--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/BlackNode.java	Tue Aug 11 08:16:07 2015 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/BlackNode.java	Tue Sep 01 05:04:38 2015 +0900
@@ -83,8 +83,8 @@
         return false;
     }
 
-
     @Override
+    @SuppressWarnings("unchecked")
     public Node<K, V> replaceNode(Node<K, V> parent, Comparator ctr) throws RotateParent {
         Node<K, V> newNode;
         if (!this.left().isNotEmpty() && !this.right().isNotEmpty()) { //自身を削除する
@@ -115,7 +115,7 @@
                     return leftSubTreeNode.deleteBalance(newParent, ctr);
                 }
             } else {
-                Node<K, V> leftSubTreeNode = null;
+                Node<K, V> leftSubTreeNode;
                 try {
                     leftSubTreeNode = this.left().replaceNode(this, ctr);//右の子がいなかった場合、左の子を昇格させるだけで良い。
                     return createNode(this.left().getKey(), this.left().getValue(), leftSubTreeNode, this.right());

--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/DefaultComparator.java	Tue Aug 11 08:16:07 2015 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/DefaultComparator.java	Tue Sep 01 05:04:38 2015 +0900
@@ -2,11 +2,9 @@
 
 import java.util.Comparator;
 
-/**
- * Created by e115731 on 15/08/10.
- */
 public class DefaultComparator<K> implements Comparator<K>{
     @Override
+    @SuppressWarnings("unchecked")
     public int compare(K key, K compareKey) {
         return ((Comparable<? super K>)key).compareTo(compareKey);
     }

--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/Node.java	Tue Aug 11 08:16:07 2015 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/Node.java	Tue Sep 01 05:04:38 2015 +0900
@@ -79,6 +79,7 @@
 
     }
 
+    @SuppressWarnings("unchecked")
     public Node<K, V> delete(K key, Node<K, V> parent, Comparator ctr, Rotate side) throws RotateParent {
         if (this.isNotEmpty()) {
             int result = compare(key, ctr);
@@ -120,7 +121,7 @@
         return null; // no key
     }
 
-
+    @SuppressWarnings("unchecked")
     public Node<K, V> deleteSubTreeMaxNode(Node<K, V> parent, Comparator ctr, Rotate side) throws RotateParent {
         Node<K, V> node;
         try {

--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/RedNode.java	Tue Aug 11 08:16:07 2015 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/RedNode.java	Tue Sep 01 05:04:38 2015 +0900
@@ -55,6 +55,7 @@
         return true;
     }
 
+    @SuppressWarnings("unchecked")
     @Override
     public Node<K, V> replaceNode(Node<K, V> parent, Comparator ctr) throws RotateParent {
         Node<K, V> newNode;

--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/RotateParent.java	Tue Aug 11 08:16:07 2015 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/RotateParent.java	Tue Sep 01 05:04:38 2015 +0900
@@ -1,5 +1,8 @@
 package jp.ac.u_ryukyu.ie.cr.jungle.data.treemap;
 
+/**
+ * Generic Exception not support
+ **/
 public class RotateParent extends Exception {
 
     Node parent;
@@ -10,4 +13,4 @@
     public Node getParent() {
         return parent;
     }
-}
+}
\ No newline at end of file

--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/TreeMap.java	Tue Aug 11 08:16:07 2015 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/data/treemap/TreeMap.java	Tue Sep 01 05:04:38 2015 +0900
@@ -11,7 +11,7 @@
 
 public class TreeMap<K, V> {
     final Node<K, V> root;
-    Comparator comparator;
+    final Comparator comparator;
 
     public TreeMap() {
         this.root = new EmptyNode<>();
@@ -33,20 +33,15 @@
     }
 
     public Optional<V> get(final K key) {
-        return root.get(key, comparator);
+        return root.get(key, this.comparator);
     }
 
     public TreeMap<K, V> put(K key, V value) {
-
-        if (key == null || value == null)  // null check
-            throw new NullPointerException();
-
         if (isEmpty()) {
             Node<K, V> newRoot = new BlackNode<>(key, value, new EmptyNode<>(), new EmptyNode<>());
             return new TreeMap<>(newRoot, this.comparator);
         }
-
-        Node<K, V> newEntry = root.put(key, value, comparator);
+        Node<K, V> newEntry = root.put(key, value, this.comparator);
         Node<K, V> newRoot = new BlackNode<>(newEntry.getKey(), newEntry.getValue(), newEntry.left(), newEntry.right());
         return new TreeMap<>(newRoot, this.comparator);
     }