Fix bugs, clean the code and add unit tests.

simple-factory/etc/simple-factory.urm.puml

@@ -0,0 +1,35 @@
+@startuml
+package com.iluwatar.simplefactory {
+  class App {
+    - LOGGER : Logger {static}
+    + App()
+    + main(args : String[]) {static}
+  }
+  interface Car {
+    + getDescription() : String {abstract}
+  }
+  class CarSimpleFactory {
+    + CarSimpleFactory()
+    + getCar(type : CarType) : Car {static}
+  }
+  ~enum CarType {
+    + FERRARI {static}
+    + FORD {static}
+    + valueOf(name : String) : CarType {static}
+    + values() : CarType[] {static}
+  }
+  class Ferrari {
+    ~ DESCRIPTION : String {static}
+    + Ferrari()
+    + getDescription() : String
+  }
+  class Ford {
+    ~ DESCRIPTION : String {static}
+    + Ford()
+    + getDescription() : String
+  }
+}
+CarType ..+ CarSimpleFactory
+Ferrari ..|> Car 
+Ford ..|> Car 
+@enduml

simple-factory/pom.xml

@@ -6,6 +6,17 @@
     <version>1.24.0-SNAPSHOT</version>
   </parent>
   <artifactId>simple-factory</artifactId>
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+    </dependency>
+  </dependencies>
   <build>
 		<plugins>
 			<!-- Maven assembly plugin is invoked with default setting which we have 
@@ -18,7 +29,7 @@
 						<configuration>
 							<archive>
 								<manifest>
-									<mainClass>com.iluwatar.abstractfactory.App</mainClass>
+									<mainClass>com.iluwatar.simplefactory.App</mainClass>
 								</manifest>
 							</archive>
 						</configuration>

simple-factory/src/main/java/com/iluwatar/simplefactory/App.java

@@ -1,3 +1,26 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
 package com.iluwatar.simplefactory;
 
 import org.slf4j.Logger;
@@ -5,12 +28,15 @@ import org.slf4j.LoggerFactory;
 
 public class App {
   
-	private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
+  private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
   
-	public static void main(String[] args) {
+  /**
-		Car car1 = CarSimpleFactory.getCar(CarSimpleFactory.carTypes.FORD);
+   * Program main entry point.
-		Car car2 = CarSimpleFactory.getCar(CarSimpleFactory.carTypes.FERRARI);
+   */
-		LOGGER.info(car1.getDescription());
+  public static void main(String[] args) {
-		LOGGER.info(car2.getDescription());
+    Car car1 = CarSimpleFactory.getCar(CarSimpleFactory.CarType.FORD);
-	}
+    Car car2 = CarSimpleFactory.getCar(CarSimpleFactory.CarType.FERRARI);
+    LOGGER.info(car1.getDescription());
+    LOGGER.info(car2.getDescription());
+  }
 }

simple-factory/src/main/java/com/iluwatar/simplefactory/Car.java

@@ -1,10 +1,10 @@
 package com.iluwatar.simplefactory;
 
 /**
- * Car interface
+ * Car interface.
  */
 public interface Car {
   
-	public String getDescription();
+  public String getDescription();
   
 }

simple-factory/src/main/java/com/iluwatar/simplefactory/CarSimpleFactory.java

@@ -1,29 +1,25 @@
 package com.iluwatar.simplefactory;
 
-
 /**
- * Factory of cars
+ * Factory of cars.
  */
 public class CarSimpleFactory {
   
-	/*
+  /**
-	 * Enumeration for different types of cars
+   * Enumeration for different types of cars.
-	 */
+   */
-	static enum carTypes {
+  static enum CarType {
-		FORD, FERRARI
+    FORD, FERRARI
-	};
+  }
   
-	/*
+  /**
-	 * Factory method takes as parameter a car type and initiate the appropriate class
+   * Factory method takes as parameter a car type and initiate the appropriate class.
-	 */
+   */
-	public static Car getCar(carTypes type) {
+  public static Car getCar(CarType type) {
-		switch (type) {
+    switch (type) {
-		case FORD:
+      case FORD: return new Ford();
-			return new Ford();
+      case FERRARI: return new Ferrari();
-		case FERRARI:
+      default: throw new IllegalArgumentException("Model not supported.");
-			return new Ferrari();
+    }
-		default:
+  }
-			throw new IllegalArgumentException("Model not supported.");
-		}
-	}
 }

simple-factory/src/main/java/com/iluwatar/simplefactory/Ferrari.java

@@ -1,14 +1,14 @@
 package com.iluwatar.simplefactory;
 
 /**
- * Ferrari implementation
+ * Ferrari implementation.
  */
 public class Ferrari implements Car {
    
-	static final String DESCRIPTION = "This is Ferrari.";
+  static final String DESCRIPTION = "This is Ferrari.";
 
-	@Override
+  @Override
-	public String getDescription() {
+  public String getDescription() {
-		return DESCRIPTION;
+    return DESCRIPTION;
-	}
+  }
 }

simple-factory/src/main/java/com/iluwatar/simplefactory/Ford.java

@@ -1,14 +1,14 @@
 package com.iluwatar.simplefactory;
 
 /**
- * Ford implementation
+ * Ford implementation.
  */
 public class Ford implements Car {
 
-	static final String DESCRIPTION = "This is Ford.";
+  static final String DESCRIPTION = "This is Ford.";
 
-	@Override
+  @Override
-	public String getDescription() {
+  public String getDescription() {
-		return DESCRIPTION;
+    return DESCRIPTION;
-	}
+  }
 }

simple-factory/src/test/java/com/iluwatar/simplefactory/AppTest.java

@@ -0,0 +1,14 @@
+package com.iluwatar.simplefactory;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class AppTest {
+
+	@Test
+	void shouldExecuteWithoutExceptions() {
+		assertDoesNotThrow(() -> App.main(new String[]{}));
+	}
+
+}

simple-factory/src/test/java/com/iluwatar/simplefactory/CarSimpleFactoryTest.java

@@ -0,0 +1,15 @@
+package com.iluwatar.simplefactory;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class CarSimpleFactoryTest {
+
+	@Test
+	void shouldReturnFerrariInstance() {
+		final var ferrari = CarSimpleFactory.getCar(CarSimpleFactory.CarType.FERRARI);
+		assertTrue(ferrari instanceof Ferrari);
+	}
+
+}