Mockito Cookbook

Injecting test doubles instead of beans with Guice

In this recipe, we will replace an existing bean with a test double using Guice's (https://code.google.com/p/google-guice/) module configuration.

Getting ready

Let's assume that our system under test is the tax transferring system for a given person, as shown in the following code:

public class TaxTransferer {

    private final TaxService taxService;

    public TaxTransferer(TaxService taxService) {
        this.taxService = taxService;
    }

    public boolean transferTaxFor(Person person) {
        if (person == null) {
            return false;
        }
        taxService.transferTaxFor(person);
        return true;
    }

}

Where the TaxService class is an interface that has an implementation called TaxWebService, which makes the web service call, as shown in the ...