September 2017 Update

Task/Memory-allocation/Kotlin/memory-allocation.kotlin

@@ -0,0 +1,30 @@
+// version 1.1.2
+
+class MyClass(val myInt: Int) {
+    // in theory this method should be called automatically prior to GC
+    protected fun finalize() {
+        println("MyClass being finalized...")
+    }
+}
+
+fun myFun() {
+    val mc: MyClass = MyClass(2)   // new non-nullable MyClass object allocated on the heap
+    println(mc.myInt)
+    var mc2: MyClass? = MyClass(3) // new nullable MyClass object allocated on the heap
+    println(mc2?.myInt)
+    mc2 = null                     // allowed as mc2 is nullable
+    println(mc2?.myInt)
+    // 'mc' and 'mc2' both become eligible for garbage collection here as no longer used
+}
+
+fun main(args: Array<String>) {
+    myFun()
+    Thread.sleep(3000)  // allow time for GC to execute
+    val i: Int  = 4     // new non-nullable Int allocated on stack
+    println(i)
+    var j: Int? = 5     // new nullable Int allocated on heap
+    println(j)
+    j = null            // allowed as 'j' is nullable
+    println(j)
+    // 'j' becomes eligible for garbage collection here as no longer used
+}