Object in the constant pool
	*/
	public int indexObject(Object obj, Environment env) {
	if (indexHashObject == null)
	createIndexHash(env);
	Integer result = (Integer)indexHashObject.get(obj);
	if (result == null)
	throw new IndexOutOfBoundsException("Cannot find object " + obj + " of type " +
	obj.getClass() + " in constant pool");
	return result.intValue();
	}

	/**
	* Find the index of an ascii string in the constant pool. If it's not in
	* the constant pool, then add it at the end.
	*/
	public int indexString(String string, Environment env) {
	if (indexHashObject == null)
	createIndexHash(env);
	Integer result = (Integer)indexHashAscii.get(string);
	if (result == null) {
	if (MoreStuff == null) MoreStuff = new Vector();
	result = new Integer(cpool.length + MoreStuff.size());
	MoreStuff.addElement(string);
	indexHashAscii.put(string, result);
	}
	return result.intValue();
	}

	/**
	* Create a hash table of all the items in the constant pool that could
	* possibly be referenced from the outside.
	*/

	public void createIndexHash(Environment env) {
	indexHashObject = new Hashtable();
	indexHashAscii = new Hashtable();
	for (int i = 1; i < cpool.length; i++) {
	if (types[i] == CONSTANT_UTF8) {
	indexHashAscii.put(cpool[i], new Integer(i));
	} else {
	try {
	indexHashObject.put(getConstant(i, env), new Integer(i));
	} catch (ClassFormatError e) { }
	}
	}
	}


	/**
	* Write out the contents of the constant pool, including any additions
	* that have been added.
	*/
	public void write(DataOutputStream out, Environment env) throws IOException {
	int length = cpool.length;
	if (MoreStuff != null)
	length += MoreStuff.size();
	out.writeShort(length);
	for (int i = 1 ; i < cpool.length; i++) {
	int type = types[i];
	Object x = cpool[i];
	out.writeByte(type);
	switch (type) {
	case CONSTANT_UTF8:
	out.writeUTF((String) x);
	break;
	case CONSTANT_INTEGER:
	out.writeInt(((Number)x).intValue());
	break;
	case CONSTANT_FLOAT:
	out.writeFloat(((Number)x).floatValue());
	break;
	case CONSTANT_LONG:
	out.writeLong(((Number)x).longValue());
	i++;
	break;
	case CONSTANT_DOUBLE:
	out.writeDouble(((Number)x).doubleValue());
	i++;
	break;
	case CONSTANT_CLASS:
	case CONSTANT_STRING:
	out.writeShort(((Number)x).intValue());
	break;
	case CONSTANT_FIELD:
	case CONSTANT_METHOD:
	case CONSTANT_INTERFACEMETHOD:
	case CONSTANT_NAMEANDTYPE: {
	int value = ((Number)x).intValue();
	out.writeShort(value >> 16);
	out.writeShort(value & 0xFFFF);
	break;
	}
	case CONSTANT_METHODHANDLE:
	case CONSTANT_METHODTYPE:
	case CONSTANT_INVOKEDYNAMIC:
	out.write((byte[])x, 0, ((byte[])x).length);
	break;
	default:
	throw new ClassFormatError("invalid constant type: "
	+ (int)types[i]);
	}
	}
	for (int i = cpool.length; i < length; i++) {
	String string = (String)(MoreStuff.elementAt(i - cpool.length));
	out.writeByte(CONSTANT_UTF8);
	out.writeUTF(string);
	}
	}

	}

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