Test NJ

Framework for JUnit test injection and lifecycle hooks based on JUnit 4 and Guice.

Getting Started

1. Add a Maven dependency to your project

<dependency>
  <groupId>com.polopoly</groupId>
  <artifactId>testNJ</artifactId>
  <version>${testNJ.version}</version>
</dependency>

2. Bindings

Craete a Guice module for your tests:

package com.myproject;

import com.google.inject.AbstractModule;

public class Module extends AbstractModule {

    @Override
    protected void configure() {
        bind(Duck.class).toInstance(new SwedishBlueDuck());
    }

}

TestNJ uses the Java Service Locator pattern to look for implementations of Guice modules in your projects (implementations of com.google.inject.Module).

Add a file named com.google.inject.Module in your project's META-INF/services folder, this file should contain the names of the Guice module implementation classes, in our example:

echo 'com.project.Module' > ${prj.root}/META-INF/services/com.google.inject.Module

3. Write your test

@RunWith(TestNJRunner.class)
public class SimpleInjectTest {

    @Inject
    private Duck duck;

    @Test
    public void duck_does_quack() {
        Assert.assertEquals("haloj", duck.quack());
    }

}

4. Use Callbacks

You can register test callbacks and have your custom code run before/after a single test run.

Simply implement your callback:

package com.myproject;

import com.polopoly.testnj.TestCallbacks;
import org.junit.runners.model.FrameworkMethod;
import org.junit.runners.model.Statement;

public class DummyTestCallbacks implements TestCallbacks {

    @Override
    public void before(FrameworkMethod method, Object target, Statement statement) {
        System.err.println("before");
    }

    @Override
    public void after(FrameworkMethod method, RunNotifier notifier) {
        System.err.println("after");
    }

}

... and register it in your Guice Module:

package com.myproject;

import com.google.inject.AbstractModule;

public class Module extends AbstractModule {

    @Override
    protected void configure() {
        bind(Duck.class).toInstance(new SwedishBlueDuck());
        TestNJContext.addCallback(new DummyTestCallbacks());
    }

}