* 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.

*/

* Helper utility to build protocol buffer requests,

* or build components for protocol buffer requests.

*/

  private RequestConverter() {

  }

   * Create a new protocol buffer GetRequest to get a row, all columns in a family.

   * If there is no such row, return the closest row before it.

   *

   * @param regionName the name of the region to get

   * @param row the row to get

   * @param family the column family to get

   * should return the immediate row before

   * @return a protocol buffer GetReuqest

   */

  public static GetRequest buildGetRowOrBeforeRequest(

      final byte[] regionName, final byte[] row, final byte[] family) {

    GetRequest.Builder builder = GetRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    Column.Builder columnBuilder = Column.newBuilder();

    columnBuilder.setFamily(HBaseZeroCopyByteString.wrap(family));

    ClientProtos.Get.Builder getBuilder =

      ClientProtos.Get.newBuilder();

    getBuilder.setRow(HBaseZeroCopyByteString.wrap(row));

    getBuilder.addColumn(columnBuilder.build());

    getBuilder.setClosestRowBefore(true);

    builder.setGet(getBuilder.build());

    return builder.build();

  }

  /**

   * Create a protocol buffer GetRequest for a client Get

   *

   * @param regionName the name of the region to get

   * @param get the client Get

   * @return a protocol buffer GetRequest

   */

  public static GetRequest buildGetRequest(final byte[] regionName,

      final Get get) throws IOException {

    GetRequest.Builder builder = GetRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    builder.setGet(ProtobufUtil.toGet(get));

    return builder.build();

  }

  /**

   * Create a protocol buffer MutateRequest for a client increment

   *

   * @param regionName

   * @param row

   * @param family

   * @param qualifier

   * @param amount

   * @param durability

   * @return a mutate request

   */

  public static MutateRequest buildIncrementRequest(

      final byte[] regionName, final byte[] row, final byte[] family, final byte[] qualifier,

      final long amount, final Durability durability, long nonceGroup, long nonce) {

    MutateRequest.Builder builder = MutateRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    MutationProto.Builder mutateBuilder = MutationProto.newBuilder();

    mutateBuilder.setRow(HBaseZeroCopyByteString.wrap(row));

    mutateBuilder.setMutateType(MutationType.INCREMENT);

    mutateBuilder.setDurability(ProtobufUtil.toDurability(durability));

    ColumnValue.Builder columnBuilder = ColumnValue.newBuilder();

    columnBuilder.setFamily(HBaseZeroCopyByteString.wrap(family));

    QualifierValue.Builder valueBuilder = QualifierValue.newBuilder();

    valueBuilder.setValue(HBaseZeroCopyByteString.wrap(Bytes.toBytes(amount)));

    valueBuilder.setQualifier(HBaseZeroCopyByteString.wrap(qualifier));

    columnBuilder.addQualifierValue(valueBuilder.build());

    mutateBuilder.addColumnValue(columnBuilder.build());

    if (nonce != HConstants.NO_NONCE) {

      mutateBuilder.setNonce(nonce);

    }

    builder.setMutation(mutateBuilder.build());

    if (nonceGroup != HConstants.NO_NONCE) {

      builder.setNonceGroup(nonceGroup);

    }

    return builder.build();

  }

  /**

   * Create a protocol buffer MutateRequest for a conditioned put

   *

   * @param regionName

   * @param row

   * @param family

   * @param qualifier

   * @param comparator

   * @param compareType

   * @param put

   * @return a mutate request

   * @throws IOException

   */

  public static MutateRequest buildMutateRequest(

      final byte[] regionName, final byte[] row, final byte[] family,

      final byte [] qualifier, final ByteArrayComparable comparator,

      final CompareType compareType, final Put put) throws IOException {

    MutateRequest.Builder builder = MutateRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    Condition condition = buildCondition(

      row, family, qualifier, comparator, compareType);

    builder.setMutation(ProtobufUtil.toMutation(MutationType.PUT, put, MutationProto.newBuilder()));

    builder.setCondition(condition);

    return builder.build();

  }

  /**

   * Create a protocol buffer MutateRequest for a conditioned delete

   *

   * @param regionName

   * @param row

   * @param family

   * @param qualifier

   * @param comparator

   * @param compareType

   * @param delete

   * @return a mutate request

   * @throws IOException

   */

  public static MutateRequest buildMutateRequest(

      final byte[] regionName, final byte[] row, final byte[] family,

      final byte [] qualifier, final ByteArrayComparable comparator,

      final CompareType compareType, final Delete delete) throws IOException {

    MutateRequest.Builder builder = MutateRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    Condition condition = buildCondition(

      row, family, qualifier, comparator, compareType);

    builder.setMutation(ProtobufUtil.toMutation(MutationType.DELETE, delete,

      MutationProto.newBuilder()));

    builder.setCondition(condition);

    return builder.build();

