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	/*
	* Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
	*/
	/*
	* 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.xpath.internal.objects;

	import com.sun.org.apache.xalan.internal.res.XSLMessages;
	import com.sun.org.apache.xml.internal.dtm.DTM;
	import com.sun.org.apache.xml.internal.dtm.DTMIterator;
	import com.sun.org.apache.xml.internal.utils.QName;
	import com.sun.org.apache.xml.internal.utils.XMLString;
	import com.sun.org.apache.xpath.internal.Expression;
	import com.sun.org.apache.xpath.internal.ExpressionOwner;
	import com.sun.org.apache.xpath.internal.NodeSetDTM;
	import com.sun.org.apache.xpath.internal.XPathContext;
	import com.sun.org.apache.xpath.internal.XPathException;
	import com.sun.org.apache.xpath.internal.XPathVisitor;
	import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;
	import java.io.Serializable;
	import java.util.List;
	import org.w3c.dom.DocumentFragment;
	import org.w3c.dom.NodeList;
	import org.w3c.dom.traversal.NodeIterator;

	/**
	* This class represents an XPath object, and is capable of
	* converting the object to various types, such as a string.
	* This class acts as the base class to other XPath type objects,
	* such as XString, and provides polymorphic casting capabilities.
	* @xsl.usage general
	* @LastModified: Oct 2017
	*/
	public class XObject extends Expression implements Serializable, Cloneable
	{
	static final long serialVersionUID = -821887098985662951L;

	/**
	* The java object which this object wraps.
	* @serial
	*/
	protected Object m_obj; // This may be NULL!!!

	/**
	* Create an XObject.
	*/
	public XObject(){}

	/**
	* Create an XObject.
	*
	* @param obj Can be any object, should be a specific type
	* for derived classes, or null.
	*/
	public XObject(Object obj)
	{
	setObject(obj);
	}

	protected void setObject(Object obj) {
	m_obj = obj;
	}

	/**
	* For support of literal objects in xpaths.
	*
	* @param xctxt The XPath execution context.
	*
	* @return This object.
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public XObject execute(XPathContext xctxt)
	throws javax.xml.transform.TransformerException
	{
	return this;
	}

	/**
	* Specify if it's OK for detach to release the iterator for reuse.
	* This function should be called with a value of false for objects that are
	* stored in variables.
	* Calling this with a value of false on a XNodeSet will cause the nodeset
	* to be cached.
	*
	* @param allowRelease true if it is OK for detach to release this iterator
	* for pooling.
	*/
	public void allowDetachToRelease(boolean allowRelease){}

	/**
	* Detaches the <code>DTMIterator</code> from the set which it iterated
	* over, releasing any computational resources and placing the iterator
	* in the INVALID state. After <code>detach</code> has been invoked,
	* calls to <code>nextNode</code> or <code>previousNode</code> will
	* raise a runtime exception.
	*/
	public void detach(){}

	/**
	* Forces the object to release it's resources. This is more harsh than
	* detach().
	*/
	public void destruct()
	{

	if (null != m_obj)
	{
	allowDetachToRelease(true);
	detach();

	setObject(null);
	}
	}

	/**
	* Reset for fresh reuse.
	*/
	public void reset()
	{
	}

	/**
	* Directly call the
	* characters method on the passed ContentHandler for the
	* string-value. Multiple calls to the
	* ContentHandler's characters methods may well occur for a single call to
	* this method.
	*
	* @param ch A non-null reference to a ContentHandler.
	*
	* @throws org.xml.sax.SAXException
	*/
	public void dispatchCharactersEvents(org.xml.sax.ContentHandler ch)
	throws org.xml.sax.SAXException
	{
	xstr().dispatchCharactersEvents(ch);
	}

	/**
	* Create the right XObject based on the type of the object passed. This
	* function can not make an XObject that exposes DOM Nodes, NodeLists, and
	* NodeIterators to the XSLT stylesheet as node-sets.
	*
	* @param val The java object which this object will wrap.
	*
	* @return the right XObject based on the type of the object passed.
	*/
	static public XObject create(Object val)
	{
	return XObjectFactory.create(val);
	}

	/**
	* Create the right XObject based on the type of the object passed.
	* This function <emph>can</emph> make an XObject that exposes DOM Nodes, NodeLists, and
	* NodeIterators to the XSLT stylesheet as node-sets.
	*
	* @param val The java object which this object will wrap.
	* @param xctxt The XPath context.
	*
	* @return the right XObject based on the type of the object passed.
	*/
	static public XObject create(Object val, XPathContext xctxt)
	{
	return XObjectFactory.create(val, xctxt);
	}

