org.deltava.comparators
Class AbstractComparator<T>

java.lang.Object
  org.deltava.comparators.AbstractComparator<T>

All Implemented Interfaces:

Serializable, Comparator<T>

Direct Known Subclasses:

AirportComparator, EquipmentComparator, FlightReportComparator, PerformanceComparator, PersonComparator, StaffComparator, TestComparator

public abstract class AbstractComparator<T>
extends Object
implements Comparator<T>, Serializable

Implements common comparator functions. NOTE: Most comparators in this package impose orderings that are inconsistent with equals.

Since:

1.0

Version:

3.0

Author:

Luke

See Also:

Serialized Form

Field Summary

protected int	_comparisonType The criteria by which to compare objects.
protected boolean	_reverseSort Are we doing a reverse sort?
protected String[]	_typeNames Text descriptions of the different comparison types.

Constructor Summary

protected

AbstractComparator(String[] typeNames) Create a new comparator with a given set of type names.

Method Summary

int	compare(T o1, T o2) Return the result by interrogating the implementation and applying a reverse sort if requred.
protected abstract int	compareImpl(T o1, T o2) This method does the actual comparison.
int	getComparisonType() Return the comparison type.
String[]	getTypeNames() Return the list of comparison type names.
boolean	isReverseSort() Return if we are performing a reverse sort.
void	setComparisonType(int type) Sets the comparison type.
void	setComparisonType(String type) Sets the comparison type.
void	setReverseSort(boolean rSort) Updates the reverse sort parameter to sort in descending order.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals

Field Detail

_reverseSort

protected boolean _reverseSort

Are we doing a reverse sort?

_comparisonType

protected int _comparisonType

The criteria by which to compare objects.

_typeNames

protected String[] _typeNames

Text descriptions of the different comparison types.

Constructor Detail

AbstractComparator

protected AbstractComparator(String[] typeNames)

Create a new comparator with a given set of type names.

Parameters:

typeNames - An array of type names

Throws:

NullPointerException - if typeNames is null

Method Detail

compareImpl

protected abstract int compareImpl(T o1,
                                   T o2)

This method does the actual comparison. It is called and then we modify the result if we are performing a reverse sort.

Parameters:

o1 - The first object to compare

o2 - The second object to compare

Returns:

-1, 0, 1 as defined by the compareTo(Object, Object) interface

Throws:

ClassCastException - if the object types are not supported by this implementation

See Also:

compare(Object, Object), Comparator.compare(java.lang.Object, java.lang.Object)

setComparisonType

public void setComparisonType(int type)

Sets the comparison type.

Parameters:

type - The comparison type.

Throws:

IllegalArgumentException - if the type is negative or > typeNames.length

See Also:

getComparisonType()

setComparisonType

public void setComparisonType(String type)

Sets the comparison type.

Parameters:

type - The comparison type, contained within _typeNames

Throws:

IllegalArgumentException - if the type is not found in _typeNames

See Also:

getTypeNames()

getTypeNames

public String[] getTypeNames()

Return the list of comparison type names.

Returns:

an array of type names

isReverseSort

public boolean isReverseSort()

Return if we are performing a reverse sort.

Returns:

TRUE if a reverse sort

See Also:

setReverseSort(boolean)

getComparisonType

public int getComparisonType()

Return the comparison type.

Returns:

The comparison type in use

See Also:

setComparisonType(int), setComparisonType(String)

setReverseSort

public final void setReverseSort(boolean rSort)

Updates the reverse sort parameter to sort in descending order.

Parameters:

rSort - TRUE if sorting in descending order, otherwise FALSE

See Also:

isReverseSort()

compare

public final int compare(T o1,
                         T o2)

Return the result by interrogating the implementation and applying a reverse sort if requred.

Specified by:

compare in interface Comparator<T>

Parameters:

o1 - The first object to compare

o2 - The second object to compare

Returns:

-1, 0, 1 as defined by the compareTo(Object, Object) interface

Throws:

ClassCastException - if the object types are not supported by this implementation

See Also:

compareImpl(Object, Object), Comparator.compare(java.lang.Object, java.lang.Object)