  }

  /**

   * Create a protocol buffer MutateRequest for a put

   *

   * @param regionName

   * @param put

   * @return a mutate request

   * @throws IOException

   */

  public static MutateRequest buildMutateRequest(

      final byte[] regionName, final Put put) throws IOException {

    MutateRequest.Builder builder = MutateRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    builder.setMutation(ProtobufUtil.toMutation(MutationType.PUT, put, MutationProto.newBuilder()));

    return builder.build();

  }

  /**

   * Create a protocol buffer MutateRequest for an append

   *

   * @param regionName

   * @param append

   * @return a mutate request

   * @throws IOException

   */

  public static MutateRequest buildMutateRequest(final byte[] regionName,

      final Append append, long nonceGroup, long nonce) throws IOException {

    MutateRequest.Builder builder = MutateRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    if (nonce != HConstants.NO_NONCE && nonceGroup != HConstants.NO_NONCE) {

      builder.setNonceGroup(nonceGroup);

    }

    builder.setMutation(ProtobufUtil.toMutation(MutationType.APPEND, append,

      MutationProto.newBuilder(), nonce));

    return builder.build();

  }

  /**

   * Create a protocol buffer MutateRequest for a client increment

   *

   * @param regionName

   * @param increment

   * @return a mutate request

   */

  public static MutateRequest buildMutateRequest(final byte[] regionName,

      final Increment increment, final long nonceGroup, final long nonce) {

    MutateRequest.Builder builder = MutateRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    if (nonce != HConstants.NO_NONCE && nonceGroup != HConstants.NO_NONCE) {

      builder.setNonceGroup(nonceGroup);

    }

    builder.setMutation(ProtobufUtil.toMutation(increment, MutationProto.newBuilder(), nonce));

    return builder.build();

  }

  /**

   * Create a protocol buffer MutateRequest for a delete

   *

   * @param regionName

   * @param delete

   * @return a mutate request

   * @throws IOException

   */

  public static MutateRequest buildMutateRequest(

      final byte[] regionName, final Delete delete) throws IOException {

    MutateRequest.Builder builder = MutateRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    builder.setMutation(ProtobufUtil.toMutation(MutationType.DELETE, delete,

      MutationProto.newBuilder()));

    return builder.build();

  }

  /**

   * Create a protocol buffer MultiRequest for row mutations.

   * Does not propagate Action absolute position.  Does not set atomic action on the created

   * RegionAtomic.  Caller should do that if wanted.

   * @param regionName

   * @param rowMutations

   * @return a data-laden RegionMutation.Builder

   * @throws IOException

   */

  public static RegionAction.Builder buildRegionAction(final byte [] regionName,

      final RowMutations rowMutations)

  throws IOException {

    RegionAction.Builder builder =

      getRegionActionBuilderWithRegion(RegionAction.newBuilder(), regionName);

    ClientProtos.Action.Builder actionBuilder = ClientProtos.Action.newBuilder();

    MutationProto.Builder mutationBuilder = MutationProto.newBuilder();

    for (Mutation mutation: rowMutations.getMutations()) {

      MutationType mutateType = null;

      if (mutation instanceof Put) {

        mutateType = MutationType.PUT;

      } else if (mutation instanceof Delete) {

        mutateType = MutationType.DELETE;

      } else {

        throw new DoNotRetryIOException("RowMutations supports only put and delete, not " +

          mutation.getClass().getName());

      }

      mutationBuilder.clear();

      MutationProto mp = ProtobufUtil.toMutation(mutateType, mutation, mutationBuilder);

      actionBuilder.clear();

      actionBuilder.setMutation(mp);

      builder.addAction(actionBuilder.build());

    }

    return builder;

  }

  /**

   * Create a protocol buffer MultiRequest for row mutations that does not hold data.  Data/Cells

   * are carried outside of protobuf.  Return references to the Cells in <code>cells</code> param.

    * Does not propagate Action absolute position.  Does not set atomic action on the created

   * RegionAtomic.  Caller should do that if wanted.

   * @param regionName

   * @param rowMutations

   * @param cells Return in here a list of Cells as CellIterable.

