org.treetank.service.xml.xpath.operators

Class AbsObAxis

java.lang.Object

org.treetank.axis.AbsAxis

org.treetank.service.xml.xpath.operators.AbsObAxis

All Implemented Interfaces:

Iterable<Long>, Iterator<Long>

Direct Known Subclasses:

AddOpAxis, DivOpAxis, IDivOpAxis, ModOpAxis, MulOpAxis, SubOpAxis

public abstract class AbsObAxis
extends AbsAxis

AbstractOpAxis

Abstract axis for all operators performing an arithmetic operation.

Constructor Summary

Constructors

Constructor and Description
AbsObAxis(INodeReadTrx rtx, AbsAxis mOp1, AbsAxis mOp2) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract Type	getReturnType(int mOp1, int mOp2) Checks if the types of the operands are a valid combination for the operation and if so returns the corresponding result type.
boolean	hasNext()
protected abstract AtomicValue	operate(AtomicValue mOperand1, AtomicValue mOperand2) Performs the operation on the two input operands.
void	reset(long mNodeKey)

Methods inherited from class org.treetank.axis.AbsAxis

addAtomicToItemList, close, getItemList, getNode, getStartKey, isSelfIncluded, iterator, moveTo, next, remove, resetToLastKey, resetToStartKey

Methods inherited from class java.lang.Object

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

Constructor Detail

AbsObAxis

public AbsObAxis(INodeReadTrx rtx,
         AbsAxis mOp1,
         AbsAxis mOp2)

Constructor. Initializes the internal state.

Parameters:

rtx - Exclusive (immutable) trx to iterate with.

mOp1 - First value of the operation

mOp2 - Second value of the operation

Method Detail

reset

public final void reset(long mNodeKey)

Overrides:

reset in class AbsAxis

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<Long>

Specified by:

hasNext in class AbsAxis

operate

protected abstract AtomicValue operate(AtomicValue mOperand1,
                  AtomicValue mOperand2)
                                throws TTXPathException

Performs the operation on the two input operands. First checks if the types of the operands are a valid combination for the operation and if so computed the result. Otherwise an XPathError is thrown.

Parameters:

mOperand1 - first input operand

mOperand2 - second input operand

Returns:

result of the operation

Throws:

TTXPathException - if the operations fails

getReturnType

protected abstract Type getReturnType(int mOp1,
                 int mOp2)
                               throws TTXPathException

Checks if the types of the operands are a valid combination for the operation and if so returns the corresponding result type. Otherwise an XPathError is thrown. This typed check is done according to the Operator Mapping.

Parameters:

mOp1 - first operand's type key

mOp2 - second operand's type key

Returns:

return type of the arithmetic function according to the operand type combination.

Throws:

TTXPathException - if type is not specified