The Unleash Client 4 Java

Create a new a Unleash instance

It is really easy to get a new instance of Unleash. In your app you typically just want one instance, and inject that where you need it. You will typically use a dependency injection frameworks such as
Spring or Guice to manage this.

You create a new instance with the following command:

URI unleashServer = URI.create("http://unleash.herokuapp.com/features")
Unleash unleash = new DefaultUnleash(unleashServer);

Awesome feature toggle API

It is really simple to use unleash.

if(unleash.isEnabled("AwesomeFeature")) {
  //do some magic
} else {
  //do old boring stuff
}

Calling unleash.isEnabled("AwesomeFeature") is the equvivalent of calling unleash.isEnabled("AwesomeFeature", false). Which means that it will return false if it cannot find the named toggle.

If you want it to default to true, you can pass true as the second argument:

unleash.isEnabled("AwesomeFeature", true)

By default unleash-client fetches the feature toggles from unleash-server every 10s, and stores the result in unleash-repo.json which is located in the java.io.tmpdir directory. This means that if the unleash-server becomes unavailable, the unleash-client will still be able to toggle the features based on the values stored in unleash-repo.json. As a result of this, the second argument of isEnabled will be returned in two cases:

• When unleash-repo.json does not exists
• When the named feature toggle does not exist in unleash-repo.json

Development

Build:

mvn clean install

Cobertura coverage reports:

mvn cobertura:cobertura -DcoberturaFormat=html

The generated report will be available at target/site/cobertura/index.html