   * @return a region mutation minus data

   * @throws IOException

   */

  public static RegionAction.Builder buildNoDataRegionAction(final byte[] regionName,

      final RowMutations rowMutations, final List<CellScannable> cells,

      final RegionAction.Builder regionActionBuilder,

      final ClientProtos.Action.Builder actionBuilder,

      final MutationProto.Builder mutationBuilder)

  throws IOException {

    for (Mutation mutation: rowMutations.getMutations()) {

      MutationType type = null;

      if (mutation instanceof Put) {

        type = MutationType.PUT;

      } else if (mutation instanceof Delete) {

        type = MutationType.DELETE;

      } else {

        throw new DoNotRetryIOException("RowMutations supports only put and delete, not " +

          mutation.getClass().getName());

      }

      mutationBuilder.clear();

      MutationProto mp = ProtobufUtil.toMutationNoData(type, mutation, mutationBuilder);

      cells.add(mutation);

      actionBuilder.clear();

      regionActionBuilder.addAction(actionBuilder.setMutation(mp).build());

    }

    return regionActionBuilder;

  }

  private static RegionAction.Builder getRegionActionBuilderWithRegion(

      final RegionAction.Builder regionActionBuilder, final byte [] regionName) {

    RegionSpecifier region = buildRegionSpecifier(RegionSpecifierType.REGION_NAME, regionName);

    regionActionBuilder.setRegion(region);

    return regionActionBuilder;

  }

  /**

   * Create a protocol buffer ScanRequest for a client Scan

   *

   * @param regionName

   * @param scan

   * @param numberOfRows

   * @param closeScanner

   * @return a scan request

   * @throws IOException

   */

  public static ScanRequest buildScanRequest(final byte[] regionName,

      final Scan scan, final int numberOfRows,

        final boolean closeScanner) throws IOException {

    ScanRequest.Builder builder = ScanRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setNumberOfRows(numberOfRows);

    builder.setCloseScanner(closeScanner);

    builder.setRegion(region);

    builder.setScan(ProtobufUtil.toScan(scan));

    return builder.build();

  }

  /**

   * Create a protocol buffer ScanRequest for a scanner id

   *

   * @param scannerId

   * @param numberOfRows

   * @param closeScanner

   * @return a scan request

   */

  public static ScanRequest buildScanRequest(final long scannerId,

      final int numberOfRows, final boolean closeScanner) {

    ScanRequest.Builder builder = ScanRequest.newBuilder();

    builder.setNumberOfRows(numberOfRows);

    builder.setCloseScanner(closeScanner);

    builder.setScannerId(scannerId);

    return builder.build();

  }

  /**

   * Create a protocol buffer ScanRequest for a scanner id

   *

   * @param scannerId

   * @param numberOfRows

   * @param closeScanner

   * @param nextCallSeq

   * @return a scan request

   */

  public static ScanRequest buildScanRequest(final long scannerId, final int numberOfRows,

      final boolean closeScanner, final long nextCallSeq) {

    ScanRequest.Builder builder = ScanRequest.newBuilder();

    builder.setNumberOfRows(numberOfRows);

    builder.setCloseScanner(closeScanner);

    builder.setScannerId(scannerId);

    builder.setNextCallSeq(nextCallSeq);

    return builder.build();

  }

  /**

   * Create a protocol buffer bulk load request

   *

   * @param familyPaths

   * @param regionName

   * @param assignSeqNum

   * @return a bulk load request

   */

  public static BulkLoadHFileRequest buildBulkLoadHFileRequest(

      final List<Pair<byte[], String>> familyPaths,

      final byte[] regionName, boolean assignSeqNum) {

    BulkLoadHFileRequest.Builder builder = BulkLoadHFileRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    FamilyPath.Builder familyPathBuilder = FamilyPath.newBuilder();

    for (Pair<byte[], String> familyPath: familyPaths) {

      familyPathBuilder.setFamily(HBaseZeroCopyByteString.wrap(familyPath.getFirst()));

      familyPathBuilder.setPath(familyPath.getSecond());

      builder.addFamilyPath(familyPathBuilder.build());

    }

    builder.setAssignSeqNum(assignSeqNum);

    return builder.build();

  }

  /**

   * Create a protocol buffer multi request for a list of actions.

   * Propagates Actions original index.

