diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/CommitId.java b/platform/vcs-log/api/src/com/intellij/vcs/log/CommitId.java
similarity index 100%
rename from platform/vcs-log/impl/src/com/intellij/vcs/log/CommitId.java
rename to platform/vcs-log/api/src/com/intellij/vcs/log/CommitId.java
diff --git a/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLog.java b/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLog.java
index 5718742f492f..f2f25061fd8f 100644
--- a/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLog.java
+++ b/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLog.java
@@ -32,7 +32,7 @@ public interface VcsLog {
    * Returns commits currently selected in the log.
    */
   @NotNull
-  List<Hash> getSelectedCommits();
+  List<CommitId> getSelectedCommits();
 
   /**
    * Returns details of the selected commits if all of them have been loaded.
diff --git a/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLogDataProvider.java b/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLogDataProvider.java
index 55caadd9a270..597afd40082b 100644
--- a/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLogDataProvider.java
+++ b/platform/vcs-log/api/src/com/intellij/vcs/log/VcsLogDataProvider.java
@@ -23,7 +23,7 @@ import org.jetbrains.annotations.NotNull;
 public interface VcsLogDataProvider {
 
   @NotNull
-  Hash getHash(int commitIndex);
+  CommitId getCommitId(int commitIndex);
 
   int getCommitIndex(@NotNull Hash hash, @NotNull VirtualFile root);
 
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/VcsLogHashMap.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/VcsLogHashMap.java
index 0c337b545250..8e65ee917e7c 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/VcsLogHashMap.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/VcsLogHashMap.java
@@ -28,7 +28,7 @@ public interface VcsLogHashMap {
   int getCommitIndex(@NotNull Hash hash, @NotNull VirtualFile root);
 
   @NotNull
-  Hash getHash(int commitIndex);
+  CommitId getCommitId(int commitIndex);
 
   /**
    * Iterates over known commid id to find the first one which satisfies given condition.
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/AbstractDataGetter.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/AbstractDataGetter.java
index a4ce8cce6ed9..874fec2aba06 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/AbstractDataGetter.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/AbstractDataGetter.java
@@ -88,7 +88,7 @@ abstract class AbstractDataGetter<T extends VcsShortCommitDetails> implements Di
   @Nullable
   public T getCommitData(int row, @NotNull GraphTableModel tableModel) {
     assert EventQueue.isDispatchThread();
-    Integer hash = tableModel.getCommitIdAtRow(row);
+    Integer hash = tableModel.getIdAtRow(row);
     T details = getFromCache(hash);
     if (details != null) {
       return details;
@@ -140,7 +140,7 @@ abstract class AbstractDataGetter<T extends VcsShortCommitDetails> implements Di
 
             @Override
             public Hash compute() {
-              return myHashMap.getHash(commitId);
+              return myHashMap.getCommitId(commitId).getHash();
             }
           }, taskNumber, root));
         }
@@ -158,7 +158,7 @@ abstract class AbstractDataGetter<T extends VcsShortCommitDetails> implements Di
                                                                  int below) {
     MultiMap<VirtualFile, Integer> commits = MultiMap.create();
     for (int row = Math.max(0, selectedRow - above); row < selectedRow + below && row < model.getRowCount(); row++) {
-      Integer hash = model.getCommitIdAtRow(row);
+      Integer hash = model.getIdAtRow(row);
       VirtualFile root = model.getRoot(row);
       commits.putValue(root, hash);
     }
@@ -170,7 +170,7 @@ abstract class AbstractDataGetter<T extends VcsShortCommitDetails> implements Di
       List<String> hashStrings = ContainerUtil.map(entry.getValue(), new Function<Integer, String>() {
         @Override
         public String fun(Integer commitId) {
-          return myHashMap.getHash(commitId).asString();
+          return myHashMap.getCommitId(commitId).getHash().asString();
         }
       });
       List<? extends T> details = readDetails(myLogProviders.get(entry.getKey()), entry.getKey(), hashStrings);
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/DataPack.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/DataPack.java
index 4aebe3f5750d..d230f3bda0b5 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/DataPack.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/DataPack.java
@@ -55,7 +55,7 @@ public class DataPack {
       @NotNull
       @Override
       public Hash fun(Integer commitIndex) {
-        return hashMap.getHash(commitIndex);
+        return hashMap.getCommitId(commitIndex).getHash();
       }
     };
     GraphColorManagerImpl colorManager = new GraphColorManagerImpl(refsModel, hashGetter, getRefManagerMap(providers));
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogDataHolder.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogDataHolder.java
index 669db7dc3935..62014f0a99ae 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogDataHolder.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogDataHolder.java
@@ -126,8 +126,8 @@ public class VcsLogDataHolder implements Disposable, VcsLogDataProvider {
 
