Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/IndexWrapper.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/IndexWrapper.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/IndexWrapper.java	(date 1356004325000)
@@ -22,6 +22,8 @@
 import java.util.Iterator;
 import java.util.Set;
 
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.api.MicroKernelException;
 import org.apache.jackrabbit.mk.json.JsopReader;
@@ -113,6 +115,12 @@
         branchRevisions.remove(branchRevisionId);
         indexer.updateUntil(headRevision);
         return mk.getHeadRevision();
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 
     @Override
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/simple/SimpleKernelImpl.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/simple/SimpleKernelImpl.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/simple/SimpleKernelImpl.java	(date 1356004325000)
@@ -16,6 +16,13 @@
  */
 package org.apache.jackrabbit.oak.plugins.index.old.mk.simple;
 
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Collections;
+
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.api.MicroKernelException;
 import org.apache.jackrabbit.mk.blobs.AbstractBlobStore;
@@ -32,11 +39,6 @@
 import org.apache.jackrabbit.oak.plugins.index.old.mk.ExceptionFactory;
 import org.apache.jackrabbit.oak.plugins.index.old.mk.wrapper.MicroKernelWrapperBase;
 
-import java.io.IOException;
-import java.io.InputStream;
-import java.util.ArrayList;
-import java.util.Collections;
-
 /*
 
 Node structure:
@@ -610,6 +612,12 @@
     @Override
     public String merge(String branchRevisionId, String message) throws MicroKernelException {
         // TODO OAK-45 support
+        throw new UnsupportedOperationException();
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
         throw new UnsupportedOperationException();
     }
 }
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/BranchMergeMicroKernel.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/BranchMergeMicroKernel.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/BranchMergeMicroKernel.java	(date 1356004325000)
@@ -18,6 +18,9 @@
 
 import java.io.InputStream;
 import java.util.HashSet;
+
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.api.MicroKernelException;
 
@@ -184,6 +187,12 @@
         busyBranch = null;
         trunkHeadRevision = null;
         return getHeadRevision();
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 
     @Override
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/LogWrapper.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/LogWrapper.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/LogWrapper.java	(date 1356004325000)
@@ -19,6 +19,8 @@
 import java.io.InputStream;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.json.JsopBuilder;
 import org.apache.jackrabbit.oak.plugins.index.old.mk.ExceptionFactory;
@@ -225,6 +227,12 @@
             logException(e);
             throw convert(e);
         }
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 
     private void logMethod(String methodName, Object... args) {
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/MicroKernelWrapperBase.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/MicroKernelWrapperBase.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/MicroKernelWrapperBase.java	(date 1356004325000)
@@ -17,6 +17,9 @@
 package org.apache.jackrabbit.oak.plugins.index.old.mk.wrapper;
 
 import java.io.InputStream;
+
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.api.MicroKernelException;
 import org.apache.jackrabbit.mk.json.JsopReader;
@@ -148,6 +151,12 @@
         @Override
         public String merge(String branchRevisionId, String message) {
             return wrapped.merge(branchRevisionId, message);
+        }
+
+        @Nonnull
+        @Override
+        public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+            throw new UnsupportedOperationException();
         }
 
         @Override
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/SecurityWrapper.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/SecurityWrapper.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/SecurityWrapper.java	(date 1356004325000)
@@ -16,6 +16,10 @@
  */
 package org.apache.jackrabbit.oak.plugins.index.old.mk.wrapper;
 
+import java.io.InputStream;
+
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.json.JsopReader;
 import org.apache.jackrabbit.mk.json.JsopStream;
@@ -27,8 +31,6 @@
 import org.apache.jackrabbit.oak.plugins.index.old.mk.simple.NodeImpl;
 import org.apache.jackrabbit.oak.plugins.index.old.mk.simple.NodeMap;
 