   *

   * @param regionName

   * @param actions

   * @return a multi request

   * @throws IOException

   */

  public static <R> RegionAction.Builder buildRegionAction(final byte[] regionName,

      final List<Action<R>> actions, final RegionAction.Builder regionActionBuilder,

      final ClientProtos.Action.Builder actionBuilder,

      final MutationProto.Builder mutationBuilder) throws IOException {

    for (Action<R> action: actions) {

      Row row = action.getAction();

      actionBuilder.clear();

      actionBuilder.setIndex(action.getOriginalIndex());

      mutationBuilder.clear();

      if (row instanceof Get) {

        Get g = (Get)row;

        regionActionBuilder.addAction(actionBuilder.setGet(ProtobufUtil.toGet(g)));

      } else if (row instanceof Put) {

        regionActionBuilder.addAction(actionBuilder.

          setMutation(ProtobufUtil.toMutation(MutationType.PUT, (Put)row, mutationBuilder)));

      } else if (row instanceof Delete) {

        regionActionBuilder.addAction(actionBuilder.

          setMutation(ProtobufUtil.toMutation(MutationType.DELETE, (Delete)row, mutationBuilder)));

      } else if (row instanceof Append) {

        regionActionBuilder.addAction(actionBuilder.setMutation(ProtobufUtil.toMutation(

            MutationType.APPEND, (Append)row, mutationBuilder, action.getNonce())));

      } else if (row instanceof Increment) {

        regionActionBuilder.addAction(actionBuilder.setMutation(

            ProtobufUtil.toMutation((Increment)row, mutationBuilder, action.getNonce())));

      } else if (row instanceof RowMutations) {

        throw new UnsupportedOperationException("No RowMutations in multi calls; use mutateRow");

      } else {

        throw new DoNotRetryIOException("Multi doesn't support " + row.getClass().getName());

      }

    }

    return regionActionBuilder;

  }

  /**

   * Create a protocol buffer multirequest with NO data for a list of actions (data is carried

   * otherwise than via protobuf).  This means it just notes attributes, whether to write the

   * WAL, etc., and the presence in protobuf serves as place holder for the data which is

   * coming along otherwise.  Note that Get is different.  It does not contain 'data' and is always

   * carried by protobuf.  We return references to the data by adding them to the passed in

   * <code>data</code> param.

   *

   * <p>Propagates Actions original index.

   *

   * @param regionName

   * @param actions

   * @param cells Place to stuff references to actual data.

   * @return a multi request that does not carry any data.

   * @throws IOException

   */

  public static <R> RegionAction.Builder buildNoDataRegionAction(final byte[] regionName,

      final List<Action<R>> actions, final List<CellScannable> cells,

      final RegionAction.Builder regionActionBuilder,

      final ClientProtos.Action.Builder actionBuilder,

      final MutationProto.Builder mutationBuilder) throws IOException {

    RegionAction.Builder builder = getRegionActionBuilderWithRegion(

      RegionAction.newBuilder(), regionName);

    for (Action<R> action: actions) {

      Row row = action.getAction();

      actionBuilder.clear();

      actionBuilder.setIndex(action.getOriginalIndex());

      mutationBuilder.clear();

      if (row instanceof Get) {

        Get g = (Get)row;

        builder.addAction(actionBuilder.setGet(ProtobufUtil.toGet(g)));

      } else if (row instanceof Put) {

        Put p = (Put)row;

        cells.add(p);

        builder.addAction(actionBuilder.

          setMutation(ProtobufUtil.toMutationNoData(MutationType.PUT, p, mutationBuilder)));

      } else if (row instanceof Delete) {

        Delete d = (Delete)row;

        int size = d.size();

        // Note that a legitimate Delete may have a size of zero; i.e. a Delete that has nothing

        // in it but the row to delete.  In this case, the current implementation does not make

        // a KeyValue to represent a delete-of-all-the-row until we serialize... For such cases

        // where the size returned is zero, we will send the Delete fully pb'd rather than have

        // metadata only in the pb and then send the kv along the side in cells.

        if (size > 0) {

          cells.add(d);

          builder.addAction(actionBuilder.

            setMutation(ProtobufUtil.toMutationNoData(MutationType.DELETE, d, mutationBuilder)));

        } else {

          builder.addAction(actionBuilder.

            setMutation(ProtobufUtil.toMutation(MutationType.DELETE, d, mutationBuilder)));

        }

      } else if (row instanceof Append) {

        Append a = (Append)row;

        cells.add(a);

        builder.addAction(actionBuilder.setMutation(ProtobufUtil.toMutationNoData(

          MutationType.APPEND, a, mutationBuilder, action.getNonce())));

      } else if (row instanceof Increment) {

        Increment i = (Increment)row;

        cells.add(i);

        builder.addAction(actionBuilder.setMutation(ProtobufUtil.toMutationNoData(

          MutationType.INCREMENT, i, mutationBuilder, action.getNonce())));

      } else if (row instanceof RowMutations) {

        continue; // ignore RowMutations

      } else {

        throw new DoNotRetryIOException("Multi doesn't support " + row.getClass().getName());

      }

    }

    return builder;