   @Override
   @NotNull
-  public Hash getHash(int commitIndex) {
-    return myHashMap.getHash(commitIndex);
+  public CommitId getCommitId(int commitIndex) {
+    return myHashMap.getCommitId(commitIndex);
   }
 
   @Override
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogHashMapImpl.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogHashMapImpl.java
index 5fc13c493b89..bb3f4dcbcd36 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogHashMapImpl.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/data/VcsLogHashMapImpl.java
@@ -61,7 +61,7 @@ public class VcsLogHashMapImpl implements Disposable, VcsLogHashMap {
 
     @NotNull
     @Override
-    public Hash getHash(int commitIndex) {
+    public CommitId getCommitId(int commitIndex) {
       throw new UnsupportedOperationException("Illegal access to empty hash map by index " + commitIndex);
     }
 
@@ -125,7 +125,7 @@ public class VcsLogHashMapImpl implements Disposable, VcsLogHashMap {
   }
 
   @Nullable
-  private CommitId doGetHash(int index) throws IOException {
+  private CommitId doGetCommitId(int index) throws IOException {
     return myPersistentEnumerator.valueOf(index);
   }
 
@@ -145,13 +145,13 @@ public class VcsLogHashMapImpl implements Disposable, VcsLogHashMap {
 
   @Override
   @NotNull
-  public Hash getHash(int commitIndex) {
+  public CommitId getCommitId(int commitIndex) {
     try {
-      CommitId commitId = doGetHash(commitIndex);
+      CommitId commitId = doGetCommitId(commitIndex);
       if (commitId == null) {
         throw new RuntimeException("Unknown commit index: " + commitIndex); // TODO this shouldn't happen => need to recreate the map
       }
-      return commitId.getHash();
+      return commitId;
     }
     catch (IOException e) {
       throw new RuntimeException(e); // TODO map is corrupted => need to recreate it
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/impl/VcsLogImpl.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/impl/VcsLogImpl.java
index 9efa903e864e..492f3843d5fb 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/impl/VcsLogImpl.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/impl/VcsLogImpl.java
@@ -45,16 +45,16 @@ public class VcsLogImpl implements VcsLog {
 
   @Override
   @NotNull
-  public List<Hash> getSelectedCommits() {
-    List<Hash> hashes = ContainerUtil.newArrayList();
+  public List<CommitId> getSelectedCommits() {
+    List<CommitId> commitIds = ContainerUtil.newArrayList();
     JBTable table = myUi.getTable();
     for (int row : table.getSelectedRows()) {
-      Hash hash = ((GraphTableModel)table.getModel()).getHashAtRow(row);
-      if (hash != null) {
-        hashes.add(hash);
+      CommitId commitId = ((GraphTableModel)table.getModel()).getCommitIdAtRow(row);
+      if (commitId != null) {
+        commitIds.add(commitId);
       }
     }
-    return hashes;
+    return commitIds;
   }
 
