com.pervasive.datarush.tokens

Class TokenComparators

java.lang.Object

com.pervasive.datarush.tokens.TokenComparators

public class TokenComparators
extends Object

A factory for creating TokenComparator objects.

Method Summary

Methods

Modifier and Type	Method and Description
static TokenComparator	getComparator(TokenType type) Creates a comparator appropriate for the given type.
static TokenComparator	getComparator(TokenType type, TokenOrder order) Creates a comparator appropriate for the given type ordered in the specified direction.
static TokenComparator	getComparator(TokenValued left, TokenValued right) Creates a comparator, bound to the given left and right values.
static RecordTokenComparator	getCompositeComparator(ScalarTokenType[] types, TokenOrder order) Creates a composite comparator appropriate for the given types ordered in the specified direction.
static RecordTokenComparator	getCompositeComparator(ScalarTokenType[] types, TokenOrder[] order) Creates a composite comparator appropriate for the given types ordered in the specified direction for each field.
static RecordTokenComparator	getCompositeComparator(ScalarValued[] left, ScalarValued[] right, TokenOrder order) Creates a composite comparator, bound to the given sets of left and right values, using the specified ordering for all pairings of values.
static RecordTokenComparator	getCompositeComparator(ScalarValued[] left, ScalarValued[] right, TokenOrder[] order) Creates a composite comparator, bound to the given sets of left and right values, using the specified orderings for each pairing of values.

Methods inherited from class java.lang.Object

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

Method Detail

getComparator

public static TokenComparator getComparator(TokenType type)

Creates a comparator appropriate for the given type. If the the given type is a record type, all fields are evaluated in the comparison.

Parameters:

type - the token type for which to create a comparator

Returns:

a new comparator object

getComparator

public static TokenComparator getComparator(TokenValued left,
                            TokenValued right)

Creates a comparator, bound to the given left and right values. The two values must be of comparable types; the resulting comparator will be of the narrowest possible type for the comparison. If the given values are of record type, all fields are evaluated in the comparison.

Parameters:

left - the value to bind to the left operand in comparisons

right - the value to bind to the right operand in comparisons

Returns:

a new comparator bound to the given values

getComparator

public static TokenComparator getComparator(TokenType type,
                            TokenOrder order)

Creates a comparator appropriate for the given type ordered in the specified direction. If the the given type is a record type, all fields are evaluated in the comparison.

Parameters:

type - the token type for which to create a comparator

order - the direction of the ordering

Returns:

a new comparator object

getCompositeComparator

public static RecordTokenComparator getCompositeComparator(ScalarTokenType[] types,
                                           TokenOrder order)

Creates a composite comparator appropriate for the given types ordered in the specified direction.

Parameters:

types - the token types of individual fields. The comparator will expect values in the same order as the argument.

order - the direction of the ordering. All fields will be compared under this ordering.

Returns:

a new comparator object

getCompositeComparator

public static RecordTokenComparator getCompositeComparator(ScalarValued[] left,
                                           ScalarValued[] right,
                                           TokenOrder order)

Creates a composite comparator, bound to the given sets of left and right values, using the specified ordering for all pairings of values. The two values in each pair must be of comparable types; the resulting comparator will be of the narrowest possible type for the comparison.

Parameters:

left - the set of values to bind to the fields of the left operand in comparisons

right - the set of values to bind to the fields of the right operand in comparisons

order - the ordering for all fields

Returns:

a new comparator bound to the given values

getCompositeComparator

public static RecordTokenComparator getCompositeComparator(ScalarTokenType[] types,
                                           TokenOrder[] order)

Creates a composite comparator appropriate for the given types ordered in the specified direction for each field.

Parameters:

types - the token types of individual fields. The comparator will expect values in the same order as the argument.

order - the direction of the orderings for each field.

Returns:

a new comparator object

getCompositeComparator

public static RecordTokenComparator getCompositeComparator(ScalarValued[] left,
                                           ScalarValued[] right,
                                           TokenOrder[] order)

Creates a composite comparator, bound to the given sets of left and right values, using the specified orderings for each pairing of values. The two values in each pair must be of comparable types; the resulting comparator will be of the narrowest possible type for the comparison.

Parameters:

left - the set of values to bind to the fields of the left operand in comparisons

right - the set of values to bind to the fields of the right operand in comparisons

order - the set of orderings for each field

Returns:

a new comparator bound to the given values