diff --git a/CHANGES.txt b/CHANGES.txt
index 9ab44f47624..42bb54f5861 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -52,6 +52,9 @@ New Features
  5. SOLR-793: Add 'commitWithin' argument to the update add command.  This behaves
     similar to the global autoCommit maxTime argument except that it is set for 
     each request.  (ryan)
+
+ 6. SOLR-670: Add support for rollbacks in UpdateHandler. This allows user to rollback all changes
+    since the last commit. (Noble Paul, koji via shalin)
     
 
 Optimizations
diff --git a/client/java/solrj/src/org/apache/solr/client/solrj/SolrServer.java b/client/java/solrj/src/org/apache/solr/client/solrj/SolrServer.java
index 74e6f91acff..b661d651977 100644
--- a/client/java/solrj/src/org/apache/solr/client/solrj/SolrServer.java
+++ b/client/java/solrj/src/org/apache/solr/client/solrj/SolrServer.java
@@ -92,7 +92,11 @@ public abstract class SolrServer implements Serializable
   public UpdateResponse optimize(boolean waitFlush, boolean waitSearcher, int maxSegments ) throws SolrServerException, IOException {
     return new UpdateRequest().setAction( UpdateRequest.ACTION.OPTIMIZE, waitFlush, waitSearcher, maxSegments ).process( this );
   }
-
+  
+  public UpdateResponse rollback() throws SolrServerException, IOException {
+    return new UpdateRequest().rollback().process( this );
+  }
+  
   public UpdateResponse deleteById(String id) throws SolrServerException, IOException {
     return new UpdateRequest().deleteById( id ).process( this );
   }
@@ -124,4 +128,4 @@ public abstract class SolrServer implements Serializable
     }
     return binder;
   }
-}
\ No newline at end of file
+}
diff --git a/client/java/solrj/src/org/apache/solr/client/solrj/request/UpdateRequest.java b/client/java/solrj/src/org/apache/solr/client/solrj/request/UpdateRequest.java
index 71432fb01d7..55599e102cd 100644
--- a/client/java/solrj/src/org/apache/solr/client/solrj/request/UpdateRequest.java
+++ b/client/java/solrj/src/org/apache/solr/client/solrj/request/UpdateRequest.java
@@ -140,6 +140,17 @@ public class UpdateRequest extends SolrRequest
     params.set( UpdateParams.WAIT_SEARCHER, waitSearcher+"" );
     return this;
   }
+
+  /**
+   * @since Solr 1.4
+   */
+  public UpdateRequest rollback() {
+    if (params == null)
+      params = new ModifiableSolrParams();
+
+    params.set( UpdateParams.ROLLBACK, "true" );
+    return this;
+  }
   
 
   public void setParam(String param, String value) {
diff --git a/src/java/org/apache/solr/common/params/UpdateParams.java b/src/java/org/apache/solr/common/params/UpdateParams.java
index 918767d6006..b354bcba601 100644
--- a/src/java/org/apache/solr/common/params/UpdateParams.java
+++ b/src/java/org/apache/solr/common/params/UpdateParams.java
@@ -37,8 +37,11 @@ public interface UpdateParams
   /** Commit everything after the command completes */
   public static String COMMIT = "commit";
   
-  /** Commit everything after the command completes */
+  /** Optimize the index and commit everything after the command completes */
   public static String OPTIMIZE = "optimize";
+  
+  /** Rollback update commands */
+  public static String ROLLBACK = "rollback";
 
   /** Select the update processor to use.  A RequestHandler may or may not respect this parameter */
   public static final String UPDATE_PROCESSOR = "update.processor";
diff --git a/src/java/org/apache/solr/handler/CSVRequestHandler.java b/src/java/org/apache/solr/handler/CSVRequestHandler.java
index 4eacca32cf9..c9c25b98851 100755
--- a/src/java/org/apache/solr/handler/CSVRequestHandler.java
+++ b/src/java/org/apache/solr/handler/CSVRequestHandler.java
@@ -59,8 +59,8 @@ public class CSVRequestHandler extends RequestHandlerBase {
 
