9.11.2021 |

Behavior driven development with java and cucumber

Behaviour Driven Development (BDD) is a software development process that originated from the Test driven development (TDD). Requirements, behaviour and results of the software are specified in a domain specific language that can be used by all stakeholders of the project. With this approach nearly everyone should be able to define the behaviour of the software prior to development in a way that is usable for a programmer.

Pitfalls while trying to introduce cucumber and spring in my current project:

Cucumber has a spring implementation, however it is not executing tests with the SpringRunner. Instead it uses a specific CucumberRunner that does not trigger TestExecutionListeners. With this restriction there is for example no trivial solution to trigger flyway migration scripts with integration tests.

Example with cucumber:

Feature definition with a domain specific language called gherkin:

Feature: Programming and Coffe
  As a project manager
  I want to know how much coffee my programmers consume

  Scenario: Programmer with low coffee consumption
    Given I employ a Programmer who drinks 200ml of coffe per hour
    When He works for 5 hours
    Then He drinks 1000ml of coffee

  Scenario: Programmer with high coffee consumption
    Given I employ a Programmer who drinks 500ml of coffe per hour
    When He works for 6 hours
    Then He drinks 3000ml of coffee

Implementation

public class MyStepdefs {
    Programmer programmer;
    int amount;

    @Given("I employ a Programmer who drinks {int}ml of coffe per hour")
    public void iEmployAProgrammerWhoDrinksMlOfCoffePerHour(int mlOfcoffeePerHour) {
        this.programmer = new Programmer(mlOfcoffeePerHour);
    }


    @When("He works for {int} hours")
    public void heWorksForHours(int hoursWorked) {
        this.amount = programmer.calculateAmountOfCoffeeConsumed(hoursWorked);
    }

    @Then("He drinks {int}ml of coffee")
    public void heDrinksMlOfCoffee(int amount) {
        this.amount = amount;
    }
}

Result

CucmberResult

There is by the way a possibility to make cucumber work with groovy:

import app.Programmer
import groovy.transform.Field

import static io.cucumber.groovy.EN.*

@Field programmer
@Field result


Given(~/^I employ a Programmer who drinks (\d+)ml of coffe per hour$/) { int mlOfcoffeePerHour ->
    this.programmer = new Programmer(mlOfcoffeePerHour)
}
When(~/^He works for (\d+) hours$/) { int hoursWorked ->
    result = programmer.calculateAmountOfCoffeeConsumed(hoursWorked)
}
Then(~/^He drinks (\d+)ml of coffee$/) { int amount ->
    result == amount
}
Zur Übersicht
Michael Virks

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Jörg Herbst

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Sven Röttering

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Hallo, ich bin Jörg Herbst!

Ich bin der CEO von newcubator und freue mich über jede Nachricht!

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