   @NotNull
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/frame/MainFrame.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/frame/MainFrame.java
index 5657db8e12eb..66b2fd0bee33 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/frame/MainFrame.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/frame/MainFrame.java
@@ -326,11 +326,11 @@ public class MainFrame extends JPanel implements TypeSafeDataProvider {
         }));
     }
     else if (VcsDataKeys.VCS_REVISION_NUMBERS == key) {
-      List<Hash> hashes = myUI.getVcsLog().getSelectedCommits();
-      sink.put(key, ArrayUtil.toObjectArray(ContainerUtil.map(hashes, new Function<Hash, VcsRevisionNumber>() {
+      List<CommitId> hashes = myUI.getVcsLog().getSelectedCommits();
+      sink.put(key, ArrayUtil.toObjectArray(ContainerUtil.map(hashes, new Function<CommitId, VcsRevisionNumber>() {
         @Override
-        public VcsRevisionNumber fun(Hash hash) {
-          return convertToRevisionNumber(hash);
+        public VcsRevisionNumber fun(CommitId commitId) {
+          return convertToRevisionNumber(commitId.getHash());
         }
       }), VcsRevisionNumber.class));
     }
diff --git a/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/tables/GraphTableModel.java b/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/tables/GraphTableModel.java
index b374beef1c59..6f87dd1ef81d 100644
--- a/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/tables/GraphTableModel.java
+++ b/platform/vcs-log/impl/src/com/intellij/vcs/log/ui/tables/GraphTableModel.java
@@ -61,7 +61,7 @@ public class GraphTableModel extends AbstractTableModel {
     int head = myDataPack.getVisibleGraph().getRowInfo(rowIndex).getOneOfHeads();
     Collection<VcsRef> refs = myDataPack.getRefsModel().refsToCommit(head);
     if (refs.isEmpty()) {
-      LOG.error("No references pointing to head " + myDataHolder.getHash(head) + " identified for commit at row " + rowIndex,
+      LOG.error("No references pointing to head " + myDataHolder.getCommitId(head) + " identified for commit at row " + rowIndex,
                 new Attachment("details.txt", getErrorDetails()));
       // take the first root: it is the right choice in one-repo case, though it will likely fail in multi-repo case
       return myDataPack.getLogProviders().keySet().iterator().next();
@@ -76,7 +76,7 @@ public class GraphTableModel extends AbstractTableModel {
     List<GraphCommit<Integer>> commits = myDataPack.getPermanentGraph().getAllCommits();
     for (int i = 0; i < 100 && i < commits.size(); i++) {
       GraphCommit<Integer> commit = commits.get(i);
-      sb.append(String.format("%s -> %s\n", myDataHolder.getHash(commit.getId()).toShortString(), getParents(commit)));
+      sb.append(String.format("%s -> %s\n", myDataHolder.getCommitId(commit.getId()).getHash().toShortString(), getParents(commit)));
     }
     sb.append("\nALL REFS:\n");
     printRefs(sb, myDataPack.getRefsModel().getAllRefsByRoot());
@@ -88,7 +88,7 @@ public class GraphTableModel extends AbstractTableModel {
     return StringUtil.join(commit.getParents(), new Function<Integer, String>() {
       @Override
       public String fun(Integer integer) {
-        return myDataHolder.getHash(integer).toShortString();
+        return myDataHolder.getCommitId(integer).getHash().toShortString();
       }
     }, ", ");
   }
@@ -117,13 +117,13 @@ public class GraphTableModel extends AbstractTableModel {
   }
 
   @NotNull
-  public Integer getCommitIdAtRow(int row) {
+  public Integer getIdAtRow(int row) {
     return myDataPack.getVisibleGraph().getRowInfo(row).getCommit();
   }
 
   @Nullable
-  public Hash getHashAtRow(int row) {
-    return myDataHolder.getHash(getCommitIdAtRow(row));
+  public CommitId getCommitIdAtRow(int row) {
+    return myDataHolder.getCommitId(getIdAtRow(row));
   }
 
   public int getRowOfCommit(@NotNull final Hash hash, @NotNull VirtualFile root) {
diff --git a/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VcsLogRefresherTest.java b/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VcsLogRefresherTest.java
index acf26d51c312..2c50ebdee6f6 100644
--- a/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VcsLogRefresherTest.java
+++ b/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VcsLogRefresherTest.java
@@ -236,7 +236,7 @@ public class VcsLogRefresherTest extends VcsLogPlatformTest {
           @NotNull
           @Override
           public Hash fun(Integer integer) {
-            return myDataHolder.getHash(integer);
+            return myDataHolder.getCommitId(integer).getHash();
           }
         };
         return new TimedVcsCommitImpl(convertor.fun(commit.getId()), ContainerUtil.map(commit.getParents(), convertor),
diff --git a/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VisiblePackBuilderTest.kt b/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VisiblePackBuilderTest.kt
index e844da1f80de..592fca3eb5a9 100644
--- a/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VisiblePackBuilderTest.kt
+++ b/platform/vcs-log/impl/test/com/intellij/vcs/log/data/VisiblePackBuilderTest.kt
@@ -116,7 +116,7 @@ class VisiblePackBuilderTest {
     assertDoesNotContain(visibleGraph, 1)
   }
 