       Iterable<ContentStream> streams = req.getContentStreams();
       if( streams == null ) {
-        if( !RequestHandlerUtils.handleCommit(processor, params, false) ) {
-          throw new SolrException( SolrException.ErrorCode.BAD_REQUEST, "missing content stream" );
+        if (!RequestHandlerUtils.handleCommit(processor, params, false) && !RequestHandlerUtils.handleRollback(processor, params, false)) {
+          throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "missing content stream");
         }
       }
       else {
@@ -77,6 +77,7 @@ public class CSVRequestHandler extends RequestHandlerBase {
 
         // Perhaps commit from the parameters
         RequestHandlerUtils.handleCommit( processor, params, false );
+        RequestHandlerUtils.handleRollback(processor,  params, false );
       }
     } finally {
       // finish the request
diff --git a/src/java/org/apache/solr/handler/RequestHandlerUtils.java b/src/java/org/apache/solr/handler/RequestHandlerUtils.java
index ebc83dbef1c..b5451852f58 100755
--- a/src/java/org/apache/solr/handler/RequestHandlerUtils.java
+++ b/src/java/org/apache/solr/handler/RequestHandlerUtils.java
@@ -26,6 +26,7 @@ import org.apache.solr.common.params.UpdateParams;
 import org.apache.solr.request.SolrQueryRequest;
 import org.apache.solr.request.SolrQueryResponse;
 import org.apache.solr.update.CommitUpdateCommand;
+import org.apache.solr.update.RollbackUpdateCommand;
 import org.apache.solr.update.processor.UpdateRequestProcessor;
 
 /**
@@ -106,4 +107,23 @@ public class RequestHandlerUtils
     }
     return false;
   }
+
+  /**
+   * @since Solr 1.4
+   */
+  public static boolean handleRollback( UpdateRequestProcessor processor, SolrParams params, boolean force ) throws IOException
+  {
+    if( params == null ) {
+      params = new MapSolrParams( new HashMap<String, String>() ); 
+    }
+    
+    boolean rollback = params.getBool( UpdateParams.ROLLBACK, false );
+    
+    if( rollback || force ) {
+      RollbackUpdateCommand cmd = new RollbackUpdateCommand();
+      processor.processRollback( cmd );
+      return true;
+    }
+    return false;
+  }
 }
diff --git a/src/java/org/apache/solr/handler/XmlUpdateRequestHandler.java b/src/java/org/apache/solr/handler/XmlUpdateRequestHandler.java
index 838852d2427..4967794172d 100644
--- a/src/java/org/apache/solr/handler/XmlUpdateRequestHandler.java
+++ b/src/java/org/apache/solr/handler/XmlUpdateRequestHandler.java
@@ -52,6 +52,7 @@ import org.apache.solr.request.SolrQueryResponse;
 import org.apache.solr.update.AddUpdateCommand;
 import org.apache.solr.update.CommitUpdateCommand;
 import org.apache.solr.update.DeleteUpdateCommand;
+import org.apache.solr.update.RollbackUpdateCommand;
 import org.apache.solr.update.processor.UpdateRequestProcessorChain;
 import org.apache.solr.update.processor.UpdateRequestProcessor;
 
@@ -69,6 +70,7 @@ public class XmlUpdateRequestHandler extends RequestHandlerBase
   public static final String DELETE = "delete";
   public static final String OPTIMIZE = "optimize";
   public static final String COMMIT = "commit";
+  public static final String ROLLBACK = "rollback";
   public static final String WAIT_SEARCHER = "waitSearcher";
   public static final String WAIT_FLUSH = "waitFlush";
   