-import java.io.InputStream;
-
 /**
  * A microkernel prototype implementation that filters nodes based on simple
  * access rights. Each user has a password, and (optionally) a list of rights,
@@ -358,6 +360,12 @@
     public String merge(String branchRevisionId, String message) {
         // TODO OAK-45 support
         return mk.merge(branchRevisionId, message);
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 
     private NodeImpl filterAccess(String path, NodeImpl n) {
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/TimingWrapper.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/TimingWrapper.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/TimingWrapper.java	(date 1356004325000)
@@ -22,6 +22,8 @@
 import java.util.Map.Entry;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.json.JsopBuilder;
 import org.apache.jackrabbit.oak.plugins.index.old.mk.ExceptionFactory;
@@ -288,6 +290,12 @@
             logException(e);
             throw convert(e);
         }
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 
     private void logMethod(String methodName, Object... args) {
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/VirtualRepositoryWrapper.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/VirtualRepositoryWrapper.java	(date 1357827292000)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/index/old/mk/wrapper/VirtualRepositoryWrapper.java	(date 1356004325000)
@@ -21,6 +21,8 @@
 import java.util.TreeMap;
 import java.util.Map.Entry;
 
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.api.MicroKernelException;
 import org.apache.jackrabbit.mk.json.JsopBuilder;
@@ -343,6 +345,12 @@
     public String merge(String branchRevisionId, String message) {
         // TODO OAK-45 support
         return mk.merge(branchRevisionId, message);
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 }
 
Index: oak-mk-api/src/main/java/org/apache/jackrabbit/mk/api/MicroKernel.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mk-api/src/main/java/org/apache/jackrabbit/mk/api/MicroKernel.java	(date 1357827292000)
+++ oak-mk-api/src/main/java/org/apache/jackrabbit/mk/api/MicroKernel.java	(date 1356004325000)
@@ -18,6 +18,8 @@
 
 import java.io.InputStream;
 
+import javax.annotation.Nonnull;
+
 /**
  * The MicroKernel <b>Design Goals and Principles</b>:
  * <ul>
@@ -480,6 +482,27 @@
      */
     String /* revisionId */ merge(String branchRevisionId, String message)
             throws MicroKernelException;
+
+    /**
+     * Rebases the specified <i>private</i> branch revision on top of specified new base
+     * revision.
+     * <p/>
+     * A {@code MicroKernelException} is thrown if {@code branchRevisionId} doesn't
+     * exist, if it's not a branch revision, if {@code newBaseRevisionId} doesn't exist,
+     * if it's a branch revision, if the rebase fails because of conflicting changes or
+     * if another error occurs.
+     *
+     * @param branchRevisionId id of private branch revision
+     * @param newBaseRevisionId id of new base revision
+     * @return id of the rebased branch revision
+     * @throws MicroKernelException if {@code branchRevisionId} doesn't exist,
+     *                              if it's not a branch revision, if {@code newBaseRevisionId}
+     *                              doesn't exist, if it's a branch revision,
+     *                              if the rebase fails because of conflicting changes or
+     *                              if another error occurs.
+     */
+    @Nonnull
+    String /*revisionId */ rebase(@Nonnull String branchRevisionId, String newBaseRevisionId);
 
     //--------------------------------------------------< BLOB READ/WRITE ops >
 
Index: oak-mk-remote/src/main/java/org/apache/jackrabbit/mk/client/Client.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mk-remote/src/main/java/org/apache/jackrabbit/mk/client/Client.java	(date 1357827292000)
+++ oak-mk-remote/src/main/java/org/apache/jackrabbit/mk/client/Client.java	(date 1356004325000)
@@ -23,6 +23,7 @@
 import java.net.URISyntaxException;
 import java.util.concurrent.atomic.AtomicBoolean;
 
+import javax.annotation.Nonnull;
 import javax.net.SocketFactory;
 
 import org.apache.jackrabbit.mk.api.MicroKernel;
@@ -297,6 +298,12 @@
         } finally {
             IOUtils.closeQuietly(request);
         }
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 
     @Override
Index: oak-mk/src/main/java/org/apache/jackrabbit/mk/core/MicroKernelImpl.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mk/src/main/java/org/apache/jackrabbit/mk/core/MicroKernelImpl.java	(date 1357827292000)
+++ oak-mk/src/main/java/org/apache/jackrabbit/mk/core/MicroKernelImpl.java	(date 1356004325000)
@@ -16,15 +16,19 @@
  */
 package org.apache.jackrabbit.mk.core;
 
