org.apache.xpath.objects
Class XNumber

java.lang.Object
  |
  +--org.apache.xpath.Expression
        |
        +--org.apache.xpath.objects.XObject
              |
              +--org.apache.xpath.objects.XNumber

public class XNumber

extends XObject

This class represents an XPath number, and is capable of converting the number to other types, such as a string.

See Also:

Serialized Form

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

Constructor Summary

XNumber(double d)
Construct a XNodeSet object.

XNumber(java.lang.Number num)
Construct a XNodeSet object.

Method Summary

boolean	bool() Cast result object to a boolean.
void	callVisitors(ExpressionOwner owner, XPathVisitor visitor)
boolean	equals(XObject obj2) Tell if two objects are functionally equal.
int	getType() Tell that this is a CLASS_NUMBER.
java.lang.String	getTypeString() Given a request type, return the equivalent string.
boolean	isStableNumber() Tell if this expression returns a stable number that will not change during iterations within the expression.
double	num() Cast result object to a number.
double	num(XPathContext xctxt) Evaluate expression to a number.
java.lang.Object	object() Return a java object that's closest to the representation that should be handed to an extension.
java.lang.String	str() Cast result object to a string.

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

allowDetachToRelease, appendToFsb, boolWithSideEffects, castToType, create, create, deepEquals, destruct, detach, dispatchCharactersEvents, execute, fixupVariables, getFresh, greaterThan, greaterThanOrEqual, iter, lessThan, lessThanOrEqual, mutableNodeset, nodelist, nodeset, notEquals, numWithSideEffects, reset, rtf, rtf, rtree, rtree, 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, warn, xstr

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

XNumber

public XNumber(double d)

Construct a XNodeSet object.

Parameters:

d - Value of the object

XNumber

public XNumber(java.lang.Number num)

Construct a XNodeSet object.

Parameters:

d - Value of the object

Method Detail

getType

public int getType()

Tell that this is a CLASS_NUMBER.

Returns:

node type CLASS_NUMBER

Overrides:

getType in class XObject

getTypeString

public java.lang.String getTypeString()

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

Returns:

type string "#NUMBER"

Overrides:

getTypeString in class XObject

num

public double num()

Cast result object to a number.

Returns:

the value of the XNumber object

Overrides:

num in class XObject

num

public double num(XPathContext xctxt)
           throws TransformerException

Evaluate expression to a number.

Returns:

0.0

Throws:

TransformerException -

Overrides:

num in class Expression

bool

public boolean bool()

Cast result object to a boolean.

Returns:

false if the value is NaN or equal to 0.0

Overrides:

bool in class XObject

str

public java.lang.String str()

Cast result object to a string.

Returns:

"NaN" if the number is NaN, Infinity or -Infinity if the number is infinite or the string value of the number.

Overrides:

str in class XObject

object

public java.lang.Object object()

Return a java object that's closest to the representation that should be handed to an extension.

Returns:

The value of this XNumber as a Double object

Overrides:

object in class XObject

equals

public boolean equals(XObject obj2)

Tell if two objects are functionally equal.

Parameters:

obj2 - Object to compare this to

Returns:

true if the two objects are equal

Throws:

TransformerException -

Overrides:

equals in class XObject

isStableNumber

public boolean isStableNumber()

Tell if this expression returns a stable number that will not change during iterations within the expression. This is used to determine if a proximity position predicate can indicate that no more searching has to occur.

Returns:

true if the expression represents a stable number.

Overrides:

isStableNumber in class Expression

callVisitors

public void callVisitors(ExpressionOwner owner,
                         XPathVisitor visitor)

Overrides:

callVisitors in class XObject

See Also:

XPathVisitable#callVisitors(ExpressionOwner, XPathVisitor)