@@ -113,8 +115,8 @@ public class XmlUpdateRequestHandler extends RequestHandlerBase
     UpdateRequestProcessor processor = processingChain.createProcessor(req, rsp);
     Iterable<ContentStream> streams = req.getContentStreams();
     if( streams == null ) {
-      if( !RequestHandlerUtils.handleCommit(processor, params, false) ) {
-        throw new SolrException( SolrException.ErrorCode.BAD_REQUEST, "missing content stream" );
+      if (!RequestHandlerUtils.handleCommit(processor, params, false) && !RequestHandlerUtils.handleRollback(processor, params, false)) {
+        throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "missing content stream");
       }
     }
     else {
@@ -138,6 +140,8 @@ public class XmlUpdateRequestHandler extends RequestHandlerBase
       
       // Perhaps commit from the parameters
       RequestHandlerUtils.handleCommit( processor, params, false );
+      // Perhaps rollback from the parameters
+      RequestHandlerUtils.handleRollback( processor, params, false );
     }
     
     // finish the request
@@ -236,6 +240,13 @@ public class XmlUpdateRequestHandler extends RequestHandlerBase
             }
             processor.processCommit( cmd );
           } // end commit
+          else if ( ROLLBACK.equals(currTag) ) {
+            log.trace("parsing " + currTag);
+
+            RollbackUpdateCommand cmd = new RollbackUpdateCommand();
+
+            processor.processRollback( cmd );
+          } // end rollback
           else if (DELETE.equals(currTag)) {
             log.trace("parsing delete");
             processDelete( processor, parser);
diff --git a/src/java/org/apache/solr/update/DirectUpdateHandler.java b/src/java/org/apache/solr/update/DirectUpdateHandler.java
index 87e4ad7a472..4eafc2516a2 100644
--- a/src/java/org/apache/solr/update/DirectUpdateHandler.java
+++ b/src/java/org/apache/solr/update/DirectUpdateHandler.java
@@ -188,7 +188,7 @@ public class DirectUpdateHandler extends UpdateHandler {
     if (!cmd.fromPending && !cmd.fromCommitted)
       throw new SolrException( SolrException.ErrorCode.BAD_REQUEST,"meaningless command: " + cmd);
     if (!cmd.fromPending || !cmd.fromCommitted)
-      throw new SolrException( SolrException.ErrorCode.BAD_REQUEST,"operation not supported" + cmd);
+      throw new SolrException( SolrException.ErrorCode.BAD_REQUEST,"operation not supported: " + cmd);
 
     Query q = QueryParsing.parseQuery(cmd.query, schema);
 
@@ -262,6 +262,13 @@ public class DirectUpdateHandler extends UpdateHandler {
     return;
   }
 
+  /**
+   * @since Solr 1.4
+   */
+  public void rollback(RollbackUpdateCommand cmd) throws IOException {
+    throw new SolrException( SolrException.ErrorCode.BAD_REQUEST,
+        "DirectUpdateHandler doesn't support rollback. Use DirectUpdateHandler2 instead.");
+  }
 
 
   ///////////////////////////////////////////////////////////////////
diff --git a/src/java/org/apache/solr/update/DirectUpdateHandler2.java b/src/java/org/apache/solr/update/DirectUpdateHandler2.java
index 1fcef351a98..e379d40027f 100644
--- a/src/java/org/apache/solr/update/DirectUpdateHandler2.java
+++ b/src/java/org/apache/solr/update/DirectUpdateHandler2.java
@@ -125,6 +125,7 @@ public class DirectUpdateHandler2 extends UpdateHandler {
   AtomicLong deleteByQueryCommandsCumulative= new AtomicLong();
   AtomicLong commitCommands= new AtomicLong();
   AtomicLong optimizeCommands= new AtomicLong();
+  AtomicLong rollbackCommands= new AtomicLong();
   AtomicLong numDocsPending= new AtomicLong();
   AtomicLong numErrors = new AtomicLong();
   AtomicLong numErrorsCumulative = new AtomicLong();
@@ -176,6 +177,12 @@ public class DirectUpdateHandler2 extends UpdateHandler {
     }
   }
 