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.List;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.api.MicroKernelException;
+import org.apache.jackrabbit.mk.json.JsonObject;
 import org.apache.jackrabbit.mk.json.JsopBuilder;
 import org.apache.jackrabbit.mk.json.JsopReader;
 import org.apache.jackrabbit.mk.json.JsopTokenizer;
 import org.apache.jackrabbit.mk.model.Commit;
 import org.apache.jackrabbit.mk.model.CommitBuilder;
 import org.apache.jackrabbit.mk.model.Id;
-import org.apache.jackrabbit.mk.json.JsonObject;
 import org.apache.jackrabbit.mk.model.StoredCommit;
 import org.apache.jackrabbit.mk.model.tree.ChildNode;
 import org.apache.jackrabbit.mk.model.tree.DiffBuilder;
@@ -38,10 +42,6 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.InputStream;
-import java.util.ArrayList;
-import java.util.List;
-
 /**
  *
  */
@@ -124,6 +124,15 @@
         }
     }
 
+    private Id getBaseRevisionId(Id branchId) throws MicroKernelException {
+        try {
+            return rep.getBaseRevision(branchId);
+        }
+        catch (Exception e) {
+            throw new MicroKernelException(e);
+        }
+    }
+
     public String getRevisionHistory(long since, int maxEntries, String path) throws MicroKernelException {
         if (rep == null) {
             throw new IllegalStateException("this instance has already been disposed");
@@ -521,6 +530,28 @@
             return cb.doCommit(true).toString();
         } catch (Exception e) {
             throw new MicroKernelException(e);
+        }
+    }
+
+    @Override
+    public String rebase(String branchRevisionId, String newBaseRevisionId) {
+        Id branchId = Id.fromString(branchRevisionId);
+        Id baseId = getBaseRevisionId(branchId);
+        Id newBaseId = newBaseRevisionId == null ? getHeadRevisionId() : Id.fromString(newBaseRevisionId);
+
+        if (baseId.equals(newBaseId)) {
+            return branchRevisionId;
+        }
+        else {
+            Id newBranchId = Id.fromString(branch(newBaseRevisionId));
+            try {
+                CommitBuilder cb = rep.getCommitBuilder(newBranchId,
+                        "rebasing " + branchRevisionId + " onto " + newBaseRevisionId);
+                return cb.rebase(baseId, branchId).toString();
+            }
+            catch (Exception e) {
+                throw new MicroKernelException(e);
+            }
         }
     }
 
Index: oak-mk/src/main/java/org/apache/jackrabbit/mk/core/Repository.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mk/src/main/java/org/apache/jackrabbit/mk/core/Repository.java	(date 1357827292000)
+++ oak-mk/src/main/java/org/apache/jackrabbit/mk/core/Repository.java	(date 1356004325000)
@@ -16,6 +16,9 @@
  */
 package org.apache.jackrabbit.mk.core;
 
+import java.io.Closeable;
+import java.io.File;
+
 import org.apache.jackrabbit.mk.blobs.BlobStore;
 import org.apache.jackrabbit.mk.blobs.FileBlobStore;
 import org.apache.jackrabbit.mk.blobs.MemoryBlobStore;
@@ -31,9 +34,6 @@
 import org.apache.jackrabbit.mk.util.IOUtils;
 import org.apache.jackrabbit.oak.commons.PathUtils;
 
-import java.io.Closeable;
-import java.io.File;
-
 /**
  *
  */
@@ -142,6 +142,14 @@
             throw new IllegalStateException("not initialized");
         }
         return rs.getHeadCommitId();
+    }
+
+    public Id getBaseRevision(Id branchRevision) throws Exception {
+        if (!initialized) {
+            throw new IllegalStateException("not initialized");
+        }
+        StoredCommit commit = rs.getCommit(branchRevision);
+        return commit == null ? null : commit.getBranchRootId();
     }
 