-  private fun GraphCommit<Int>.toVcsCommit(map: VcsLogHashMap) = TimedVcsCommitImpl(map.getHash(this.getId()), map.getHashes(this.getParents()), 1)
+  private fun GraphCommit<Int>.toVcsCommit(map: VcsLogHashMap) = TimedVcsCommitImpl(map.getCommitId(this.getId()).hash, map.getHashes(this.getParents()), 1)
 
   fun assertDoesNotContain(graph: VisibleGraph<Int>, id: Int) {
     assertTrue(null == (1..graph.getVisibleCommitCount()).firstOrNull { graph.getRowInfo(it - 1).getCommit() == id })
@@ -130,16 +130,16 @@ class VisiblePackBuilderTest {
                     val data: HashMap<GraphCommit<Int>, Data>) {
     val root: VirtualFile = MockVirtualFile("root")
     val providers: Map<VirtualFile, TestVcsLogProvider> = mapOf(root to TestVcsLogProvider(root))
-    val hashMap = generateHashMap(commits.maxBy { it.getId() }!!.getId())
+    val hashMap = generateHashMap(commits.maxBy { it.getId() }!!.getId(), root)
 
     fun build(filters: VcsLogFilterCollection): VisiblePack {
       val refs = refs.mapTo(HashSet<VcsRef>(), {
-        VcsRefImpl(hashMap.getHash(it.commit), it.name, BRANCH_TYPE, root)
+        VcsRefImpl(hashMap.getCommitId(it.commit).hash, it.name, BRANCH_TYPE, root)
       })
 
       val dataPack = DataPack.build(commits, mapOf(root to refs), providers, hashMap, true)
       val detailsCache = data.entries.map {
-        val hash = hashMap.getHash(it.key.getId())
+        val hash = hashMap.getCommitId(it.key.getId()).hash
         val metadata = if (it.value.user == null)
           null
         else VcsCommitMetadataImpl(hash, hashMap.getHashes(it.key.getParents()), 1L, root, it.value.subject,
@@ -161,17 +161,17 @@ class VisiblePackBuilderTest {
       return builder.build(dataPack, PermanentGraph.SortType.Normal, filters, CommitCountStage.INITIAL).first
     }
 
-    fun generateHashMap(num: Int): VcsLogHashMap {
+    fun generateHashMap(num: Int, root: VirtualFile): VcsLogHashMap {
       val map = HashMap<Hash, Int>()
       for (i in 1..num) {
         map.put(HashImpl.build(i.toString()), i)
       }
-      return ConstantVcsLogHashMap(map)
+      return ConstantVcsLogHashMap(map, root)
     }
 
   }
 
-  fun VcsLogHashMap.getHashes(ids: List<Int>) = ids.map { getHash(it) }
+  fun VcsLogHashMap.getHashes(ids: List<Int>) = ids.map { getCommitId(it).hash }
 
   fun noFilters(): VcsLogFilterCollection = VcsLogFilterCollectionImpl(null, null, null, null, null, null, null)
 
@@ -225,12 +225,12 @@ class VisiblePackBuilderTest {
     fun done() = Graph(commits, refs, data)
   }
 
-  class ConstantVcsLogHashMap(val map: Map<Hash, Int>) : VcsLogHashMap {
-    val reverseMap = map.entries.map { Pair(it.value, it.key) }.toMap()
+  class ConstantVcsLogHashMap(val map: Map<Hash, Int>, val root: VirtualFile) : VcsLogHashMap {
+    val reverseMap = map.entrySet().map { Pair(it.value, it.key) }.toMap()
 
     override fun getCommitIndex(hash: Hash, root: VirtualFile) = map.get(hash)!!
 
-    override fun getHash(commitIndex: Int) = reverseMap.get(commitIndex)!!
+    override fun getCommitId(commitIndex: Int) = CommitId(reverseMap.get(commitIndex)!!, root)
 
     override fun findCommitId(condition: Condition<CommitId>): CommitId? = throw UnsupportedOperationException()
   }