September 2017 Update

Task/Array-concatenation/Java/array-concatenation-1.java

@@ -1,9 +0,0 @@
-public static Object[] objArrayConcat(Object[] o1, Object[] o2)
-{
-  Object[] ret = new Object[o1.length + o2.length];
-
-  System.arraycopy(o1, 0, ret, 0, o1.length);
-  System.arraycopy(o2, 0, ret, o1.length, o2.length);
-
-  return ret;
-}

Task/Array-concatenation/Java/array-concatenation-2.java

@@ -1,4 +0,0 @@
-Collection list1, list2, list1And2;
-//...list1 and list2 are instantiated...
-list1And2 = new ArrayList(list1); //or any other Collection you want
-list1And2.addAll(list2);

Task/Array-concatenation/Java/array-concatenation.java

@@ -0,0 +1,8 @@
+public static Object[] concat(Object[] arr1, Object[] arr2) {
+    Object[] res = new Object[arr1.length + arr2.length];
+
+    System.arraycopy(arr1, 0, res, 0, arr1.length);
+    System.arraycopy(arr2, 0, res, arr1.length, arr2.length);
+
+    return res;
+}