     public StoredCommit getHeadCommit() throws Exception {
Index: oak-mk/src/main/java/org/apache/jackrabbit/mk/model/CommitBuilder.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mk/src/main/java/org/apache/jackrabbit/mk/model/CommitBuilder.java	(date 1357827292000)
+++ oak-mk/src/main/java/org/apache/jackrabbit/mk/model/CommitBuilder.java	(date 1356004325000)
@@ -16,6 +16,9 @@
  */
 package org.apache.jackrabbit.mk.model;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import org.apache.jackrabbit.mk.json.JsonObject;
 import org.apache.jackrabbit.mk.json.JsopBuilder;
 import org.apache.jackrabbit.mk.model.tree.DiffBuilder;
@@ -25,9 +28,6 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.ArrayList;
-import java.util.List;
-
 /**
  *
  */
@@ -186,6 +186,39 @@
             }
             newRevId = store.putCommit(token, newCommit);
         }
+
+        // reset instance
+        stagedTree.reset(newRevId);
+        changeLog.clear();
+
+        return newRevId;
+    }
+
+    public Id rebase(Id fromId, Id toId) throws Exception {
+        RevisionStore.PutToken token = store.createPutToken();
+
+        Id rebasedId = stagedTree.rebase(baseRevId, fromId, toId, token);
+
+        if (store.getCommit(toId).getRootNodeId().equals(rebasedId)) {
+            // the rebase didn't cause any changes,
+            // no need to create new commit object/update head revision
+            return toId;
+        }
+
+        StoredCommit baseCommit = store.getCommit(baseRevId);
+        MutableCommit newCommit = new MutableCommit();
+        newCommit.setParentId(baseRevId);
+        newCommit.setCommitTS(System.currentTimeMillis());
+        newCommit.setMsg(msg);
+        // dynamically build diff for rebased commit
+        String diff = new DiffBuilder(
+                store.getNodeState(store.getRootNode(toId)),
+                store.getNodeState(store.getNode(rebasedId)),
+                "/", -1, store, "").build();
+        newCommit.setChanges(diff);
+        newCommit.setRootNodeId(rebasedId);
+        newCommit.setBranchRootId(baseCommit.getBranchRootId());
+        Id newRevId = store.putCommit(token, newCommit);
 
         // reset instance
         stagedTree.reset(newRevId);
Index: oak-mk/src/main/java/org/apache/jackrabbit/mk/model/StagedNodeTree.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mk/src/main/java/org/apache/jackrabbit/mk/model/StagedNodeTree.java	(date 1357827292000)
+++ oak-mk/src/main/java/org/apache/jackrabbit/mk/model/StagedNodeTree.java	(date 1356004325000)
@@ -16,16 +16,20 @@
  */
 package org.apache.jackrabbit.mk.model;
 
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
 import org.apache.jackrabbit.mk.json.JsonObject;
 import org.apache.jackrabbit.mk.model.tree.NodeDelta;
+import org.apache.jackrabbit.mk.model.tree.NodeState;
+import org.apache.jackrabbit.mk.model.tree.PropertyState;
 import org.apache.jackrabbit.mk.store.NotFoundException;
 import org.apache.jackrabbit.mk.store.RevisionStore;
+import org.apache.jackrabbit.mk.store.RevisionStore.PutToken;
 import org.apache.jackrabbit.oak.commons.PathUtils;
 
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-
 /**
  * A {@code StagedNodeTree} provides methods to manipulate a specific revision
  * of the tree. The changes are recorded and can be persisted by calling
@@ -80,6 +84,21 @@
         return root != null ? root.persist(token) : null;
     }
 
