--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/DefaultJungleTree.java	Tue Nov 11 18:57:52 2014 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/DefaultJungleTree.java	Thu Nov 13 22:04:14 2014 +0900
@@ -1,12 +1,8 @@
 package jp.ac.u_ryukyu.ie.cr.shoshi.jungle;
 
-import java.util.concurrent.atomic.AtomicReference;
-
-import org.omg.CORBA.TCKind;
-
 import fj.data.List;
+import fj.data.Option;
 import fj.data.TreeMap;
-import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.persistent.ChangeList;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.persistent.ChangeListWriter;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.ChangeSet;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.NodePath;
@@ -16,85 +12,109 @@
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.AtomicReservableReference;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.DefaultJungleTreeEditor;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.DefaultTransactionManager;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.DefaultTreeContext;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.IndexJungleTreeEditor;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.TreeContext;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.traverser.InterfaceTraverser;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.DefaultEither;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.Either;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.Error;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.GetOldTreeError;
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.Pair;
 import jp.ac.u_ryukyu.ie.cr.tatsuki.jungle.store.index.IndexManager;
 
+public class DefaultJungleTree implements JungleTree {
+  private final AtomicReservableReference<TreeContext> repository;
+  private final String uuid;
+  private final ChangeListWriter writer;
+  private final TreeEditor editor;
 
-public class DefaultJungleTree implements JungleTree
-{
-	private final AtomicReservableReference<TreeContext> repository;
-	private final String uuid;
-	private final ChangeListWriter writer;
-	private final TreeEditor editor;
-	
-	public DefaultJungleTree(TreeContext tc,String uuid,ChangeListWriter writer,TreeEditor editor)
-	{
-		this.repository = new AtomicReservableReference<TreeContext>(tc);
-		this.uuid = uuid;
-		this.writer = writer;
-		this.editor = editor;
-	}
+  public DefaultJungleTree(TreeContext tc, String uuid, ChangeListWriter writer, TreeEditor editor) {
+    this.repository = new AtomicReservableReference<TreeContext>(tc);
+    this.uuid = uuid;
+    this.writer = writer;
+    this.editor = editor;
+  }
 
-	@Override
-	public JungleTreeEditor getTreeEditor()
-	{
-		TreeContext tc = repository.get();
-		DefaultTransactionManager txManager = new DefaultTransactionManager(writer,tc,repository,uuid);
-		TreeNode root = tc.getTreeNode();
-		TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> index = getIndex();
-		return new DefaultJungleTreeEditor(root,txManager,editor,index);
-	}
-	
-	@Override
-	public IndexJungleTreeEditor getIndexTreeEditor()
-	{
-		TreeContext tc = repository.get();
-		DefaultTransactionManager txManager = new DefaultTransactionManager(writer,tc,repository,uuid);
-		TreeNode root = tc.getTreeNode();
-		TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> newIndex = getIndex();
-		return new IndexJungleTreeEditor(root,txManager,editor,newIndex);
-	}
-	
+  @Override
+  public JungleTreeEditor getTreeEditor() {
+    TreeContext tc = repository.get();
+    DefaultTransactionManager txManager = new DefaultTransactionManager(writer, tc, repository, uuid);
+    TreeNode root = tc.getTreeNode();
+    TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> index = getIndex();
+    return new DefaultJungleTreeEditor(root, txManager, editor, index);
+  }
+
+  @Override
+  public IndexJungleTreeEditor getIndexTreeEditor() {
+    TreeContext tc = repository.get();
+    DefaultTransactionManager txManager = new DefaultTransactionManager(writer, tc, repository, uuid);
+    TreeNode root = tc.getTreeNode();
+    TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> newIndex = getIndex();
+    return new IndexJungleTreeEditor(root, txManager, editor, newIndex);
+  }
+
+  @Override
+  public JungleTreeEditor getLocalTreeEditor() {
+    return getTreeEditor();
+  }
+
+  @Override
+  public TreeNode getRootNode() {
+    TreeContext tc = repository.get();
+    ChangeSet cs = tc.getChangeSet();
+    return cs.getRoot();
+  }
 
-	@Override
-	public JungleTreeEditor getLocalTreeEditor()
-	{
-		return getTreeEditor();
-	}
-	
-	@Override
-	public TreeNode getRootNode()
-	{
-		TreeContext tc = repository.get();
-		ChangeSet cs = tc.getChangeSet();
-		return cs.getRoot();
-	}
+  @Override
+  public InterfaceTraverser getTraverser() {
+    AtomicReservableReference<TreeContext>.Reservation reservation = repository.getReservation();
+    IndexManager indexManager = new IndexManager(reservation);
+    TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> index = getIndex();
+    if (index != null)
+      return new InterfaceTraverser(getRootNode(), index, indexManager);
+    return new InterfaceTraverser(getRootNode(), indexManager);
+  }
+
+  @Override
+  public TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> getIndex() {
+    TreeContext tc = repository.get();
+    ChangeSet cs = tc.getChangeSet();
+    return cs.getIndex();
+  }
+
+  @Override
+  public Iterable<TreeOperation> getLog() {
+    TreeContext tc = repository.get();
+    ChangeSet cs = tc.getChangeSet();
+    return cs.getOperations();
+  }
 
-	@Override
-	public InterfaceTraverser getTraverser() {
-		AtomicReservableReference<TreeContext>.Reservation reservation = repository.getReservation();
-		IndexManager indexManager = new IndexManager(reservation);
-		TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> index = getIndex();
-		if (index != null)
-			return new InterfaceTraverser(getRootNode(), index, indexManager);
-		return new InterfaceTraverser(getRootNode(),indexManager);
-	}
-	
-	@Override
-	public TreeMap<String, TreeMap<String, List<Pair<TreeNode, NodePath>>>> getIndex() {
-		TreeContext tc = repository.get();
-		ChangeSet cs = tc.getChangeSet();
-		return cs.getIndex();
-	}
-	
-	@Override
-	public Iterable<TreeOperation> getLog() {
-		TreeContext tc = repository.get();
-		ChangeSet cs = tc.getChangeSet();
-		return cs.getOperations();
-	}
-	
+  @Override
+  public long revision() {
+    TreeContext tc = repository.get();
+    ChangeSet cs = tc.getChangeSet();
+    return cs.revision();
+  }
+
+  @Override
+  public Either<Error, JungleTree> getOldTree(long revision) {
+    TreeContext tc = repository.get();
+    ChangeSet cs = tc.getChangeSet();
+    
+    for (;cs.revision() != revision;) {
+      cs = cs.prev();
+      if (cs == null)
+        return DefaultEither.newA(GetOldTreeError.OLD_TREE_NOT_FOUND);
+    }
+    
+    TreeNode root = cs.getRoot();
+    
+    TreeContext oldTc = new DefaultTreeContext(root, cs);
+    String oldTreeUuid = uuid + revision;
+    JungleTree oldTree = new DefaultJungleTree(oldTc,oldTreeUuid,writer,editor);
+    return DefaultEither.newB(oldTree);
+  }
+  
+
 }