Java SemVer v0.6.0

Java SemVer is a Java implementation of the Semantic Versioning Specification (http://semver.org/).

NOTE: The current version of the Java SemVer corresponds to the Semantic Versioning 2.0.0-rc.2.

Versioning

Java SemVer is versioned according to the SemVer Specification.

NOTE: The current release of the Java SemVer library has a major version of zero which according to the SemVer p.4 means that the library is under initial development and its public API should not be considered stable.

Usage

Below are some common use cases for the Java SemVer library.

Creating Versions

Java SemVer library is composed of one small package which contains a few classes. All the classes but one are package-private and are not accessible outside the package. The only public class is Version which acts as a facade for the client code. By design, the Version class is made immutable by making its constructor package-private, so that it can not be subclassed or directly instantiated. Instead of public constructor, the Version class provides a static factory method, Version.valueOf(String value).

import com.github.zafarkhaja.semver.Version;

Version v = Version.valueOf("1.0.0-rc.1+build.1");

int major = v.getMajorVersion(); // 1
int minor = v.getMinorVersion(); // 0
int patch = v.getPatchVersion(); // 0

String normal     = v.getNormalVersion();     // "1.0.0"
String preRelease = v.getPreReleaseVersion(); // "rc.1"
String build      = v.getBuildMetadata();     // "build.1"

String str = v.toString(); // "1.0.0-rc.1+build.1"

Another way to create a Version is to use a builder class Version.Builder.

import com.github.zafarkhaja.semver.Version;

Version.Builder builder = new Version.Builder("1.0.0");
builder.setPreReleaseVersion("rc.1");
builder.setBuildMetadata("build.1");

Version v = builder.build();

int major = v.getMajorVersion(); // 1
int minor = v.getMinorVersion(); // 0
int patch = v.getPatchVersion(); // 0

String normal     = v.getNormalVersion();     // "1.0.0"
String preRelease = v.getPreReleaseVersion(); // "rc.1"
String build      = v.getBuildMetadata();     // "build.1"

String str = v.toString(); // "1.0.0-rc.1+build.1"

Incrementing Versions

Because the Version class is immutable, the incrementors return a new instance of Version rather than modifying the given one. Each of the normal version incrementors has an overloaded method that takes a pre-release version as an argument.

import com.github.zafarkhaja.semver.Version;

Version v1 = Version.valueOf("1.2.3");

// Incrementing major version
Version v2 = v1.incrementMajorVersion();        // "2.0.0"
Version v2 = v1.incrementMajorVersion("alpha"); // "2.0.0-alpha"

// Incrementing minor version
Version v3 = v1.incrementMinorVersion();        // "1.3.0"
Version v3 = v1.incrementMinorVersion("alpha"); // "1.3.0-alpha"

// Incrementing patch version
Version v4 = v1.incrementPatchVersion();        // "1.2.4"
Version v4 = v1.incrementPatchVersion("alpha"); // "1.2.4-alpha"

// Original Version is still the same
String str = v1.toString(); // "1.2.3"

There are also incrementor methods for pre-release version and build metadata.

import com.github.zafarkhaja.semver.Version;

// Incrementing pre-release version
Version v1 = Version.valueOf("1.2.3-rc");        // considered as "rc.0"
Version v2 = v1.incrementPreReleaseVersion();    // "1.2.3-rc.1"
Version v3 = v2.incrementPreReleaseVersion();    // "1.2.3-rc.2"

// Incrementing build metadata
Version v1 = Version.valueOf("1.2.3-rc+build");  // considered as "build.0"
Version v2 = v1.incrementBuildMetadata();        // "1.2.3-rc+build.1"
Version v3 = v2.incrementBuildMetadata();        // "1.2.3-rc+build.2"

When incrementing normal or pre-release versions build metadata is always dropped.

import com.github.zafarkhaja.semver.Version;

Version v1 = Version.valueOf("1.2.3-beta+build");

// Incrementing normal version
Version v2 = v1.incrementMajorVersion();        // "2.0.0"
Version v2 = v1.incrementMajorVersion("alpha"); // "2.0.0-alpha"

Version v3 = v1.incrementMinorVersion();        // "1.3.0"
Version v3 = v1.incrementMinorVersion("alpha"); // "1.3.0-alpha"

Version v4 = v1.incrementPatchVersion();        // "1.2.4"
Version v4 = v1.incrementPatchVersion("alpha"); // "1.2.4-alpha"

// Incrementing pre-release version
Version v2 = v1.incrementPreReleaseVersion();   // "1.2.3-beta.1"

NOTE: The discussion page https://github.com/mojombo/semver/issues/60 might be of good use in better understanding some of the decisions made regarding the incrementor methods.

Comparing Versions

Comparing versions with Java SemVer is easy. The Version class implements the Comparable interface, it also overrides the Object.equals(Object obj) method and provides some more methods for convenient comparing.

import com.github.zafarkhaja.semver.Version;

Version v1 = Version.valueOf("1.0.0-rc.1+build.1");
Version v2 = Version.valueOf("1.3.7+build.2.b8f12d7");

int result = v1.compareTo(v2);  // < 0
boolean result = v1.equals(v2); // false

boolean result = v1.greaterThan(v2);           // false
boolean result = v1.greaterThanOrEqualsTo(v2); // false
boolean result = v1.lessThan(v2);              // true
boolean result = v1.lessThanOrEqualsTo(v2);    // true

When determining version precedence build metadata is ignored (SemVer p.10).

import com.github.zafarkhaja.semver.Version;

Version v1 = Version.valueOf("1.0.0+build.1");
Version v2 = Version.valueOf("1.0.0+build.2");

int result = v1.compareTo(v2);  // = 0
boolean result = v1.equals(v2); // true

Sometimes, however, you might want to compare versions with build metadata in mind. For such cases Java SemVer provides a comparator Version.BUILD_AWARE_ORDER and a convenience method Version.compareWithBuildsTo(Version other).

import com.github.zafarkhaja.semver.Version;

Version v1 = Version.valueOf("1.0.0+build.1");
Version v2 = Version.valueOf("1.0.0+build.2");

int result = Version.BUILD_AWARE_ORDER.compare(v1, v2);  // < 0

int result = v1.compareWithBuildsTo(v2);  // < 0
boolean result = v1.equals(v2);           // false

TODO

• implement ranges

License

Java SemVer is licensed under the MIT License - see the LICENSE file for details.