impl: custom linked list size and add

assignment/src/main/java/appointmentplanner/customlist/CustomLinkedListImpl.java

@@ -0,0 +1,84 @@
+package appointmentplanner.customlist;
+
+import java.util.Iterator;
+
+import appointmentplanner.customlist.api.CustomLinkedList;
+
+public class CustomLinkedListImpl<T> implements CustomLinkedList<T> {
+
+  CustomLinkedListNode<T> head = null;
+
+  @Override
+  public Iterator<T> iterator() {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'iterator'");
+  }
+
+  @Override
+  public void add(T item) {
+    CustomLinkedListNode<T> newNode = new CustomLinkedListNode<>(item);
+
+    CustomLinkedListNode<T> oldHead = head;
+
+    head = newNode;
+
+    if (oldHead != null) {
+      head.setNext(oldHead);
+    }
+  }
+
+  @Override
+  public void remove(T item) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'remove'");
+  }
+
+  @Override
+  public void insertAfter(T reference, T item) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'insertAfter'");
+  }
+
+  @Override
+  public void insertBefore(T reference, T item) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'insertBefore'");
+  }
+
+  @Override
+  public T getAfter(T reference) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'getAfter'");
+  }
+
+  @Override
+  public T getBefore(T reference) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'getBefore'");
+  }
+
+  @Override
+  public boolean contains(T item) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'contains'");
+  }
+
+  private int recursiveSizeCalc(CustomLinkedListNode<T> node, int count) {
+    if (node == null) {
+      return 0;
+    }
+
+    if (node.getNext() == null) {
+      return count;
+    }
+
+    return recursiveSizeCalc(node.getNext(), count + 1);
+
+  }
+
+  @Override
+  public int size() {
+    return recursiveSizeCalc(this.head, 1);
+  }
+
+}