- /*
- * The Apache Software License, Version 1.1
- *
- *
- * Copyright (c) 1999 The Apache Software Foundation. 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. The end-user documentation included with the redistribution,
- * if any, must include the following acknowledgment:
- * "This product includes software developed by the
- * Apache Software Foundation (http://www.apache.org/)."
- * Alternately, this acknowledgment may appear in the software itself,
- * if and wherever such third-party acknowledgments normally appear.
- *
- * 4. The names "Xalan" and "Apache Software Foundation" must
- * not be used to endorse or promote products derived from this
- * software without prior written permission. For written
- * permission, please contact apache@apache.org.
- *
- * 5. Products derived from this software may not be called "Apache",
- * nor may "Apache" appear in their name, without prior written
- * permission of the Apache Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
- * ITS 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.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation and was
- * originally based on software copyright (c) 1999, Lotus
- * Development Corporation., http://www.lotus.com. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- */
- package org.apache.xpath.objects;
-
- import org.w3c.dom.DocumentFragment;
- //import org.w3c.dom.Text;
- //import org.w3c.dom.Node;
- import org.w3c.dom.NodeList;
- import org.w3c.dom.traversal.NodeIterator;
- import org.apache.xml.dtm.*;
-
- import java.io.Serializable;
-
- import org.apache.xpath.res.XPATHErrorResources;
- import org.apache.xpath.ExpressionOwner;
- import org.apache.xpath.XPathContext;
- import org.apache.xpath.NodeSetDTM;
- import org.apache.xpath.XPathException;
- import org.apache.xpath.XPathVisitor;
- import org.apache.xalan.res.XSLMessages;
- import org.apache.xpath.Expression;
- import org.apache.xml.utils.XMLString;
-
- /**
- * <meta name="usage" content="general"/>
- * 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.
- */
- public class XObject extends Expression implements Serializable, Cloneable
- {
-
- /**
- * 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)
- {
- 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();
-
- m_obj = 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 = new Double(num());
- break;
- case CLASS_NODESET :
- result = iter();
- break;
- case CLASS_BOOLEAN :
- result = new Boolean(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(java.util.Vector 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(org.apache.xml.utils.FastStringBuffer fsb)
- {
- fsb.append(str());
- }
-
- /**
- * @see 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;
- }
-
- }