Hamcrest Optional

An extension to Java Hamcrest which provides matchers for java.util.Optional.

Maven Dependency

Version 2.0.0 - Latest

Changes

Methods renamed from hasValue to isPresentAndIs/isPresentAnd for better fluency.

<dependencies>
...
<dependency>
  <groupId>com.github.npathai</groupId>
  <artifactId>hamcrest-optional</artifactId>
  <version>2.0.0</version>
</dependency>
...
</dependencies>

Version 1.0

<dependencies>
...
<dependency>
  <groupId>com.github.npathai</groupId>
  <artifactId>hamcrest-optional</artifactId>
  <version>1.0</version>
</dependency>
...
</dependencies>

Usage

hamcrest-optional provides four matchers for Optional: isEmpty(), isPresent(), isPresentAndIs(Object) and isPresentAnd(Matcher).

isEmpty()

This matcher matches when the examined Optional contains no value.

import static com.github.npathai.hamcrestopt.OptionalMatchers.isEmpty;

Optional<Object> optional = Optional.empty();
assertThat(optional, isEmpty());

isPresent()

This matcher matches when the examined Optional contains a value.

import static com.github.npathai.hamcrestopt.OptionalMatchers.isPresent;

Optional<String> optional = Optional.of("dummy value");
assertThat(optional, isPresent());

isPresentAndIs(Object)

This matcher matches when the examined Optional contains a value that is logically equal to the specified object.

import static com.github.npathai.hamcrestopt.OptionalMatchers.isPresentAndIs;

Optional<String> optional = Optional.of("dummy value");
assertThat(optional, isPresentAndIs("dummy value"));

isPresentAnd(Matcher)

This matcher matches when the examined Optional contains a value that satisfies the specified matcher.

import static com.github.npathai.hamcrestopt.OptionalMatchers.isPresentAnd;
import static org.hamcrest.Matchers.startsWith;

Optional<String> optional = Optional.of("dummy value");
assertThat(optional, isPresentAnd(startsWith("dummy")));

Development Guide

hamcrest-optional is build with Maven. If you want to contribute code then

Please write a test for your change.
Ensure that you don't break the build by running mvn verify -Dgpg.skip.
Fork the repo and create a pull request. (See Understanding the GitHub Flow)

hamcrest-optional supports Travis CI for continuous integration. Your pull request is automatically build by Travis CI.

Release Guide

Select a new version according to the Semantic Versioning 2.0.0 Standard.
Set the new version in pom.xml.
Commit the modified pom.xml.
Push the commit: git push origin master
Run mvn clean deploy with JDK 8.
Add a tag for the release: git tag hamcrest-optional-X.X.X
Push the tag: git push origin hamcrest-optional-X.X.X

npathai / hamcrest-optional