BAEL-376 - changing method signatures

core-java/src/main/java/com/baeldung/generics/Building.java

@@ -7,6 +7,6 @@ public class Building {
 	private static final Logger LOGGER = LoggerFactory.getLogger(Building.class);
 
 	public void paint() {
-		LOGGER.info("Building");
+		LOGGER.info("Painting Building");
 	}
 }

core-java/src/main/java/com/baeldung/generics/Generics.java

@@ -1,27 +1,34 @@
 package com.baeldung.generics;
 
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
+import java.util.function.Function;
 import java.util.stream.Collectors;
 
 public class Generics {
 
-	// definition of a generic method
-	public static <T> List<T> fromArrayToList(T[] a) {
-		return Arrays.stream(a).collect(Collectors.toList());
-	}
+    // definition of a generic method
+    public static <T> List<T> fromArrayToList(T[] a) {
+        return Arrays.stream(a).collect(Collectors.toList());
+    }
 
-	// example of a generic method that has Number as an upper bound for T
-	public static <T extends Number> List<T> fromArrayToListWithUpperBound(T[] a) {
-		return Arrays.stream(a).collect(Collectors.toList());
-	}
+    // definition of a generic method
+    public static <T, G> List<G> fromArrayToList(T[] a, List<G> list, Function<T, G> mapperFunction) {
+        List<T> listWithTypeT = Arrays.stream(a).collect(Collectors.toList());
+        return listWithTypeT.stream().map(mapperFunction)
+          .collect(Collectors.toList());
+    }
 
-	// example of a generic method with a wild card, this method can be used
-	// with a list of any subtype of Building
-	public static boolean paintAllBuildings(List<? extends Building> buildings) {
-		buildings.forEach(Building::paint);
-		return true;
-	}
+
+    // example of a generic method that has Number as an upper bound for T
+    public static <T extends Number> List<T> fromArrayToListWithUpperBound(T[] a) {
+        return Arrays.stream(a).collect(Collectors.toList());
+    }
+
+    // example of a generic method with a wild card, this method can be used
+    // with a list of any subtype of Building
+    public static void paintAllBuildings(List<? extends Building> buildings) {
+        buildings.forEach(Building::paint);
+    }
 
 }

core-java/src/main/java/com/baeldung/generics/House.java

@@ -7,6 +7,6 @@ public class House extends Building {
     private static final Logger LOGGER = LoggerFactory.getLogger(House.class);
 
     public void paint() {
-        LOGGER.info("House");
+        LOGGER.info("Painting House");
     }
 }