+  // must only be called when iwCommit lock held
+  protected void rollbackWriter() throws IOException {
+    numDocsPending.set(0);
+    if (writer!=null) writer.rollback();
+  }
+
   public int addDoc(AddUpdateCommand cmd) throws IOException {
     addCommands.incrementAndGet();
     addCommandsCumulative.incrementAndGet();
@@ -370,6 +377,38 @@ public class DirectUpdateHandler2 extends UpdateHandler {
     }
   }
 
+  /**
+   * @since Solr 1.4
+   */
+  public void rollback(RollbackUpdateCommand cmd) throws IOException {
+
+    rollbackCommands.incrementAndGet();
+
+    boolean error=true;
+    iwCommit.lock();
+    try {
+      log.info("start "+cmd);
+
+      rollbackWriter();
+
+      //callPostRollbackCallbacks();
+
+      // reset commit tracking
+      tracker.didRollback();
+
+      log.info("end_rollback");
+
+      error=false;
+    }
+    finally {
+      iwCommit.unlock();
+      addCommands.set(0);
+      deleteByIdCommands.set(0);
+      deleteByQueryCommands.set(0);
+      numErrors.set(error ? 1 : 0);
+    }
+  }
+
 
   public void close() throws IOException {
     log.info("closing " + this);
@@ -467,6 +506,15 @@ public class DirectUpdateHandler2 extends UpdateHandler {
       docsSinceCommit = 0;
     }
 
+    /** Inform tracker that a rollback has occurred, cancel any pending commits */
+    public void didRollback() {
+      if( pending != null ) {
+        pending.cancel(false);
+        pending = null; // let it start another one
+      }
+      docsSinceCommit = 0;
+    }
+
     /** This is the worker part for the ScheduledFuture **/
     public synchronized void run() {
       long started = System.currentTimeMillis();
@@ -556,6 +604,7 @@ public class DirectUpdateHandler2 extends UpdateHandler {
     }
     lst.add("autocommits", tracker.autoCommitCount);
     lst.add("optimizes", optimizeCommands.get());
+    lst.add("rollbacks", rollbackCommands.get());
     lst.add("docsPending", numDocsPending.get());
     // pset.size() not synchronized, but it should be fine to access.
     // lst.add("deletesPending", pset.size());
diff --git a/src/java/org/apache/solr/update/RollbackUpdateCommand.java b/src/java/org/apache/solr/update/RollbackUpdateCommand.java
new file mode 100644
index 00000000000..68c2a35032c
--- /dev/null
+++ b/src/java/org/apache/solr/update/RollbackUpdateCommand.java
@@ -0,0 +1,30 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.solr.update;
+
+/**
+ * @version $Id$
+ * @since Solr 1.4
+ */
+public class RollbackUpdateCommand extends UpdateCommand {
+
+  public RollbackUpdateCommand() {
+    super("rollback");
+  }
+
+}
diff --git a/src/java/org/apache/solr/update/UpdateHandler.java b/src/java/org/apache/solr/update/UpdateHandler.java
index 620b8436dd4..15c9ee3dec7 100644
--- a/src/java/org/apache/solr/update/UpdateHandler.java
+++ b/src/java/org/apache/solr/update/UpdateHandler.java
@@ -156,6 +156,7 @@ public abstract class UpdateHandler implements SolrInfoMBean {
   public abstract void delete(DeleteUpdateCommand cmd) throws IOException;
   public abstract void deleteByQuery(DeleteUpdateCommand cmd) throws IOException;
   public abstract void commit(CommitUpdateCommand cmd) throws IOException;
+  public abstract void rollback(RollbackUpdateCommand cmd) throws IOException;
   public abstract void close() throws IOException;
 
 
diff --git a/src/java/org/apache/solr/update/processor/LogUpdateProcessorFactory.java b/src/java/org/apache/solr/update/processor/LogUpdateProcessorFactory.java
index fb7fdd4ab24..7ddd8ed33ec 100644
--- a/src/java/org/apache/solr/update/processor/LogUpdateProcessorFactory.java
+++ b/src/java/org/apache/solr/update/processor/LogUpdateProcessorFactory.java
@@ -29,6 +29,7 @@ import org.apache.solr.request.SolrQueryResponse;
 import org.apache.solr.update.AddUpdateCommand;
 import org.apache.solr.update.CommitUpdateCommand;
 import org.apache.solr.update.DeleteUpdateCommand;
+import org.apache.solr.update.RollbackUpdateCommand;
 
