update,

_resources/it114105/itp4507/Assignment/19-20/src/StateManager.java

@@ -0,0 +1,36 @@
+
+import java.util.Stack;
+
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+
+/**
+ *
+ * @author jerrykwok
+ */
+public class StateManager {
+    private Stack redoList;
+    private Stack undoList;
+    private Caretaker caretaker;
+    
+    
+    public StateManager() {
+        undoList = new Stack<>();
+        redoList = new Stack<>();
+        caretaker = new Caretaker();
+    }
+    
+    public Caretaker getCaretaker(){
+        return caretaker;
+    }
+    public Stack getUndoList() {
+        return undoList;
+    }
+
+    public Stack getRedoList() {
+        return redoList;
+    }
+}