Change configurable factory to registry

src/aliensimulator/AlienSimulator.java

@@ -16,6 +16,13 @@ import aliensimulator.verhalten.ErdeNeutralAdapter;
 public class AlienSimulator {
 	
 	public static void main(String[] args) {
+		try {
+			Class.forName("aliensimulator.predators.HishQuTen");
+			Class.forName("aliensimulator.predators.Yautja");
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+
 		AlienFactory alienFactory = new AlienFactory();
 
 		Alien alienMars = alienFactory.createAlien("mars");

src/aliensimulator/predators/HishQuTen.java

@@ -5,6 +5,10 @@ import aliensimulator.verhalten.ErdeNeutralAdapter;
 
 public class HishQuTen extends Predator {
 
+	static {
+		PredatorRegistry.register(new HishQuTen());
+	}
+
 	public HishQuTen() {
 		this.setErdeBesuchverhalten(new ErdeNeutralAdapter(new NeutralBesuchen()));
 	}
@@ -14,4 +18,8 @@ public class HishQuTen extends Predator {
 		System.out.println("Ich bin ein Hish-Qu-Ten.");
 	}
 
+	@Override
+	public Boolean canHandle(String type) {
+		return type.equalsIgnoreCase("hishquten");
+	}
 }

src/aliensimulator/predators/Predator.java

@@ -7,6 +7,8 @@ public abstract class Predator {
 
     public abstract void darstellen();
 
+    public abstract Boolean canHandle(String type);
+
     public void fliegen() {
         System.out.println("Ich fliege durch den Weltraum.");
     }

src/aliensimulator/predators/PredatorFactory.java

 package aliensimulator.predators;
 
-
-import java.io.IOException;
-import java.util.Properties;
-
 public class PredatorFactory {
 
 	public Predator createPredator(String type) {
 		Predator predator = null;
-		Properties properties = new Properties();
 
-		try {
-			properties.load(this.getClass().getResourceAsStream("predator.properties"));
-			String className = properties.getProperty(type);
-			Class<?> classOfPredator = Class.forName(className);
-			predator = (Predator) classOfPredator.newInstance();
-		} catch (IOException | ClassNotFoundException | InstantiationException | IllegalAccessException e) {
-			e.printStackTrace();
+		predator = PredatorRegistry.getPredatorHandler(type);
+		if (predator == null) {
+			System.out.println("Kein Handler gefunden");
 		}
+
 		return predator;
 	}
 }

src/aliensimulator/predators/PredatorRegistry.java

+package aliensimulator.predators;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.ListIterator;
+
+public class PredatorRegistry {
+    static List<Predator> predatorHandlers = new ArrayList<Predator>();
+
+    static void register(Predator predator) {
+        predatorHandlers.add(predator);
+    }
+
+    static Predator getPredatorHandler(String type) {
+        ListIterator<Predator> iter = predatorHandlers.listIterator();
+        while (iter.hasNext()) {
+            Predator predator = iter.next();
+            if (predator.canHandle(type)) {
+                return predator;
+            }
+        }
+        return null;
+    }
+
+}

src/aliensimulator/predators/Yautja.java

@@ -5,6 +5,10 @@ import aliensimulator.verhalten.ErdeZerstoererischAdapter;
 
 public class Yautja extends Predator {
 
+	static {
+		PredatorRegistry.register(new Yautja());
+	}
+
 	public Yautja() {
 		this.setErdeBesuchverhalten(new ErdeZerstoererischAdapter());
 	}
@@ -14,4 +18,8 @@ public class Yautja extends Predator {
 		System.out.println("Ich bin ein Yautja.");
 	}
 
+	@Override
+	public Boolean canHandle(String type) {
+		return type.equalsIgnoreCase("yautja");
+	}
 }

src/aliensimulator/predators/predator.properties

-yautja=aliensimulator.predators.Yautja
-hishquten=aliensimulator.predators.HishQuTen