 /**
  * A logging processor.  This keeps track of all commands that have passed through
@@ -131,6 +132,16 @@ class LogUpdateProcessor extends UpdateRequestProcessor {
     toLog.add(cmd.optimize ? "optimize" : "commit", "");
   }
 
+  /**
+   * @since Solr 1.4
+   */
+  @Override
+  public void processRollback( RollbackUpdateCommand cmd ) throws IOException {
+    if (next != null) next.processRollback(cmd);
+    
+    toLog.add("rollback", "");
+  }
+
 
   @Override
   public void finish() throws IOException {
diff --git a/src/java/org/apache/solr/update/processor/RunUpdateProcessorFactory.java b/src/java/org/apache/solr/update/processor/RunUpdateProcessorFactory.java
index a5e2c6d0e1e..ed6c1c6e0a6 100644
--- a/src/java/org/apache/solr/update/processor/RunUpdateProcessorFactory.java
+++ b/src/java/org/apache/solr/update/processor/RunUpdateProcessorFactory.java
@@ -25,6 +25,7 @@ import org.apache.solr.update.AddUpdateCommand;
 import org.apache.solr.update.CommitUpdateCommand;
 import org.apache.solr.update.DeleteUpdateCommand;
 import org.apache.solr.update.DocumentBuilder;
+import org.apache.solr.update.RollbackUpdateCommand;
 import org.apache.solr.update.UpdateHandler;
 
 
@@ -77,6 +78,16 @@ class RunUpdateProcessor extends UpdateRequestProcessor
     updateHandler.commit(cmd);
     super.processCommit(cmd);
   }
+
+  /**
+   * @since Solr 1.4
+   */
+  @Override
+  public void processRollback(RollbackUpdateCommand cmd) throws IOException
+  {
+    updateHandler.rollback(cmd);
+    super.processRollback(cmd);
+  }
 }
 
 
diff --git a/src/java/org/apache/solr/update/processor/UpdateRequestProcessor.java b/src/java/org/apache/solr/update/processor/UpdateRequestProcessor.java
index 60edd8dcb80..0397645ad57 100644
--- a/src/java/org/apache/solr/update/processor/UpdateRequestProcessor.java
+++ b/src/java/org/apache/solr/update/processor/UpdateRequestProcessor.java
@@ -24,6 +24,7 @@ import org.slf4j.LoggerFactory;
 import org.apache.solr.update.AddUpdateCommand;
 import org.apache.solr.update.CommitUpdateCommand;
 import org.apache.solr.update.DeleteUpdateCommand;
+import org.apache.solr.update.RollbackUpdateCommand;
 
 
 /**
@@ -60,6 +61,14 @@ public abstract class UpdateRequestProcessor {
     if (next != null) next.processCommit(cmd);
   }
 
+  /**
+   * @since Solr 1.4
+   */
+  public void processRollback(RollbackUpdateCommand cmd) throws IOException
+  {
+    if (next != null) next.processRollback(cmd);
+  }
+
   public void finish() throws IOException {
     if (next != null) next.finish();    
   }
diff --git a/src/test/org/apache/solr/update/DirectUpdateHandlerTest.java b/src/test/org/apache/solr/update/DirectUpdateHandlerTest.java
index eeee6a797a0..16fe7a161e3 100644
--- a/src/test/org/apache/solr/update/DirectUpdateHandlerTest.java
+++ b/src/test/org/apache/solr/update/DirectUpdateHandlerTest.java
@@ -17,12 +17,19 @@
 
 package org.apache.solr.update;
 
