Package org.apache.tinkerpop.gremlin.util

Class GremlinValueComparator

java.lang.Object

org.apache.tinkerpop.gremlin.util.GremlinValueComparator

All Implemented Interfaces:

Comparator<Object>

public abstract class GremlinValueComparator
extends Object
implements Comparator<Object>

An implementation of the Comparability/Orderability semantics as defined in the Apache TinkerPop Provider documentation.

Author:

Mike Personick (http://github.com/mikepersonick)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	GremlinValueComparator.Type	The typespace.

Field Summary

Fields

Modifier and Type	Field	Description
static GremlinValueComparator	COMPARABILITY	Comparability has very similar semantics to orderability with the following exceptions: 1.
static GremlinValueComparator	ORDERABILITY	Orderability comparator allows for a total order across all types (no type error exceptions).

Method Summary

Modifier and Type	Method	Description
static boolean	comparable(Object f, Object s)	Return true if the two objects are of the same comparison type (although they may not be the exact same Class)
protected Comparator	comparator(GremlinValueComparator.Type type)
abstract int	compare(Object f, Object s)	Compare(a,b) is defined differently for Comparablity vs.
abstract boolean	equals(Object f, Object s)	Equals(a,b) is defined differently for Comparablity (equality) vs.

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, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Field Detail

ORDERABILITY

public static final GremlinValueComparator ORDERABILITY

Orderability comparator allows for a total order across all types (no type error exceptions).

COMPARABILITY

public static final GremlinValueComparator COMPARABILITY

Comparability has very similar semantics to orderability with the following exceptions: 1. NaN is not equal to anything, including itself, and cannot be compared to anything: equals(NaN, anything) = FALSE compare(NaN, anything) = ERROR 2. Unlike Orderability, Comparability is limited to a single type space: compare(type1, type2) = ERROR Note that because of type errors for Comparability, equals(a,b) does not necessarily produce the same result as compare(a,b) == 0. Make sure to use equals(a,b) for P.eq/neq.

Method Detail

comparable

public static boolean comparable(Object f,
                                 Object s)

Return true if the two objects are of the same comparison type (although they may not be the exact same Class)

comparator

protected Comparator comparator(GremlinValueComparator.Type type)

compare

public abstract int compare(Object f,
                            Object s)

Compare(a,b) is defined differently for Comparablity vs. Orderability.

Specified by:

compare in interface Comparator<Object>

equals

public abstract boolean equals(Object f,
                               Object s)

Equals(a,b) is defined differently for Comparablity (equality) vs. Orderability (equivalence).