  }

//Start utilities for Admin

  /**

   * Create a protocol buffer GetRegionInfoRequest for a given region name

   *

   * @param regionName the name of the region to get info

   * @return a protocol buffer GetRegionInfoRequest

   */

  public static GetRegionInfoRequest

      buildGetRegionInfoRequest(final byte[] regionName) {

    return buildGetRegionInfoRequest(regionName, false);

  }

  /**

   * Create a protocol buffer GetRegionInfoRequest for a given region name

   *

   * @param regionName the name of the region to get info

   * @param includeCompactionState indicate if the compaction state is requested

   * @return a protocol buffer GetRegionInfoRequest

   */

  public static GetRegionInfoRequest

      buildGetRegionInfoRequest(final byte[] regionName,

        final boolean includeCompactionState) {

    GetRegionInfoRequest.Builder builder = GetRegionInfoRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    if (includeCompactionState) {

      builder.setCompactionState(includeCompactionState);

    }

    return builder.build();

  }

/**

  * Create a protocol buffer GetStoreFileRequest for a given region name

  *

  * @param regionName the name of the region to get info

  * @param family the family to get store file list

  * @return a protocol buffer GetStoreFileRequest

  */

public static GetStoreFileRequest

     buildGetStoreFileRequest(final byte[] regionName, final byte[] family) {

   GetStoreFileRequest.Builder builder = GetStoreFileRequest.newBuilder();

   RegionSpecifier region = buildRegionSpecifier(

     RegionSpecifierType.REGION_NAME, regionName);

   builder.setRegion(region);

   builder.addFamily(HBaseZeroCopyByteString.wrap(family));

   return builder.build();

}

/**

  * Create a protocol buffer GetOnlineRegionRequest

  *

  * @return a protocol buffer GetOnlineRegionRequest

  */

public static GetOnlineRegionRequest buildGetOnlineRegionRequest() {

   return GetOnlineRegionRequest.newBuilder().build();

}

/**

  * Create a protocol buffer FlushRegionRequest for a given region name

  *

  * @param regionName the name of the region to get info

  * @return a protocol buffer FlushRegionRequest

  */

public static FlushRegionRequest

     buildFlushRegionRequest(final byte[] regionName) {

   FlushRegionRequest.Builder builder = FlushRegionRequest.newBuilder();

   RegionSpecifier region = buildRegionSpecifier(

     RegionSpecifierType.REGION_NAME, regionName);

   builder.setRegion(region);

   return builder.build();

}

/**

  * Create a protocol buffer OpenRegionRequest to open a list of regions

  *

  * @param regionOpenInfos info of a list of regions to open

  * @return a protocol buffer OpenRegionRequest

  */

public static OpenRegionRequest

     buildOpenRegionRequest(final List<Triple<HRegionInfo, Integer,

         List<ServerName>>> regionOpenInfos) {

   OpenRegionRequest.Builder builder = OpenRegionRequest.newBuilder();

   for (Triple<HRegionInfo, Integer, List<ServerName>> regionOpenInfo: regionOpenInfos) {

     Integer second = regionOpenInfo.getSecond();

     int versionOfOfflineNode = second == null ? -1 : second.intValue();

     builder.addOpenInfo(buildRegionOpenInfo(

       regionOpenInfo.getFirst(), versionOfOfflineNode, regionOpenInfo.getThird()));

   }

   return builder.build();

}

/**

  * Create a protocol buffer OpenRegionRequest for a given region

  *

  * @param region the region to open

* @param versionOfOfflineNode that needs to be present in the offline node

* @param favoredNodes

  * @return a protocol buffer OpenRegionRequest

  */

public static OpenRegionRequest buildOpenRegionRequest(

     final HRegionInfo region, final int versionOfOfflineNode, List<ServerName> favoredNodes) {

   OpenRegionRequest.Builder builder = OpenRegionRequest.newBuilder();

   builder.addOpenInfo(buildRegionOpenInfo(region, versionOfOfflineNode, favoredNodes));

   return builder.build();

}

/**

  * Create a protocol buffer UpdateFavoredNodesRequest to update a list of favorednode mappings

  * @param updateRegionInfos

  * @return a protocol buffer UpdateFavoredNodesRequest

  */

public static UpdateFavoredNodesRequest buildUpdateFavoredNodesRequest(

     final List<Pair<HRegionInfo, List<ServerName>>> updateRegionInfos) {

   UpdateFavoredNodesRequest.Builder ubuilder = UpdateFavoredNodesRequest.newBuilder();

   for (Pair<HRegionInfo, List<ServerName>> pair : updateRegionInfos) {

     RegionUpdateInfo.Builder builder = RegionUpdateInfo.newBuilder();

     builder.setRegion(HRegionInfo.convert(pair.getFirst()));

     for (ServerName server : pair.getSecond()) {

       builder.addFavoredNodes(ProtobufUtil.toServerName(server));

