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 and Description
static class	GremlinValueComparator.Type The typespace.

Field Summary

Fields

Modifier and Type	Field and 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 and Description
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

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, 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

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).