org.apache.xpath.operations
Class UnaryOperation

java.lang.Object
  |
  +--org.apache.xpath.Expression
        |
        +--org.apache.xpath.operations.UnaryOperation

Direct Known Subclasses:

Bool, Neg, Number, String

public abstract class UnaryOperation

extends Expression

The unary operation base class.

See Also:

Serialized Form

Constructor Summary

UnaryOperation()

Method Summary

boolean	canTraverseOutsideSubtree() Tell if this expression or it's subexpressions can traverse outside the current subtree.
XObject	execute(XPathContext xctxt) Execute the operand and apply the unary operation to the result.
abstract XObject	operate(XObject right) Apply the operation to two operands, and return the result.
void	setRight(Expression r) Set the expression operand for the operation.

Methods inherited from class org.apache.xpath.Expression

assert, error, setSourceLocator, warn

Methods inherited from class java.lang.Object

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

Constructor Detail

UnaryOperation

public UnaryOperation()

Method Detail

canTraverseOutsideSubtree

public boolean canTraverseOutsideSubtree()

Tell if this expression or it's subexpressions can traverse outside the current subtree.

Returns:

true if traversal outside the context node's subtree can occur.

Overrides:

canTraverseOutsideSubtree in class Expression

setRight

public void setRight(Expression r)

Set the expression operand for the operation.

Parameters:

r - The expression operand to which the unary operation will be applied.

execute

public XObject execute(XPathContext xctxt)
                throws TransformerException

Execute the operand and apply the unary operation to the result.

Parameters:

xctxt - The runtime execution context.

Returns:

An XObject that represents the result of applying the unary operation to the evaluated operand.

Throws:

TransformerException -

Overrides:

execute in class Expression

operate

public abstract XObject operate(XObject right)
                         throws TransformerException

Apply the operation to two operands, and return the result.

Parameters:

right - non-null reference to the evaluated right operand.

Returns:

non-null reference to the XObject that represents the result of the operation.

Throws:

TransformerException -