iammert

public interface Engine {
    void turnOn();
    void turnOff();
}

iammert

public class LPGEngine implements Engine {

    @Override
    public void turnOn() {
        //LPG Engine turned on.
    }

    @Override
    public void turnOff() {
        //LPG Engine turned off.

iammert

public class PetrolEngine implements Engine {

    @Override
    public void turnOn() {
        //Petrol Engine turned on.
    }

    @Override
    public void turnOff() {
        //Petrol Engine turned off.

iammert

public class Main {

    public static void main(String[] args){
        
        Engine petrolEngine = new PetrolEngine();
        
        Car car = new Car(petrolEngine);
        car.start();
        car.stop();
    }

iammert

public class Main {
 
    public static void main(String[] args){
        
        //Engine petrolEngine = new PetrolEngine();
        Engine lpg = new LPGEngine();
        
        Car car = new Car(lpg);
        car.start();
        car.stop();

iammert

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:1.2.3'
        classpath 'com.neenbedankt.gradle.plugins:android-apt:1.4'

iammert

...
apply plugin: 'com.neenbedankt.android-apt'

...

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])

    apt 'com.google.dagger:dagger-compiler:2.0'
    compile 'com.google.dagger:dagger:2.0'

iammert

public interface Engine {
    void turnOn();
    void turnOff();
}

iammert

public interface Car {
    void start();
    void stop();
}

iammert

public class LPGEngine implements Engine {

    @Override
    public void turnOn() {
        Log.v("DaggerExample", "LPG Engine turned on");
    }

    @Override
    public void turnOff() {
        Log.v("DaggerExample", "LPG Engine turned off.");