	/** Constant for NULL object type */
	public static final int CLASS_NULL = -1;

	/** Constant for UNKNOWN object type */
	public static final int CLASS_UNKNOWN = 0;

	/** Constant for BOOLEAN object type */
	public static final int CLASS_BOOLEAN = 1;

	/** Constant for NUMBER object type */
	public static final int CLASS_NUMBER = 2;

	/** Constant for STRING object type */
	public static final int CLASS_STRING = 3;

	/** Constant for NODESET object type */
	public static final int CLASS_NODESET = 4;

	/** Constant for RESULT TREE FRAGMENT object type */
	public static final int CLASS_RTREEFRAG = 5;

	/** Represents an unresolved variable type as an integer. */
	public static final int CLASS_UNRESOLVEDVARIABLE = 600;

	/**
	* Tell what kind of class this is.
	*
	* @return CLASS_UNKNOWN
	*/
	public int getType()
	{
	return CLASS_UNKNOWN;
	}

	/**
	* Given a request type, return the equivalent string.
	* For diagnostic purposes.
	*
	* @return type string "#UNKNOWN" + object class name
	*/
	public String getTypeString()
	{
	return "#UNKNOWN (" + object().getClass().getName() + ")";
	}

	/**
	* Cast result object to a number. Always issues an error.
	*
	* @return 0.0
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public double num() throws javax.xml.transform.TransformerException
	{

	error(XPATHErrorResources.ER_CANT_CONVERT_TO_NUMBER,
	new Object[]{ getTypeString() }); //"Can not convert "+getTypeString()+" to a number");

	return 0.0;
	}

	/**
	* Cast result object to a number, but allow side effects, such as the
	* incrementing of an iterator.
	*
	* @return numeric value of the string conversion from the
	* next node in the NodeSetDTM, or NAN if no node was found
	*/
	public double numWithSideEffects() throws javax.xml.transform.TransformerException
	{
	return num();
	}

	/**
	* Cast result object to a boolean. Always issues an error.
	*
	* @return false
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public boolean bool() throws javax.xml.transform.TransformerException
	{

	error(XPATHErrorResources.ER_CANT_CONVERT_TO_NUMBER,
	new Object[]{ getTypeString() }); //"Can not convert "+getTypeString()+" to a number");

	return false;
	}

	/**
	* Cast result object to a boolean, but allow side effects, such as the
	* incrementing of an iterator.
	*
	* @return True if there is a next node in the nodeset
	*/
	public boolean boolWithSideEffects() throws javax.xml.transform.TransformerException
	{
	return bool();
	}


	/**
	* Cast result object to a string.
	*
	* @return The string this wraps or the empty string if null
	*/
	public XMLString xstr()
	{
	return XMLStringFactoryImpl.getFactory().newstr(str());
	}

	/**
	* Cast result object to a string.
	*
	* @return The object as a string
	*/
	public String str()
	{
	return (m_obj != null) ? m_obj.toString() : "";
	}

	/**
	* Return the string representation of the object
	*
	*
	* @return the string representation of the object
	*/
	public String toString()
	{
	return str();
	}

	/**
	* Cast result object to a result tree fragment.
	*
	* @param support XPath context to use for the conversion
	*
	* @return the objec as a result tree fragment.
	*/
	public int rtf(XPathContext support)
	{

	int result = rtf();

	if (DTM.NULL == result)
	{
	DTM frag = support.createDocumentFragment();

	// %OPT%
	frag.appendTextChild(str());

	result = frag.getDocument();
	}

	return result;
	}

	/**
	* Cast result object to a result tree fragment.
	*
	* @param support XPath context to use for the conversion
	*
	* @return the objec as a result tree fragment.
	*/
	public DocumentFragment rtree(XPathContext support)
	{
	DocumentFragment docFrag = null;
	int result = rtf();

	if (DTM.NULL == result)
	{
	DTM frag = support.createDocumentFragment();

	// %OPT%
	frag.appendTextChild(str());

	docFrag = (DocumentFragment)frag.getNode(frag.getDocument());
	}
	else
	{
	DTM frag = support.getDTM(result);
	docFrag = (DocumentFragment)frag.getNode(frag.getDocument());
	}

	return docFrag;
	}


	/**
	* For functions to override.
	*
	* @return null
	*/
	public DocumentFragment rtree()
	{
	return null;
	}