+    public Id rebase(Id baseId, Id fromId, Id toId, PutToken token) throws Exception {
+        // reset staging area to new base revision
+        reset(baseId);
+
+        StoredNode baseRoot = store.getRootNode(baseId);
+        StoredNode fromRoot = store.getRootNode(fromId);
+        StoredNode toRoot = store.getRootNode(toId);
+
+        // recursively apply changes from 'fromRoot' to 'toRoot' to 'baseRoot'
+        rebaseNode(baseRoot, fromRoot, toRoot, "/");
+
+        // persist staged nodes
+        return persist(token);
+    }
+
     /**
      * Performs a three-way merge merging <i>our</i> tree (rooted at {@code ourRoot})
      * and <i>their</i> tree (identified by {@code newBaseRevisionId}),
@@ -360,6 +379,106 @@
             parent = node;
         }
         return node;
+    }
+
+    private void rebaseNode(StoredNode base, StoredNode from, StoredNode to, String path) throws Exception {
+        assert from != null;
+        assert to != null;
+        assert base != null;
+
+        NodeState baseState = store.getNodeState(base);
+        NodeDelta theirDelta = new NodeDelta(store, store.getNodeState(from), store.getNodeState(base));
+        NodeDelta delta = new NodeDelta(store, store.getNodeState(from), store.getNodeState(to));
+
+        // apply the changes
+        StagedNode stagedNode = getStagedNode(path, true);
+
+        for (Entry<String, String> added : delta.getAddedProperties().entrySet()) {
+            String name = added.getKey();
+            String value = added.getValue();
+
+            PropertyState p = baseState.getProperty(name);
+            if (p == null || value.equals(p.getEncodedValue())) {
+                stagedNode.getProperties().put(name, value);
+            }
+            else {
+                throw new Exception("Added property conflicts with existing property '" + name + "' at '" + path + '\'');
+            }
+        }
+
+        for (String removed : delta.getRemovedProperties().keySet()) {
+            if (baseState.getProperty(removed) != null) {
+                if (theirDelta.getAddedProperties().containsKey(removed)) {
+                    throw new Exception("Removed property conflicts with added property '" + removed + "' at '" + path + '\'');
+                }
+                if (theirDelta.getChangedProperties().containsKey(removed)) {
+                    throw new Exception("Removed property conflicts with changed property '" + removed + "' at '" + path + '\'');
+                }
+                stagedNode.getProperties().remove(removed);
+            }
+        }
+
+        for (Entry<String, String> changed : delta.getChangedProperties().entrySet()) {
+            String name = changed.getKey();
+            String value = changed.getValue();
+
+            PropertyState p = baseState.getProperty(name);
+            if (p == null) {
+                throw new Exception("Changed property conflicts with removed property '" + name + "' at '" + path + '\'');
+            }
+            else {
+                if (theirDelta.getAddedProperties().containsKey(name)) {
+                    throw new Exception("Changed property conflicts with added property '" + name + "' at '" + path + '\'');
+                }
+                String theirs = theirDelta.getChangedProperties().get(name);
+                if (theirs != null && !theirs.equals(value)) {
+                    throw new Exception("Changes property conflicts with changed property '" + name + "' at '" + path + '\'');
+                }
+                stagedNode.getProperties().put(name, value);
+            }
+        }
+
+        for (Entry<String, Id> added : delta.getAddedChildNodes().entrySet()) {
+            String name = added.getKey();
+            Id id = added.getValue();
+
+            NodeState n = baseState.getChildNode(name);
+            if (n == null) {
+                stagedNode.add(new ChildNodeEntry(name, id));
+            }
+            else {
+                throw new Exception("Added node conflicts with existing node '" + name + "' at '" + path + '\'');
+            }
+        }
+
+        for (String removed : delta.getRemovedChildNodes().keySet()) {
+            if (baseState.getChildNode(removed) != null) {
+                if (theirDelta.getAddedChildNodes().containsKey(removed)) {
+                    throw new Exception("Removed node conflicts with added node '" + removed + "' at '" + path + '\'');
+                }
+                if (theirDelta.getChangedChildNodes().containsKey(removed)) {
+                    throw new Exception("Removed node conflicts with changed node '" + removed + "' at '" + path + '\'');
+                }
+                stagedNode.remove(removed);
+            }
+        }
+
+        for (String changed : delta.getChangedChildNodes().keySet()) {
+            StoredNode changedBase = getChildNode(base, changed);
+            if (changedBase == null) {
+                throw new Exception("Changed node conflicts with removed node '" + changed + "' at '" + path + '\'');
+            }
+
+            StoredNode changedFrom = getChildNode(from, changed);
+            StoredNode changedTo = getChildNode(to, changed);
+            String changedPath = PathUtils.concat(path, changed);
+            rebaseNode(changedBase, changedFrom, changedTo, changedPath);
+        }
+    }
+
+    private StoredNode getChildNode(StoredNode parent, String name) throws Exception {
+        ChildNodeEntry cne = parent.getChildNodeEntry(name);
+        return cne == null ? null : store.getNode(cne.getId());
     }
 
