--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/store/index/Index.java	Sat Dec 31 02:21:05 2016 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/jungle/store/index/Index.java	Sat Dec 31 03:30:14 2016 +0900
@@ -117,4 +117,26 @@
         }
         return false;
     }
+
+    public boolean isEmpty() {
+        Iterator<String> indexListKeys = indexList.keys();
+        while (indexListKeys.hasNext()) {
+            String indexListKey = indexListKeys.next();
+            Optional<TreeMap<String, List<TreeNode>>> indexOp = indexList.get(indexListKey);
+            if (!indexOp.isPresent())
+                continue;
+            TreeMap<String,List<TreeNode>> index = indexOp.get();
+            Iterator<String> indexKeys = index.keys();
+            while(indexKeys.hasNext()) {
+                String indexKey = indexKeys.next();
+                Optional<List<TreeNode>> nodeListOp = index.get(indexKey);
+                if (!nodeListOp.isPresent())
+                    continue;
+                List<TreeNode> nodeList = nodeListOp.get();
+                if (nodeList.length() > 0)
+                    return false;
+            }
+        }
+        return true;
+    }
 }

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/test/java/jp/ac/u_ryukyu/ie/cr/jungle/index/difference/IndexTest.java	Sat Dec 31 03:30:14 2016 +0900
@@ -0,0 +1,103 @@
+package jp.ac.u_ryukyu.ie.cr.jungle.index.difference;
+
+import jp.ac.u_ryukyu.ie.cr.jungle.DefaultJungle;
+import jp.ac.u_ryukyu.ie.cr.jungle.Jungle;
+import jp.ac.u_ryukyu.ie.cr.jungle.core.Attributes;
+import jp.ac.u_ryukyu.ie.cr.jungle.core.Children;
+import jp.ac.u_ryukyu.ie.cr.jungle.store.index.Index;
+import jp.ac.u_ryukyu.ie.cr.jungle.store.index.ParentIndex;
+import jp.ac.u_ryukyu.ie.cr.jungle.store.nodepath.DefaultNodePath;
+import jp.ac.u_ryukyu.ie.cr.jungle.store.nodepath.NodePath;
+import jp.ac.u_ryukyu.ie.cr.jungle.transaction.editor.jungleTreeEditor.JungleTreeEditor;
+import jp.ac.u_ryukyu.ie.cr.jungle.transaction.node.TreeNode;
+import jp.ac.u_ryukyu.ie.cr.jungle.traverser.DefaultTraverser;
+import jp.ac.u_ryukyu.ie.cr.jungle.tree.JungleTree;
+import jp.ac.u_ryukyu.ie.cr.jungle.util.Either;
+import jp.ac.u_ryukyu.ie.cr.jungle.util.Error.Error;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.nio.ByteBuffer;
+import java.util.Iterator;
+
+/**
+ * Created by e115731 on 2016/12/31.
+ */
+public class IndexTest {
+    private Index index;
+
+    @Test
+    public void Index() {
+        Jungle jungle = new DefaultJungle(null, "hogehoge", new DefaultTraverser());
+        jungle.createNewTree("tree");
+        JungleTree tree = jungle.createNewDifferenceTree("Tree");
+        JungleTreeEditor editor = tree.getJungleTreeEditor();
+        NodePath path = new DefaultNodePath();
+        for (int j = 0; j < 10; j++) { //木の構築
+            Either<Error, JungleTreeEditor> either = editor.addNewChildAt(path, 0);
+            Assert.assertFalse(either.isA());
+            editor = either.b();
+            either = editor.putAttribute(path, "key", ByteBuffer.wrap(path.toString().getBytes()));
+            Assert.assertFalse(either.isA());
+            editor = either.b();
+            path = path.add(0);
+        }
+        Either<Error, JungleTreeEditor> either = editor.success();
+        Assert.assertFalse(either.isA());
+        editor = either.b();
+
+        index = tree.getIndex();
+        TreeNode root = tree.getRootNode();
+        checkIndex(root);//indexが張られているかを調べる
+        Assert.assertTrue(index.isEmpty());
+
+
+        //一回木を更新する
+        editor = tree.getJungleTreeEditor();
+        path = new DefaultNodePath();
+        either = editor.addNewChildAt(path, 0);
+        Assert.assertFalse(either.isA());
+        editor = either.b();
+        either = editor.putAttribute(path, "key", ByteBuffer.wrap(path.toString().getBytes()));
+        Assert.assertFalse(either.isA());
+        editor = either.b();
+        either = editor.success();
+        Assert.assertFalse(either.isA());
+
+        //更新後にちゃんとIndexが貼れているかを調べる
+        index = tree.getIndex();
+        root = tree.getRootNode();
+        checkIndex(root);
+        Assert.assertTrue(index.isEmpty());
+
+        Either<Error, JungleTree> oldTreeEither = tree.getOldTree(1);
+        Assert.assertFalse(oldTreeEither.isA());
+        JungleTree oldTree = oldTreeEither.b(); //過去のTreeのIndexが上書きされてないかを調べる
+        ParentIndex oldTreeParentIndex = oldTree.getParentIndex();
+        index = tree.getIndex();
+        Assert.assertNotEquals(oldTreeParentIndex, index);
+    }
+
+    public void checkIndex(TreeNode currentNode) {
+        Children children = currentNode.getChildren();
+        for (TreeNode child : children) {
+            checkIndex(child);
+        }
+
+        Attributes attribute = currentNode.getAttributes();
+        Iterator<String> keys = attribute.getKeys();
+        while (keys.hasNext()) {
+            String key = keys.next();
+            String value = attribute.getString(key);
+            Iterator<TreeNode> nodeIterator = index.get(key, value);
+            boolean existNode = false;
+            while(nodeIterator.hasNext()) {
+                TreeNode node = nodeIterator.next();
+                if (node.equals(currentNode))
+                    existNode = true;
+            }
+            Assert.assertTrue(existNode);
+        }
+        index = index.delete(currentNode);
+    }
+}