	/**
	* For functions to override.
	*
	* @return null
	*/
	public int rtf()
	{
	return DTM.NULL;
	}

	/**
	* Return a java object that's closest to the representation
	* that should be handed to an extension.
	*
	* @return The object that this class wraps
	*/
	public Object object()
	{
	return m_obj;
	}

	/**
	* Cast result object to a nodelist. Always issues an error.
	*
	* @return null
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public DTMIterator iter() throws javax.xml.transform.TransformerException
	{

	error(XPATHErrorResources.ER_CANT_CONVERT_TO_NODELIST,
	new Object[]{ getTypeString() }); //"Can not convert "+getTypeString()+" to a NodeList!");

	return null;
	}

	/**
	* Get a fresh copy of the object. For use with variables.
	*
	* @return This object, unless overridden by subclass.
	*/
	public XObject getFresh()
	{
	return this;
	}


	/**
	* Cast result object to a nodelist. Always issues an error.
	*
	* @return null
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public NodeIterator nodeset() throws javax.xml.transform.TransformerException
	{

	error(XPATHErrorResources.ER_CANT_CONVERT_TO_NODELIST,
	new Object[]{ getTypeString() }); //"Can not convert "+getTypeString()+" to a NodeList!");

	return null;
	}

	/**
	* Cast result object to a nodelist. Always issues an error.
	*
	* @return null
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public NodeList nodelist() throws javax.xml.transform.TransformerException
	{

	error(XPATHErrorResources.ER_CANT_CONVERT_TO_NODELIST,
	new Object[]{ getTypeString() }); //"Can not convert "+getTypeString()+" to a NodeList!");

	return null;
	}


	/**
	* Cast result object to a nodelist. Always issues an error.
	*
	* @return The object as a NodeSetDTM.
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public NodeSetDTM mutableNodeset()
	throws javax.xml.transform.TransformerException
	{

	error(XPATHErrorResources.ER_CANT_CONVERT_TO_MUTABLENODELIST,
	new Object[]{ getTypeString() }); //"Can not convert "+getTypeString()+" to a NodeSetDTM!");

	return (NodeSetDTM) m_obj;
	}

	/**
	* Cast object to type t.
	*
	* @param t Type of object to cast this to
	* @param support XPath context to use for the conversion
	*
	* @return This object as the given type t
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public Object castToType(int t, XPathContext support)
	throws javax.xml.transform.TransformerException
	{

	Object result;

	switch (t)
	{
	case CLASS_STRING :
	result = str();
	break;
	case CLASS_NUMBER :
	result = num();
	break;
	case CLASS_NODESET :
	result = iter();
	break;
	case CLASS_BOOLEAN :
	result = bool();
	break;
	case CLASS_UNKNOWN :
	result = m_obj;
	break;

	// %TBD% What to do here?
	// case CLASS_RTREEFRAG :
	// result = rtree(support);
	// break;
	default :
	error(XPATHErrorResources.ER_CANT_CONVERT_TO_TYPE,
	new Object[]{ getTypeString(),
	Integer.toString(t) }); //"Can not convert "+getTypeString()+" to a type#"+t);

	result = null;
	}

	return result;
	}

	/**
	* Tell if one object is less than the other.
	*
	* @param obj2 Object to compare this to
	*
	* @return True if this object is less than the given object
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public boolean lessThan(XObject obj2)
	throws javax.xml.transform.TransformerException
	{

	// In order to handle the 'all' semantics of
	// nodeset comparisons, we always call the
	// nodeset function. Because the arguments
	// are backwards, we call the opposite comparison
	// function.
	if (obj2.getType() == XObject.CLASS_NODESET)
	return obj2.greaterThan(this);

	return this.num() < obj2.num();
	}

	/**
	* Tell if one object is less than or equal to the other.
	*
	* @param obj2 Object to compare this to
	*
	* @return True if this object is less than or equal to the given object
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public boolean lessThanOrEqual(XObject obj2)
	throws javax.xml.transform.TransformerException
	{

	// In order to handle the 'all' semantics of
	// nodeset comparisons, we always call the
	// nodeset function. Because the arguments
	// are backwards, we call the opposite comparison
	// function.
	if (obj2.getType() == XObject.CLASS_NODESET)
	return obj2.greaterThanOrEqual(this);

	return this.num() <= obj2.num();
	}

	/**
	* Tell if one object is greater than the other.
	*
	* @param obj2 Object to compare this to
	*
	* @return True if this object is greater than the given object
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public boolean greaterThan(XObject obj2)
	throws javax.xml.transform.TransformerException
	{