     }

     ubuilder.addUpdateInfo(builder.build());

   }

   return ubuilder.build();

}

/**

  * Create a CloseRegionRequest for a given region name

  *

  * @param regionName the name of the region to close

  * @param transitionInZK indicator if to transition in ZK

  * @return a CloseRegionRequest

  */

public static CloseRegionRequest buildCloseRegionRequest(

     final byte[] regionName, final boolean transitionInZK) {

   CloseRegionRequest.Builder builder = CloseRegionRequest.newBuilder();

   RegionSpecifier region = buildRegionSpecifier(

     RegionSpecifierType.REGION_NAME, regionName);

   builder.setRegion(region);

   builder.setTransitionInZK(transitionInZK);

   return builder.build();

}

  public static CloseRegionRequest buildCloseRegionRequest(

    final byte[] regionName, final int versionOfClosingNode,

    ServerName destinationServer, final boolean transitionInZK) {

    CloseRegionRequest.Builder builder = CloseRegionRequest.newBuilder();

    RegionSpecifier region = buildRegionSpecifier(

      RegionSpecifierType.REGION_NAME, regionName);

    builder.setRegion(region);

    builder.setVersionOfClosingNode(versionOfClosingNode);

    builder.setTransitionInZK(transitionInZK);

    if (destinationServer != null){

      builder.setDestinationServer(ProtobufUtil.toServerName( destinationServer) );

    }

    return builder.build();

  }

/**

  * Create a CloseRegionRequest for a given encoded region name

  *

  * @param encodedRegionName the name of the region to close

  * @param transitionInZK indicator if to transition in ZK

  * @return a CloseRegionRequest

  */

public static CloseRegionRequest

     buildCloseRegionRequest(final String encodedRegionName,

       final boolean transitionInZK) {

   CloseRegionRequest.Builder builder = CloseRegionRequest.newBuilder();

   RegionSpecifier region = buildRegionSpecifier(

     RegionSpecifierType.ENCODED_REGION_NAME,

     Bytes.toBytes(encodedRegionName));

   builder.setRegion(region);

   builder.setTransitionInZK(transitionInZK);

   return builder.build();

}

/**

  * Create a SplitRegionRequest for a given region name

  *

  * @param regionName the name of the region to split

  * @param splitPoint the split point

  * @return a SplitRegionRequest

  */

public static SplitRegionRequest buildSplitRegionRequest(

     final byte[] regionName, final byte[] splitPoint) {

   SplitRegionRequest.Builder builder = SplitRegionRequest.newBuilder();

   RegionSpecifier region = buildRegionSpecifier(

     RegionSpecifierType.REGION_NAME, regionName);

   builder.setRegion(region);

   if (splitPoint != null) {

     builder.setSplitPoint(HBaseZeroCopyByteString.wrap(splitPoint));

   }

   return builder.build();

}

  /**

   * Create a MergeRegionsRequest for the given regions

   * @param regionA name of region a

   * @param regionB name of region b

   * @param forcible true if it is a compulsory merge

   * @return a MergeRegionsRequest

   */

  public static MergeRegionsRequest buildMergeRegionsRequest(

      final byte[] regionA, final byte[] regionB, final boolean forcible) {

    MergeRegionsRequest.Builder builder = MergeRegionsRequest.newBuilder();

    RegionSpecifier regionASpecifier = buildRegionSpecifier(

        RegionSpecifierType.REGION_NAME, regionA);

    RegionSpecifier regionBSpecifier = buildRegionSpecifier(

        RegionSpecifierType.REGION_NAME, regionB);

    builder.setRegionA(regionASpecifier);

    builder.setRegionB(regionBSpecifier);

    builder.setForcible(forcible);

    return builder.build();

  }

/**

  * Create a  CompactRegionRequest for a given region name

  *

  * @param regionName the name of the region to get info

  * @param major indicator if it is a major compaction

  * @return a CompactRegionRequest

  */

public static CompactRegionRequest buildCompactRegionRequest(

     final byte[] regionName, final boolean major, final byte [] family) {

   CompactRegionRequest.Builder builder = CompactRegionRequest.newBuilder();

   RegionSpecifier region = buildRegionSpecifier(

     RegionSpecifierType.REGION_NAME, regionName);

   builder.setRegion(region);

   builder.setMajor(major);

   if (family != null) {

     builder.setFamily(HBaseZeroCopyByteString.wrap(family));

   }

   return builder.build();

}

/**

  * @see {@link #buildRollWALWriterRequest()

