Oracle Coherence for C++ API: EntryComparator Class Reference

Detailed Description

Comparator implementation used to compare map entries.

Depending on the comparison style this comparator will compare entries' values, entries' keys or, when the provided comparator is an instance of QueryMapComparator, the entries themselves.

Author:

nsa 2008.05.30

Public Types

typedef spec::Handle

Handle

EntryComparator Handle definition.

typedef spec::View

View

EntryComparator View definition.

typedef spec::Holder

Holder

EntryComparator Holder definition.

Public Member Functions

virtual int32_t

compare (Object::View vO1, Object::View vO2) const

Compares two arguments for order.

virtual void

readExternal (PofReader::Handle hIn)

virtual void

writeExternal (PofWriter::Handle hOut) const

virtual bool

equals (Object::View v) const

int32_t

getComparisonStyle ()

Obtain the comparison style value utilized by this EntryComparator.

bool

isCompareValue ()

Check whether or not this EntryComparator uses entries' values to pass for comparison to the underlying Comparator.

bool

isCompareKey ()

Check whether or not this EntryComparator uses entries' keys to pass for comparison to the underlying Comparator.

bool

isCompareEntry ()

Check whether or not this EntryComparator pass entries themselves for comparison to the underlying QueryMapComparator::compareEntries method.

Static Public Attributes

static const int32_t

cmp_auto

Indicates that this EntryComparator should choose the comparison style based on the underying comparator type.

static const int32_t

cmp_value

Indicates that this EntryComparator should compare the entries' values.

static const int32_t

cmp_key

Indicates that this EntryComparator should compare the entries' keys.

static const int32_t

cmp_entry

Indicates that entries that implement com.tangosol.util.QueryMap.Entry interface will be compared using the QueryMapComparator::compareEntries method.

Protected Member Functions

EntryComparator ()

Default constructor (necessary for the PortableObject interface).

EntryComparator (Comparator::View vComparator, int32_t nStyle=cmp_auto)

Construct a SafeComparator delegating to the specified (wrapped) comparator.

Protected Attributes

int32_t

m_nStyle

Comparison style utilized by this EntryComparator.

Constructor & Destructor Documentation

EntryComparator	(	Comparator::View	vComparator,
		int32_t	nStyle = `cmp_auto`
	)			`[protected]`

Construct a SafeComparator delegating to the specified (wrapped) comparator.

Parameters:

vComparator

Comparator object to delegate comparison of non-null values (optional)

Member Function Documentation

virtual int32_t compare	(	Object::View	vO1,
		Object::View	vO2
	)			const `[virtual]`

Compares two arguments for order.

The arguments must be coherence::util::Map::Entry objects. Depending on the comparison style, this method will pass either the entries' values, keys or the entries themselves to the underlying Comparator.

Parameters:

	vO1	the first object to be compared
	vO2	the second object to be compared

Returns:: a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second

Exceptions:

ClassCastException

if the arguments' types prevent them from being compared by this Comparator.

Reimplemented from SafeComparator.

int32_t getComparisonStyle ( )

Obtain the comparison style value utilized by this EntryComparator.

The returned value should be one of the CMP_* constants.

Returns:: the comparison style value

bool isCompareValue ( )

Check whether or not this EntryComparator uses entries' values to pass for comparison to the underlying Comparator.

Returns:: true iff entries' values are used for comparison

bool isCompareKey ( )

Check whether or not this EntryComparator uses entries' keys to pass for comparison to the underlying Comparator.

Returns:: true iff entries' keys are used for comparison

bool isCompareEntry ( )

Check whether or not this EntryComparator pass entries themselves for comparison to the underlying QueryMapComparator::compareEntries method.

Returns:: true iff entries themselves are used for comparison

Member Data Documentation

int32_t m_nStyle [protected]

Comparison style utilized by this EntryComparator.

Valid values are any of the CMP_* constants.