+import java.util.HashMap;
+import java.util.Map;
+
 import org.apache.lucene.document.Document;
 import org.apache.lucene.document.Field;
 import org.apache.lucene.document.Field.Index;
 import org.apache.lucene.document.Field.Store;
 import org.apache.solr.common.SolrException;
+import org.apache.solr.common.params.CommonParams;
+import org.apache.solr.common.params.MapSolrParams;
 import org.apache.solr.core.SolrCore;
+import org.apache.solr.request.LocalSolrQueryRequest;
+import org.apache.solr.request.SolrQueryRequest;
 import org.apache.solr.util.AbstractSolrTestCase;
 
 /**
@@ -74,5 +81,183 @@ public class DirectUpdateHandlerTest extends AbstractSolrTestCase {
     }
     catch( SolrException ex ) { } // expected
   }
+
+  public void testUncommit() throws Exception {
+    addSimpleDoc("A");
+
+    // search - not committed - "A" should not be found.
+    Map<String,String> args = new HashMap<String, String>();
+    args.put( CommonParams.Q, "id:A" );
+    args.put( "indent", "true" );
+    SolrQueryRequest req = new LocalSolrQueryRequest( h.getCore(), new MapSolrParams( args) );
+    assertQ("\"A\" should not be found.", req
+            ,"//*[@numFound='0']"
+            );
+  }
+
+  public void testAddCommit() throws Exception {
+    addSimpleDoc("A");
+
+    // commit "A"
+    SolrCore core = h.getCore();
+    UpdateHandler updater = core.getUpdateHandler();
+    CommitUpdateCommand cmtCmd = new CommitUpdateCommand(false);
+    cmtCmd.waitSearcher = true;
+    updater.commit(cmtCmd);
+
+    // search - "A" should be found.
+    Map<String,String> args = new HashMap<String, String>();
+    args.put( CommonParams.Q, "id:A" );
+    args.put( "indent", "true" );
+    SolrQueryRequest req = new LocalSolrQueryRequest( core, new MapSolrParams( args) );
+    assertQ("\"A\" should be found.", req
+            ,"//*[@numFound='1']"
+            ,"//result/doc[1]/int[@name='id'][.='A']"
+            );
+  }
+
+  public void testDeleteCommit() throws Exception {
+    addSimpleDoc("A");
+    addSimpleDoc("B");
+
+    // commit "A", "B"
+    SolrCore core = h.getCore();
+    UpdateHandler updater = core.getUpdateHandler();
+    CommitUpdateCommand cmtCmd = new CommitUpdateCommand(false);
+    cmtCmd.waitSearcher = true;
+    updater.commit(cmtCmd);
+
+    // search - "A","B" should be found.
+    Map<String,String> args = new HashMap<String, String>();
+    args.put( CommonParams.Q, "id:A OR id:B" );
+    args.put( "indent", "true" );
+    SolrQueryRequest req = new LocalSolrQueryRequest( core, new MapSolrParams( args) );
+    assertQ("\"A\" and \"B\" should be found.", req
+            ,"//*[@numFound='2']"
+            ,"//result/doc[1]/int[@name='id'][.='A']"
+            ,"//result/doc[2]/int[@name='id'][.='B']"
+            );
+
+    // delete "B"
+    deleteSimpleDoc("B");
+
+    // search - "A","B" should be found.
+    assertQ("\"A\" and \"B\" should be found.", req
+            ,"//*[@numFound='2']"
+            ,"//result/doc[1]/int[@name='id'][.='A']"
+            ,"//result/doc[2]/int[@name='id'][.='B']"
+            );
+ 
+    // commit
+    updater.commit(cmtCmd);
+    
+    // search - "B" should not be found.
+    assertQ("\"B\" should not be found.", req
+        ,"//*[@numFound='1']"
+        ,"//result/doc[1]/int[@name='id'][.='A']"