     /**
Index: oak-mk/src/test/java/org/apache/jackrabbit/mk/MicroKernelImplTest.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mk/src/test/java/org/apache/jackrabbit/mk/MicroKernelImplTest.java	(date 1357827292000)
+++ oak-mk/src/test/java/org/apache/jackrabbit/mk/MicroKernelImplTest.java	(date 1356004325000)
@@ -19,6 +19,7 @@
 import java.io.File;
 
 import org.apache.commons.io.FileUtils;
+import org.apache.jackrabbit.mk.api.MicroKernelException;
 import org.apache.jackrabbit.mk.core.MicroKernelImpl;
 import org.junit.After;
 import org.junit.Before;
@@ -26,6 +27,10 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 public class MicroKernelImplTest {
     
@@ -63,4 +68,316 @@
         headRev = mk.commit("/", "+\"b\" : {}", mk.getHeadRevision(), null);
         assertFalse("Commit must not have same id as branch", headRev.equals(branchRev));
     }
+
+    @Test
+    public void rebaseWithoutChanges() {
+        String branch = mk.branch(null);
+        String rebased = mk.rebase(branch, null);
+        assertEquals(branch, rebased);
+    }
+
+    @Test
+    public void fastForwardRebase() {
+        String branch = mk.branch(null);
+        branch = mk.commit("", "+\"/a\":{}", branch, null);
+        String rebased = mk.rebase(branch, null);
+        assertEquals(branch, rebased);
+    }
+
+    @Test
+    public void rebaseEmptyBranch() {
+        String branch = mk.branch(null);
+        String trunkRev = mk.commit("", "+\"/a\":{}", null, null);
+        String rebased = mk.rebase(branch, null);
+
+        assertEquals("{\":childNodeCount\":1,\"a\":{}}", mk.getNodes("/", rebased, 0, 0, -1, null));
+        assertEquals("{\":childNodeCount\":1,\"a\":{}}", mk.getNodes("/", null, 0, 0, -1, null));
+        assertEquals(trunkRev, mk.getHeadRevision());
+        assertFalse((trunkRev.equals(rebased)));
+    }
+
+    @Test
+    public void rebaseAddNode() {
+        mk.commit("", "+\"/x\":{}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "+\"/x/b\":{}", branch, null);
+        String trunkRev = mk.commit("", "+\"/x/a\":{}", null, null);
+        String rebased = mk.rebase(branch, null);
+
+        assertEquals(1, mk.getChildNodeCount("/x", null));
+        assertNotNull(mk.getNodes("/x/a", null, 0, 0, -1, null));
+
+        assertEquals(1, mk.getChildNodeCount("/x", branch));
+        assertNotNull(mk.getNodes("/x/b", branch, 0, 0, -1, null));
+
+        assertEquals(2, mk.getChildNodeCount("/x", rebased));
+        assertNotNull(mk.getNodes("/x/a", rebased, 0, 0, -1, null));
+        assertNotNull(mk.getNodes("/x/b", rebased, 0, 0, -1, null));
+    }
+
+    @Test
+    public void rebaseRemoveNode() {
+        mk.commit("", "+\"/x\":{\"y\":{}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "-\"/x/y\"", branch, null);
+        String trunkRev = mk.commit("", "+\"/x/a\":{}", null, null);
+        String rebased = mk.rebase(branch, null);
+
+        assertEquals(2, mk.getChildNodeCount("/x", null));
+        assertNotNull(mk.getNodes("/x/a", null, 0, 0, -1, null));
+        assertNotNull(mk.getNodes("/x/y", null, 0, 0, -1, null));
+
+        assertEquals(0, mk.getChildNodeCount("/x", branch));
+
+        assertEquals(1, mk.getChildNodeCount("/x", rebased));
+        assertNotNull(mk.getNodes("/x/a", rebased, 0, 0, -1, null));
+    }
+
+    @Test
+    public void rebaseAddProperty() {
+        mk.commit("", "+\"/x\":{\"y\":{}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":42", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/q\":99", null, null);
+        String rebased = mk.rebase(branch, null);
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":42"));
+        assertFalse(branchNode.contains("\"q\":99"));
+
+        String rebasedNode = mk.getNodes("/x/y", rebased, 0, 0, -1, null);
+        assertTrue(rebasedNode.contains("\"p\":42"));
+        assertTrue(rebasedNode.contains("\"q\":99"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertFalse(trunkNode.contains("\"p\":42"));
+        assertTrue(trunkNode.contains("\"q\":99"));
+    }
+
+    @Test
+    public void rebaseRemoveProperty() {
+        mk.commit("", "+\"/x\":{\"y\":{\"p\":42}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":null", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/q\":99", null, null);