	// In order to handle the 'all' semantics of
	// nodeset comparisons, we always call the
	// nodeset function. Because the arguments
	// are backwards, we call the opposite comparison
	// function.
	if (obj2.getType() == XObject.CLASS_NODESET)
	return obj2.lessThan(this);

	return this.num() > obj2.num();
	}

	/**
	* Tell if one object is greater than or equal to the other.
	*
	* @param obj2 Object to compare this to
	*
	* @return True if this object is greater than or equal to the given object
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public boolean greaterThanOrEqual(XObject obj2)
	throws javax.xml.transform.TransformerException
	{

	// In order to handle the 'all' semantics of
	// nodeset comparisons, we always call the
	// nodeset function. Because the arguments
	// are backwards, we call the opposite comparison
	// function.
	if (obj2.getType() == XObject.CLASS_NODESET)
	return obj2.lessThanOrEqual(this);

	return this.num() >= obj2.num();
	}

	/**
	* Tell if two objects are functionally equal.
	*
	* @param obj2 Object to compare this to
	*
	* @return True if this object is equal to the given object
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public boolean equals(XObject obj2)
	{

	// In order to handle the 'all' semantics of
	// nodeset comparisons, we always call the
	// nodeset function.
	if (obj2.getType() == XObject.CLASS_NODESET)
	return obj2.equals(this);

	if (null != m_obj)
	{
	return m_obj.equals(obj2.m_obj);
	}
	else
	{
	return obj2.m_obj == null;
	}
	}

	/**
	* Tell if two objects are functionally not equal.
	*
	* @param obj2 Object to compare this to
	*
	* @return True if this object is not equal to the given object
	*
	* @throws javax.xml.transform.TransformerException
	*/
	public boolean notEquals(XObject obj2)
	throws javax.xml.transform.TransformerException
	{

	// In order to handle the 'all' semantics of
	// nodeset comparisons, we always call the
	// nodeset function.
	if (obj2.getType() == XObject.CLASS_NODESET)
	return obj2.notEquals(this);

	return !equals(obj2);
	}

	/**
	* Tell the user of an error, and probably throw an
	* exception.
	*
	* @param msg Error message to issue
	*
	* @throws javax.xml.transform.TransformerException
	*/
	protected void error(String msg)
	throws javax.xml.transform.TransformerException
	{
	error(msg, null);
	}

	/**
	* Tell the user of an error, and probably throw an
	* exception.
	*
	* @param msg Error message to issue
	* @param args Arguments to use in the message
	*
	* @throws javax.xml.transform.TransformerException
	*/
	protected void error(String msg, Object[] args)
	throws javax.xml.transform.TransformerException
	{

	String fmsg = XSLMessages.createXPATHMessage(msg, args);

	// boolean shouldThrow = support.problem(m_support.XPATHPROCESSOR,
	// m_support.ERROR,
	// null,
	// null, fmsg, 0, 0);
	// if(shouldThrow)
	{
	throw new XPathException(fmsg, this);
	}
	}


	/**
	* XObjects should not normally need to fix up variables.
	*/
	public void fixupVariables(List<QName> vars, int globalsSize)
	{
	// no-op
	}


	/**
	* Cast result object to a string.
	*
	*
	* NEEDSDOC @param fsb
	* @return The string this wraps or the empty string if null
	*/
	public void appendToFsb(com.sun.org.apache.xml.internal.utils.FastStringBuffer fsb)
	{
	fsb.append(str());
	}

	/**
	* @see com.sun.org.apache.xpath.internal.XPathVisitable#callVisitors(ExpressionOwner, XPathVisitor)
	*/
	public void callVisitors(ExpressionOwner owner, XPathVisitor visitor)
	{
	assertion(false, "callVisitors should not be called for this object!!!");
	}
	/**
	* @see Expression#deepEquals(Expression)
	*/
	public boolean deepEquals(Expression expr)
	{
	if(!isSameClass(expr))
	return false;

	// If equals at the expression level calls deepEquals, I think we're
	// still safe from infinite recursion since this object overrides
	// equals. I hope.
	if(!this.equals((XObject)expr))
	return false;

	return true;
	}

	}

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