+        );
+  }
+
+  public void testAddRollback() throws Exception {
+    addSimpleDoc("A");
+
+    // commit "A"
+    SolrCore core = h.getCore();
+    UpdateHandler updater = core.getUpdateHandler();
+    CommitUpdateCommand cmtCmd = new CommitUpdateCommand(false);
+    cmtCmd.waitSearcher = true;
+    updater.commit(cmtCmd);
+
+    addSimpleDoc("B");
+
+    // rollback "B"
+    RollbackUpdateCommand rbkCmd = new RollbackUpdateCommand();
+    updater.rollback(rbkCmd);
+    updater.commit(cmtCmd);
+    
+    // search - "B" should not be found.
+    Map<String,String> args = new HashMap<String, String>();
+    args.put( CommonParams.Q, "id:A OR id:B" );
+    args.put( "indent", "true" );
+    SolrQueryRequest req = new LocalSolrQueryRequest( core, new MapSolrParams( args) );
+    assertQ("\"B\" should not be found.", req
+            ,"//*[@numFound='1']"
+            ,"//result/doc[1]/int[@name='id'][.='A']"
+            );
+  }
+
+  public void testDeleteRollback() throws Exception {
+    addSimpleDoc("A");
+    addSimpleDoc("B");
+
+    // commit "A", "B"
+    SolrCore core = h.getCore();
+    UpdateHandler updater = core.getUpdateHandler();
+    CommitUpdateCommand cmtCmd = new CommitUpdateCommand(false);
+    cmtCmd.waitSearcher = true;
+    updater.commit(cmtCmd);
+
+    // search - "A","B" should be found.
+    Map<String,String> args = new HashMap<String, String>();
+    args.put( CommonParams.Q, "id:A OR id:B" );
+    args.put( "indent", "true" );
+    SolrQueryRequest req = new LocalSolrQueryRequest( core, new MapSolrParams( args) );
+    assertQ("\"A\" and \"B\" should be found.", req
+            ,"//*[@numFound='2']"
+            ,"//result/doc[1]/int[@name='id'][.='A']"
+            ,"//result/doc[2]/int[@name='id'][.='B']"
+            );
+
+    // delete "B"
+    deleteSimpleDoc("B");
+    
+    // search - "A","B" should be found.
+    assertQ("\"A\" and \"B\" should be found.", req
+        ,"//*[@numFound='2']"
+        ,"//result/doc[1]/int[@name='id'][.='A']"
+        ,"//result/doc[2]/int[@name='id'][.='B']"
+        );
+
+    // rollback "B"
+    RollbackUpdateCommand rbkCmd = new RollbackUpdateCommand();
+    updater.rollback(rbkCmd);
+    updater.commit(cmtCmd);
+    
+    // search - "B" should be found.
+    assertQ("\"B\" should be found.", req
+        ,"//*[@numFound='2']"
+        ,"//result/doc[1]/int[@name='id'][.='A']"
+        ,"//result/doc[2]/int[@name='id'][.='B']"
+        );
+  }
   
+  private void addSimpleDoc(String id) throws Exception {
+    SolrCore core = h.getCore();
+    
+    UpdateHandler updater = core.getUpdateHandler();
+    
+    AddUpdateCommand cmd = new AddUpdateCommand();
+    cmd.overwriteCommitted = true;
+    cmd.overwritePending = true;
+    cmd.allowDups = false;
+    
+    // Add a document
+    cmd.doc = new Document();
+    cmd.doc.add( new Field( "id", id, Store.YES, Index.UN_TOKENIZED ) );
+    updater.addDoc( cmd );
+  }
+  
+  private void deleteSimpleDoc(String id) throws Exception {
+    SolrCore core = h.getCore();
+    
+    UpdateHandler updater = core.getUpdateHandler();
+    
+    // Delete the document
+    DeleteUpdateCommand cmd = new DeleteUpdateCommand();
+    cmd.id = id;
+    cmd.fromCommitted = true;
+    cmd.fromPending = true;
+    
+    updater.delete(cmd);
+  }
 }