  */

private static RollWALWriterRequest ROLL_WAL_WRITER_REQUEST =

     RollWALWriterRequest.newBuilder().build();

  /**

  * Create a new RollWALWriterRequest

  *

  * @return a ReplicateWALEntryRequest

  */

public static RollWALWriterRequest buildRollWALWriterRequest() {

   return ROLL_WAL_WRITER_REQUEST;

}

/**

  * @see {@link #buildGetServerInfoRequest()}

  */

private static GetServerInfoRequest GET_SERVER_INFO_REQUEST =

   GetServerInfoRequest.newBuilder().build();

/**

  * Create a new GetServerInfoRequest

  *

  * @return a GetServerInfoRequest

  */

public static GetServerInfoRequest buildGetServerInfoRequest() {

   return GET_SERVER_INFO_REQUEST;

}

/**

  * Create a new StopServerRequest

  *

  * @param reason the reason to stop the server

  * @return a StopServerRequest

  */

public static StopServerRequest buildStopServerRequest(final String reason) {

   StopServerRequest.Builder builder = StopServerRequest.newBuilder();

   builder.setReason(reason);

   return builder.build();

}

  /**

   * Convert a byte array to a protocol buffer RegionSpecifier

   *

   * @param type the region specifier type

   * @param value the region specifier byte array value

   * @return a protocol buffer RegionSpecifier

   */

  public static RegionSpecifier buildRegionSpecifier(

      final RegionSpecifierType type, final byte[] value) {

    RegionSpecifier.Builder regionBuilder = RegionSpecifier.newBuilder();

    regionBuilder.setValue(HBaseZeroCopyByteString.wrap(value));

    regionBuilder.setType(type);

    return regionBuilder.build();

  }

  /**

   * Create a protocol buffer Condition

   *

   * @param row

   * @param family

   * @param qualifier

   * @param comparator

   * @param compareType

   * @return a Condition

   * @throws IOException

   */

  private static Condition buildCondition(final byte[] row,

      final byte[] family, final byte [] qualifier,

      final ByteArrayComparable comparator,

      final CompareType compareType) throws IOException {

    Condition.Builder builder = Condition.newBuilder();

    builder.setRow(HBaseZeroCopyByteString.wrap(row));

    builder.setFamily(HBaseZeroCopyByteString.wrap(family));

    builder.setQualifier(HBaseZeroCopyByteString.wrap(qualifier));

    builder.setComparator(ProtobufUtil.toComparator(comparator));

    builder.setCompareType(compareType);

    return builder.build();

  }

  /**

   * Create a protocol buffer AddColumnRequest

   *

   * @param tableName

   * @param column

   * @return an AddColumnRequest

   */

  public static AddColumnRequest buildAddColumnRequest(

      final TableName tableName, final HColumnDescriptor column) {

    AddColumnRequest.Builder builder = AddColumnRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName(tableName));

    builder.setColumnFamilies(column.convert());

    return builder.build();

  }

  /**

   * Create a protocol buffer DeleteColumnRequest

   *

   * @param tableName

   * @param columnName

   * @return a DeleteColumnRequest

   */

  public static DeleteColumnRequest buildDeleteColumnRequest(

      final TableName tableName, final byte [] columnName) {

    DeleteColumnRequest.Builder builder = DeleteColumnRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName((tableName)));

    builder.setColumnName(HBaseZeroCopyByteString.wrap(columnName));

    return builder.build();

  }

  /**

   * Create a protocol buffer ModifyColumnRequest

   *

   * @param tableName

   * @param column

   * @return an ModifyColumnRequest

   */

  public static ModifyColumnRequest buildModifyColumnRequest(

      final TableName tableName, final HColumnDescriptor column) {

    ModifyColumnRequest.Builder builder = ModifyColumnRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName((tableName)));

    builder.setColumnFamilies(column.convert());

    return builder.build();

  }

  /**

   * Create a protocol buffer MoveRegionRequest

   *

   * @param encodedRegionName

   * @param destServerName

   * @return A MoveRegionRequest

   * @throws DeserializationException

   */

  public static MoveRegionRequest buildMoveRegionRequest(

      final byte [] encodedRegionName, final byte [] destServerName) throws

      DeserializationException {

  MoveRegionRequest.Builder builder = MoveRegionRequest.newBuilder();

    builder.setRegion(

      buildRegionSpecifier(RegionSpecifierType.ENCODED_REGION_NAME,encodedRegionName));

    if (destServerName != null) {

      builder.setDestServerName(

        ProtobufUtil.toServerName(ServerName.valueOf(Bytes.toString(destServerName))));

    }

    return builder.build();

