org.treetank.service.xml.xpath.comparators

Class ValueComp

java.lang.Object

org.treetank.axis.AbsAxis

org.treetank.service.xml.xpath.comparators.AbsComparator

org.treetank.service.xml.xpath.comparators.ValueComp

All Implemented Interfaces:

Iterable<Long>, Iterator<Long>

public class ValueComp
extends AbsComparator

ValueComp

Value comparisons are used for comparing single values.

Constructor Summary

Constructors

Constructor and Description
ValueComp(INodeReadTrx rtx, AbsAxis mOperand1, AbsAxis mOperand2, CompKind mComp) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected AtomicValue[]	atomize(AbsAxis mOperand) Atomizes an operand according to the rules specified in the XPath specification.
protected boolean	compare(AtomicValue[] mOperand1, AtomicValue[] mOperand2) Performs the comparison of two atomic values.
protected Type	getType(int mKey1, int mKey2) Returns the common comparable type of the two operands, or an error, if the two operands don't have a common type on which a comparison is allowed according to the XPath 2.0 specification.

Methods inherited from class org.treetank.service.xml.xpath.comparators.AbsComparator

getComparator, getCompKind, hasNext, hook, reset

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

ValueComp

public ValueComp(INodeReadTrx rtx,
         AbsAxis mOperand1,
         AbsAxis mOperand2,
         CompKind mComp)

Constructor. Initializes the internal state.

Parameters:

rtx - Exclusive (immutable) trx to iterate with.

mOperand1 - First value of the comparison

mOperand2 - Second value of the comparison

mComp - comparison kind

Method Detail

compare

protected boolean compare(AtomicValue[] mOperand1,
              AtomicValue[] mOperand2)
                   throws TTXPathException

Performs the comparison of two atomic values.

Specified by:

compare in class AbsComparator

Parameters:

mOperand1 - first comparison operand.

mOperand2 - second comparison operand.

Returns:

the result of the comparison

Throws:

TTXPathException

atomize

protected AtomicValue[] atomize(AbsAxis mOperand)
                         throws TTXPathException

Atomizes an operand according to the rules specified in the XPath specification.

Specified by:

atomize in class AbsComparator

Parameters:

mOperand - the operand that will be atomized.

Returns:

the atomized operand. (always an atomic value)

Throws:

TTXPathException - if any goes wrong.

getType

protected Type getType(int mKey1,
           int mKey2)
                throws TTXPathException

Returns the common comparable type of the two operands, or an error, if the two operands don't have a common type on which a comparison is allowed according to the XPath 2.0 specification.

Specified by:

getType in class AbsComparator

Parameters:

mKey1 - first comparison operand's type key

mKey2 - second comparison operand's type key

Returns:

the type the comparison can be evaluated on

Throws:

TTXPathException