+        String rebased = mk.rebase(branch, null);
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertFalse(branchNode.contains("\"p\":42"));
+        assertFalse(branchNode.contains("\"q\":99"));
+
+        String rebasedNode = mk.getNodes("/x/y", rebased, 0, 0, -1, null);
+        assertFalse(rebasedNode.contains("\"p\":42"));
+        assertTrue(rebasedNode.contains("\"q\":99"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":42"));
+        assertTrue(trunkNode.contains("\"q\":99"));
+    }
+
+    @Test
+    public void rebaseChangeProperty() {
+        mk.commit("", "+\"/x\":{\"y\":{\"p\":42}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":41", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/q\":99", null, null);
+        String rebased = mk.rebase(branch, null);
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":41"));
+        assertFalse(branchNode.contains("\"q\":99"));
+
+        String rebasedNode = mk.getNodes("/x/y", rebased, 0, 0, -1, null);
+        assertTrue(rebasedNode.contains("\"p\":41"));
+        assertTrue(rebasedNode.contains("\"q\":99"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":42"));
+        assertTrue(trunkNode.contains("\"q\":99"));
+    }
+
+    @Test
+    public void rebaseChangePropertyWithSameValue() {
+        mk.commit("", "+\"/x\":{\"y\":{\"p\":42}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":99", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/p\":99", null, null);
+        String rebased = mk.rebase(branch, null);
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":99"));
+
+        String rebasedNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertTrue(rebasedNode.contains("\"p\":99"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":99"));
+    }
+
+    @Test
+    public void rebaseAddNodeConflict() {
+        mk.commit("", "+\"/x\":{}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "+\"/x/a\":{}", branch, null);
+        String trunkRev = mk.commit("", "+\"/x/a\":{}", null, null);
+        try {
+            mk.rebase(branch, null);
+            fail("Expected MicroKernelException for conflict at '/x/a'");
+        }
+        catch (MicroKernelException e) {
+            assertSame(Exception.class, e.getCause().getClass());
+        }
+
+        assertEquals(1, mk.getChildNodeCount("/x", null));
+        assertNotNull(mk.getNodes("/x/a", null, 0, 0, -1, null));
+
+        assertEquals(1, mk.getChildNodeCount("/x", branch));
+        assertNotNull(mk.getNodes("/x/a", branch, 0, 0, -1, null));
+    }
+
+    @Test
+    public void rebaseAddPropertyConflict() {
+        mk.commit("", "+\"/x\":{\"y\":{}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":42", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/p\":99", null, null);
+        try {
+            mk.rebase(branch, null);
+            fail("Expected MicroKernelException for conflict at '/x/y/p'");
+        }
+        catch (MicroKernelException e) {
+            assertSame(Exception.class, e.getCause().getClass());
+        }
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":42"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":99"));
+    }
+
+    @Test
+    public void rebaseRemovePropertyConflict() {
+        mk.commit("", "+\"/x\":{\"y\":{\"p\":42}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":99", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/p\":null", null, null);
+        try {
+            mk.rebase(branch, null);
+            fail("Expected MicroKernelException for conflict at '/x/y/p'");
+        }
+        catch (MicroKernelException e) {
+            assertSame(Exception.class, e.getCause().getClass());
+        }
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":99"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertFalse(trunkNode.contains("\"p\":42"));
+        assertFalse(trunkNode.contains("\"p\":99"));
+    }
+
+    @Test
+    public void rebaseRemoveChangedPropertyConflict() {
+        mk.commit("", "+\"/x\":{\"y\":{\"p\":42}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":null", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/p\":99", null, null);
+        try {
+            mk.rebase(branch, null);
+            fail("Expected MicroKernelException for conflict at '/x/y/p'");
