Kotlin implementation of the Semantic Versioning specification. Can be used from Java seamlessly.
The goal is to strictly comply with the SemVer parsing and precedence rules, and provide an easy-to-use API. Specifically it provides the ability to:
- Instantiate/parse semantic versions
- Compare/sort semantic versions
- Check if a semantic version fits within a set of constraints
The grammar can be seen here; it is consistent with the BNF grammar in the specification.
You can find the latest version on Bintray. 
I'll consider publishing to Maven Central and jcenter if people start using this library and find it useful.
A valid semantic version is represented by the SemVer class. The easiest way to instantiate it is by parsing a string:
SemVer.parseStr("1.0.0")
SemVer comprises NormalVersion, and optionally, PreReleaseVersion and BuildMetadata. The objects are immutable but there are
various builder methods that return new instances after appropriate modification.
More ways to instantiate a SemVer:
SemVer(NormalVersion(1, 0, 0))
SemVer(NormalVersion("1", "0", "0"))
SemVer(NormalVersion(1, 0, 0), PreReleaseVersion("alpha"), BuildMetadata(1))
v
.withMajorVersion(2).withMinorVersion(1).withPatchVersion(1)
.withPreReleaseVersion("alpha").withBuildMetadata(1)
v.withPreReleaseVersion() (empty) will remove the pre-release version. Same for v.withBuildMetadata().
See the KDoc for more details. This project has almost 100% test coverage, you're also welcome to look at the unit tests.
Other than BuildMetadata, the rest implement equals, hashCode, and Comparable.
From Kotlin code, you can use the usual comparison operators:
SemVer.parse("1.0.0") < SemVer.parse("1.0.1")
SemVer.parse("1.0.1") >= SemVer.parse("1.0.0")
From Java, use compareTo explicitly.
I don't see the point in providing a DSL for checking complicated constraints,
because all of those can be rewritten using compareTo. For example:
v.satisfies(">1.2.2") can be rewritten as v > SemVer.parse("1.2.2")
v.satisfies("1.2.+") can be rewritten as v >= SemVer.parse("1.2.0")
v.satisfies("(,1.8.9]") can be rewritten as v <= SemVer.parse("1.8.9")
v.satisfies("1.0-2.0") can be rewritten as v >= SemVer.parse("1.0.0") && v <= SemVer.parse("2.0.0")
See Semver cheatsheet for more examples.
This project is a volunteer effort. You are welcome to send pull requests, ask questions, or create issues. If you like it, you can help by spreading the word!
Copyright 2020 Abhijit Sarkar - Released under Apache License v2.0.