org.apache.xalan.templates
Class XUnresolvedVariable

java.lang.Object
  org.apache.xpath.Expression
      org.apache.xpath.objects.XObject
          org.apache.xalan.templates.XUnresolvedVariable

All Implemented Interfaces:

Cloneable, ExpressionNode, Serializable, javax.xml.transform.SourceLocator, XPathVisitable

public class XUnresolvedVariable

extends XObject

An instance of this class holds unto a variable until it is executed. It is used at this time for global variables which must (we think) forward reference.

See Also:

Serialized Form

Field Summary

private int	m_context The node context for execution.
private boolean	m_doneEval true if this variable or parameter is not currently being evaluated.
private boolean	m_isGlobal true if this variable or parameter is a global.
private TransformerImpl	m_transformer The transformer context for execution.
private int	m_varStackContext An index into the variable stack where the variable context ends, i.e. at the point we should terminate the search.
private int	m_varStackPos An index to the point in the variable stack where we should begin variable searches for evaluation of expressions.

Fields inherited from class org.apache.xpath.objects.XObject

CLASS_BOOLEAN, CLASS_NODESET, CLASS_NULL, CLASS_NUMBER, CLASS_RTREEFRAG, CLASS_STRING, CLASS_UNKNOWN, CLASS_UNRESOLVEDVARIABLE, m_obj

Fields inherited from class org.apache.xpath.Expression

Constructor Summary

XUnresolvedVariable(ElemVariable obj, int sourceNode, TransformerImpl transformer, int varStackPos, int varStackContext, boolean isGlobal)
Create an XUnresolvedVariable, that may be executed at a later time.

Method Summary

XObject	execute(XPathContext xctxt) For support of literal objects in xpaths.
int	getType() Tell what kind of class this is.
String	getTypeString() Given a request type, return the equivalent string.
void	setVarStackContext(int bottom) Set an index into the variable stack where the variable context ends, i.e. at the point we should terminate the search.
void	setVarStackPos(int top) Set an index to the point in the variable stack where we should begin variable searches for evaluation of expressions.

Methods inherited from class org.apache.xpath.objects.XObject

allowDetachToRelease, appendToFsb, bool, boolWithSideEffects, callVisitors, castToType, create, create, deepEquals, destruct, detach, dispatchCharactersEvents, equals, error, error, fixupVariables, getFresh, greaterThan, greaterThanOrEqual, iter, lessThan, lessThanOrEqual, mutableNodeset, nodelist, nodeset, notEquals, num, numWithSideEffects, object, reset, rtf, rtf, rtree, rtree, str, toString, xstr

Methods inherited from class org.apache.xpath.Expression

asIterator, asIteratorRaw, asNode, assertion, bool, canTraverseOutsideSubtree, error, execute, execute, execute, executeCharsToContentHandler, exprAddChild, exprGetChild, exprGetNumChildren, exprGetParent, exprSetParent, getColumnNumber, getExpressionOwner, getLineNumber, getPublicId, getSystemId, isNodesetExpr, isSameClass, isStableNumber, num, warn, xstr

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

m_context

private transient int m_context

The node context for execution.

m_transformer

private transient TransformerImpl m_transformer

The transformer context for execution.

m_varStackPos

private transient int m_varStackPos

An index to the point in the variable stack where we should begin variable searches for evaluation of expressions. This is -1 if m_isTopLevel is false.

m_varStackContext

private transient int m_varStackContext

An index into the variable stack where the variable context ends, i.e. at the point we should terminate the search.

m_isGlobal

private boolean m_isGlobal

true if this variable or parameter is a global.

m_doneEval

private transient boolean m_doneEval

true if this variable or parameter is not currently being evaluated.

Constructor Detail

XUnresolvedVariable

public XUnresolvedVariable(ElemVariable obj,
                           int sourceNode,
                           TransformerImpl transformer,
                           int varStackPos,
                           int varStackContext,
                           boolean isGlobal)

Create an XUnresolvedVariable, that may be executed at a later time. This is primarily used so that forward referencing works with global variables. An XUnresolvedVariable is initially pushed into the global variable stack, and then replaced with the real thing when it is accessed.

Parameters:

obj - Must be a non-null reference to an ElemVariable.

sourceNode - The node context for execution.

transformer - The transformer execution context.

varStackPos - An index to the point in the variable stack where we should begin variable searches for evaluation of expressions.

varStackContext - An index into the variable stack where the variable context ends, i.e. at the point we should terminate the search.

isGlobal - true if this is a global variable.

Method Detail

execute

public XObject execute(XPathContext xctxt)
                throws javax.xml.transform.TransformerException

For support of literal objects in xpaths.

Overrides:

execute in class XObject

Parameters:

xctxt - The XPath execution context.

Returns:

This object.

Throws:

javax.xml.transform.TransformerException

setVarStackPos

public void setVarStackPos(int top)

Set an index to the point in the variable stack where we should begin variable searches for evaluation of expressions. This is -1 if m_isTopLevel is false.

Parameters:

top - A valid value that specifies where in the variable stack the search should begin.

setVarStackContext

public void setVarStackContext(int bottom)

Set an index into the variable stack where the variable context ends, i.e. at the point we should terminate the search.

getType

public int getType()

Tell what kind of class this is.

Overrides:

getType in class XObject

Returns:

CLASS_UNRESOLVEDVARIABLE

getTypeString

public String getTypeString()

Given a request type, return the equivalent string. For diagnostic purposes.

Overrides:

getTypeString in class XObject

Returns:

An informational string.