## org.apache.xpath.objects
Class XNumber

    java.lang.Object
      org.apache.xpath.Expression
          org.apache.xpath.objects.XObject
              org.apache.xpath.objects.XNumber

All Implemented Interfaces:
  java.io.Serializable, java.lang.Cloneable, javax.xml.transform.SourceLocator, ExpressionNode, XPathVisitable

    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
Usage:

Field Summary

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)` This will traverse the heararchy, calling the visitor for each member.
`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:
    `num` - Value of the object

Method Detail

### getType

    public int getType()

  Tell that this is a CLASS_NUMBER.

  Overrides:
    `getType` in class `XObject`
  Returns:
    node type CLASS_NUMBER

### getTypeString

    public java.lang.String getTypeString()

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

  Overrides:
    `getTypeString` in class `XObject`
  Returns:
    type string "#NUMBER"

### num

    public double num()

  Cast result object to a number.

  Overrides:
    `num` in class `XObject`
  Returns:
    the value of the XNumber object

### num

    public double num(XPathContext xctxt)
               throws javax.xml.transform.TransformerException

  Evaluate expression to a number.

  Overrides:
    `num` in class `Expression`
  Parameters:
    `xctxt` - The XPath runtime context.
  Returns:
    0.0
  Throws:
    `javax.xml.transform.TransformerException`

### bool

    public boolean bool()

  Cast result object to a boolean.

  Overrides:
    `bool` in class `XObject`
  Returns:
    false if the value is NaN or equal to 0.0

### str

    public java.lang.String str()

  Cast result object to a string.

  Overrides:
    `str` in class `XObject`
  Returns:
    "NaN" if the number is NaN, Infinity or -Infinity if the number is infinite or the string value of the number.

### object

    public java.lang.Object object()

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

  Overrides:
    `object` in class `XObject`
  Returns:
    The value of this XNumber as a Double object

### equals

    public boolean equals(XObject obj2)

  Tell if two objects are functionally equal.

  Overrides:
    `equals` in class `XObject`
  Parameters:
    `obj2` - Object to compare this to
  Returns:
    true if the two objects are equal
  Throws:
    `javax.xml.transform.TransformerException`

### 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.

  Overrides:
    `isStableNumber` in class `Expression`
  Returns:
    true if the expression represents a stable number.

### callVisitors

    public void callVisitors(ExpressionOwner owner,
                             XPathVisitor visitor)

  Description copied from interface: `XPathVisitable`
  This will traverse the heararchy, calling the visitor for each member. If the called visitor method returns false, the subtree should not be called.

  Specified by:
    `callVisitors` in interface `XPathVisitable`
  Overrides:
    `callVisitors` in class `XObject`
  Parameters:
    `owner` - The owner of the visitor, where that path may be rewritten if needed.
    `visitor` - The visitor whose appropriate method will be called.
  See Also:
    `XPathVisitable.callVisitors(ExpressionOwner, XPathVisitor)`

Copyright © 2005 Apache XML Project. All Rights Reserved.