Maven Versions Plugin

Version Range Specification

The RequireMavenVersion and RequireJavaVersion rules use the standard Maven version range syntax with one minor change for ease of use (denoted with *):

RangeMeaning
1.0x >= 1.0 * The default Maven meaning for 1.0 is everything (,) but with 1.0 recommended. Obviously this doesn't work for enforcing versions here, so it has been redefined as a minimum version.
(,1.0]x <= 1.0
(,1.0)x < 1.0
[1.0]x == 1.0
[1.0,)x >= 1.0
(1.0,)x > 1.0
(1.0,2.0)1.0 < x < 2.0
[1.0,2.0]1.0 <= x <= 2.0
(,1.0],[1.2,)x <= 1.0 or x >= 1.2. Multiple sets are comma-separated
(,1.1),(1.1,)x != 1.1

 

http://maven.apache.org/enforcer/enforcer-rules/versionRanges.html

 

http://books.sonatype.com/mvnref-book/reference/pom-relationships-sect-project-dependencies.html

Ref