Interface vs Abstract Class in Java

core-java-modules/core-java-lang-oop-patterns/README.md

@@ -7,3 +7,4 @@ This module contains articles about Object-oriented programming (OOP) patterns i
 - [Inheritance and Composition (Is-a vs Has-a relationship) in Java](https://www.baeldung.com/java-inheritance-composition)
 - [Immutable Objects in Java](https://www.baeldung.com/java-immutable-object)
 - [How to Make a Deep Copy of an Object in Java](https://www.baeldung.com/java-deep-copy)
+- [Interface vs Abstract Class in Java](https://www.baeldung.com/interface-vs-abstract-class-in-java/)

core-java-modules/core-java-lang-oop-patterns/src/main/java/com/baeldung/interface_vs_abstract_class/Car.java

@@ -0,0 +1,42 @@
+package com.baeldung.interface_vs_abstract_class;
+
+public class Car extends Vehicle {
+
+	public Car(String vechicleName) {
+		super(vechicleName);
+	}
+
+	public Car(String vechicleName, String vehicleModel) {
+		super(vechicleName, vehicleModel);
+	}
+
+	public Car(String vechicleName, String vehicleModel, Long makeYear) {
+		super(vechicleName, vehicleModel, makeYear);
+	}
+
+	@Override
+	protected void start() {
+		// code implementation details on starting a car.
+	}
+
+	@Override
+	protected void stop() {
+		// code implementation details on stopping a car.
+	}
+
+	@Override
+	protected void drive() {
+		// code implementation details on start driving a car.
+	}
+
+	@Override
+	protected void changeGear() {
+		// code implementation details on changing the car gear.
+	}
+
+	@Override
+	protected void reverse() {
+		// code implementation details on reverse driving a car.
+	}
+
+}

core-java-modules/core-java-lang-oop-patterns/src/main/java/com/baeldung/interface_vs_abstract_class/ImageSender.java

@@ -0,0 +1,12 @@
+package com.baeldung.interface_vs_abstract_class;
+
+import java.io.File;
+
+public class ImageSender implements Sender {
+
+	@Override
+	public void send(File fileToBeSent) {
+		// image sending implementation code.
+	}
+
+}

core-java-modules/core-java-lang-oop-patterns/src/main/java/com/baeldung/interface_vs_abstract_class/Sender.java

@@ -0,0 +1,8 @@
+package com.baeldung.interface_vs_abstract_class;
+
+import java.io.File;
+
+public interface Sender {
+
+	void send(File fileToBeSent);
+}

core-java-modules/core-java-lang-oop-patterns/src/main/java/com/baeldung/interface_vs_abstract_class/Vehicle.java

@@ -0,0 +1,57 @@
+package com.baeldung.interface_vs_abstract_class;
+
+public abstract class Vehicle {
+
+	private String vehicleName;
+	private String vehicleModel;
+	private Long makeYear;
+
+	public Vehicle(String vehicleName) {
+		this.vehicleName = vehicleName;
+	}
+
+	public Vehicle(String vehicleName, String vehicleModel) {
+		this(vehicleName);
+		this.vehicleModel = vehicleModel;
+	}
+
+	public Vehicle(String vechicleName, String vehicleModel, Long makeYear) {
+		this(vechicleName, vehicleModel);
+		this.makeYear = makeYear;
+	}
+
+	public String getVehicleName() {
+		return vehicleName;
+	}
+
+	public void setVehicleName(String vehicleName) {
+		this.vehicleName = vehicleName;
+	}
+
+	public String getVehicleModel() {
+		return vehicleModel;
+	}
+
+	public void setVehicleModel(String vehicleModel) {
+		this.vehicleModel = vehicleModel;
+	}
+
+	public Long getMakeYear() {
+		return makeYear;
+	}
+
+	public void setMakeYear(Long makeYear) {
+		this.makeYear = makeYear;
+	}
+
+	protected abstract void start();
+
+	protected abstract void stop();
+
+	protected abstract void drive();
+
+	protected abstract void changeGear();
+
+	protected abstract void reverse();
+
+}

core-java-modules/core-java-lang-oop-patterns/src/main/java/com/baeldung/interface_vs_abstract_class/VideoSender.java

@@ -0,0 +1,13 @@
+package com.baeldung.interface_vs_abstract_class;
+
+import java.io.File;
+
+public class VideoSender implements Sender {
+
+	@Override
+	public void send(File fileToBeSent) {
+		// video sending implementation code
+		System.out.println("Sending Video...");
+	}
+
+}

core-java-modules/core-java-lang-oop-patterns/src/test/java/com/baeldung/interface_vs_abstract_class/SenderUnitTest.java

@@ -0,0 +1,21 @@
+package com.baeldung.interface_vs_abstract_class;
+
+import static org.junit.jupiter.api.Assertions.*;
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+
+class SenderUnitTest {
+
+	public final static String IMAGE_FILE_PATH = "/sample_image_file_path/photo.jpg";
+
+	@Test
+	void givenImageUploaded_whenButtonClicked_thenSendImage() {
+
+		File imageFile = new File(IMAGE_FILE_PATH);
+
+		Sender sender = new ImageSender();
+		sender.send(imageFile);
+	}
+
+}

core-java-modules/core-java-lang-oop-patterns/src/test/java/com/baeldung/interface_vs_abstract_class/VehicleUnitTest.java

@@ -0,0 +1,21 @@
+package com.baeldung.interface_vs_abstract_class;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class VehicleUnitTest {
+
+	@Test
+	void givenVehicle_whenNeedToDrive_thenStart() {
+
+		Vehicle car = new Car("BMW");
+
+		car.start();
+		car.drive();
+		car.changeGear();
+		car.stop();
+
+	}
+
+}