org.apache.brooklyn.util.text

Class VersionComparator

java.lang.Object

org.apache.brooklyn.util.text.VersionComparator

All Implemented Interfaces:

java.util.Comparator<java.lang.String>

public class VersionComparator
extends java.lang.Object
implements java.util.Comparator<java.lang.String>

Comparator for version strings.

This gives the desired semantics for our recommended version syntax, following major.minor.patch-qualifier syntax, doing numeric order of major/minor/patch (1.10 > 1.9), treating anything with a qualifier lower than the corresponding without but higher than items before (1.2 > 1.2-rc > 1.1), SNAPSHOT items always lowest rated (1.0 > 2-SNAPSHOT), and qualifier sorting follows NaturalOrderComparator (1-M10 > 1-M9).

Impossible to follow semantics for all versioning schemes but does the obvious right thing for normal schemes and pretty well in fringe cases. Probably the most surprising fringe behaviours will be 1.2.3.4 < 1.2.3 (the ".4" is considered a qualifier).

See test case for lots of examples.

Field Summary

Fields

Modifier and Type	Field and Description
static VersionComparator	INSTANCE

Constructor Summary

Constructors

Constructor and Description
VersionComparator()

Method Summary

Modifier and Type	Method and Description
int	compare(java.lang.String v1, java.lang.String v2)
static VersionComparator	getInstance()
static boolean	isSnapshot(java.lang.String version)

Methods inherited from class java.lang.Object

equals, 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

INSTANCE

public static final VersionComparator INSTANCE

Constructor Detail

VersionComparator

public VersionComparator()

Method Detail

getInstance

public static VersionComparator getInstance()

isSnapshot

public static boolean isSnapshot(java.lang.String version)

compare

public int compare(java.lang.String v1,
                   java.lang.String v2)

Specified by:

compare in interface java.util.Comparator<java.lang.String>