+        }
+        catch (MicroKernelException e) {
+            assertSame(Exception.class, e.getCause().getClass());
+        }
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertFalse(branchNode.contains("\"p\":42"));
+        assertFalse(branchNode.contains("\"p\":99"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":99"));
+    }
+
+    @Test
+    public void rebaseChangedChangedPropertyConflict() {
+        mk.commit("", "+\"/x\":{\"y\":{\"p\":42}}", null, null);
+        String branch = mk.branch(null);
+        branch = mk.commit("", "^\"/x/y/p\":41", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/p\":99", null, null);
+        try {
+            mk.rebase(branch, null);
+            fail("Expected MicroKernelException for conflict at '/x/y/p'");
+        }
+        catch (MicroKernelException e) {
+            assertSame(Exception.class, e.getCause().getClass());
+        }
+
+        String branchNode = mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":41"));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":99"));
+    }
+
+    @Test
+    public void rebaseRemoveChangedNodeConflict() {
+        mk.commit("", "+\"/x\":{\"y\":{}}", null, null);
+        String branch = mk.branch(null);
+        mk.getNodes("/x/y", branch, 0, 0, -1, null);
+        branch = mk.commit("", "-\"/x/y\"", branch, null);
+        String trunkRev = mk.commit("", "^\"/x/y/p\":42", null, null);
+        try {
+            mk.rebase(branch, null);
+            fail("Expected MicroKernelException for conflict at '/x/y");
+        }
+        catch (MicroKernelException e) {
+            assertSame(Exception.class, e.getCause().getClass());
+        }
+
+        assertFalse(mk.nodeExists("/x/y", branch));
+
+        String trunkNode = mk.getNodes("/x/y", null, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":42"));
+    }
+
+    @Test
+    public void rebaseChangeRemovedNodeConflict() {
+        mk.commit("", "+\"/x\":{\"y\":{}}", null, null);
+        String branch = mk.branch(null);
+        String trunkRev = mk.commit("", "-\"/x\"", null, null);
+        branch = mk.commit("", "^\"/x/p\":42", branch, null);
+        try {
+            mk.rebase(branch, null);
+            fail("Expected MicroKernelException for conflict at '/x");
+        }
+        catch (MicroKernelException e) {
+            assertSame(Exception.class, e.getCause().getClass());
+        }
+
+        assertFalse(mk.nodeExists("/x", null));
+
+        String branchNode = mk.getNodes("/x", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":42"));
+    }
+
+    @Test
+    public void mergeRebased() {
+        mk.commit("", "+\"/x\":{\"y\":{}}", null, null);
+        String branch = mk.branch(null);
+        String trunkRev = mk.commit("", "^\"/x/p\":42", null, null);
+        branch = mk.commit("", "^\"/x/q\":43", branch, null);
+        branch = mk.rebase(branch, null);
+
+        String branchNode = mk.getNodes("/x", branch, 0, 0, -1, null);
+        assertTrue(branchNode.contains("\"p\":42"));
+        assertTrue(branchNode.contains("\"q\":43"));
+
+        mk.merge(branch, null);
+        String trunkNode = mk.getNodes("/x", branch, 0, 0, -1, null);
+        assertTrue(trunkNode.contains("\"p\":42"));
+        assertTrue(trunkNode.contains("\"q\":43"));
+    }
+
 }
Index: oak-mongomk/src/main/java/org/apache/jackrabbit/mongomk/impl/MongoMicroKernel.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-mongomk/src/main/java/org/apache/jackrabbit/mongomk/impl/MongoMicroKernel.java	(date 1357827292000)
+++ oak-mongomk/src/main/java/org/apache/jackrabbit/mongomk/impl/MongoMicroKernel.java	(date 1356004325000)
@@ -19,6 +19,8 @@
 import java.io.InputStream;
 import java.util.UUID;
 
+import javax.annotation.Nonnull;
+
 import org.apache.jackrabbit.mk.api.MicroKernel;
 import org.apache.jackrabbit.mk.api.MicroKernelException;
 import org.apache.jackrabbit.mk.blobs.BlobStore;
@@ -213,6 +215,12 @@
         } catch (Exception e) {
             throw new MicroKernelException(e);
         }
+    }
+
+    @Nonnull
+    @Override
+    public String rebase(@Nonnull String branchRevisionId, String newBaseRevisionId) {
+        throw new UnsupportedOperationException();
     }
 
     @Override
\ No newline at end of file