  }

  public static DispatchMergingRegionsRequest buildDispatchMergingRegionsRequest(

      final byte[] encodedNameOfRegionA, final byte[] encodedNameOfRegionB,

      final boolean forcible) throws DeserializationException {

    DispatchMergingRegionsRequest.Builder builder = DispatchMergingRegionsRequest.newBuilder();

    builder.setRegionA(buildRegionSpecifier(

        RegionSpecifierType.ENCODED_REGION_NAME, encodedNameOfRegionA));

    builder.setRegionB(buildRegionSpecifier(

        RegionSpecifierType.ENCODED_REGION_NAME, encodedNameOfRegionB));

    builder.setForcible(forcible);

    return builder.build();

  }

  /**

   * Create a protocol buffer AssignRegionRequest

   *

   * @param regionName

   * @return an AssignRegionRequest

   */

  public static AssignRegionRequest buildAssignRegionRequest(final byte [] regionName) {

    AssignRegionRequest.Builder builder = AssignRegionRequest.newBuilder();

    builder.setRegion(buildRegionSpecifier(RegionSpecifierType.REGION_NAME,regionName));

    return builder.build();

  }

  /**

   * Creates a protocol buffer UnassignRegionRequest

   *

   * @param regionName

   * @param force

   * @return an UnassignRegionRequest

   */

  public static UnassignRegionRequest buildUnassignRegionRequest(

      final byte [] regionName, final boolean force) {

    UnassignRegionRequest.Builder builder = UnassignRegionRequest.newBuilder();

    builder.setRegion(buildRegionSpecifier(RegionSpecifierType.REGION_NAME,regionName));

    builder.setForce(force);

    return builder.build();

  }

  /**

   * Creates a protocol buffer OfflineRegionRequest

   *

   * @param regionName

   * @return an OfflineRegionRequest

   */

  public static OfflineRegionRequest buildOfflineRegionRequest(final byte [] regionName) {

    OfflineRegionRequest.Builder builder = OfflineRegionRequest.newBuilder();

    builder.setRegion(buildRegionSpecifier(RegionSpecifierType.REGION_NAME,regionName));

    return builder.build();

  }

  /**

   * Creates a protocol buffer DeleteTableRequest

   *

   * @param tableName

   * @return a DeleteTableRequest

   */

  public static DeleteTableRequest buildDeleteTableRequest(final TableName tableName) {

    DeleteTableRequest.Builder builder = DeleteTableRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName(tableName));

    return builder.build();

  }

  /**

   * Creates a protocol buffer EnableTableRequest

   *

   * @param tableName

   * @return an EnableTableRequest

   */

  public static EnableTableRequest buildEnableTableRequest(final TableName tableName) {

    EnableTableRequest.Builder builder = EnableTableRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName(tableName));

    return builder.build();

  }

  /**

   * Creates a protocol buffer DisableTableRequest

   *

   * @param tableName

   * @return a DisableTableRequest

   */

  public static DisableTableRequest buildDisableTableRequest(final TableName tableName) {

    DisableTableRequest.Builder builder = DisableTableRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName((tableName)));

    return builder.build();

  }

  /**

   * Creates a protocol buffer CreateTableRequest

   *

   * @param hTableDesc

   * @param splitKeys

   * @return a CreateTableRequest

   */

  public static CreateTableRequest buildCreateTableRequest(

      final HTableDescriptor hTableDesc, final byte [][] splitKeys) {

    CreateTableRequest.Builder builder = CreateTableRequest.newBuilder();

    builder.setTableSchema(hTableDesc.convert());

    if (splitKeys != null) {

      for (byte [] splitKey : splitKeys) {

        builder.addSplitKeys(HBaseZeroCopyByteString.wrap(splitKey));

      }

    }

    return builder.build();

  }

  /**

   * Creates a protocol buffer ModifyTableRequest

   *

   * @param tableName

   * @param hTableDesc

   * @return a ModifyTableRequest

   */

  public static ModifyTableRequest buildModifyTableRequest(

      final TableName tableName, final HTableDescriptor hTableDesc) {

    ModifyTableRequest.Builder builder = ModifyTableRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName((tableName)));

    builder.setTableSchema(hTableDesc.convert());

    return builder.build();

  }

  /**

   * Creates a protocol buffer GetSchemaAlterStatusRequest

   *

   * @param tableName

   * @return a GetSchemaAlterStatusRequest

   */

  public static GetSchemaAlterStatusRequest buildGetSchemaAlterStatusRequest(

      final TableName tableName) {

    GetSchemaAlterStatusRequest.Builder builder = GetSchemaAlterStatusRequest.newBuilder();

    builder.setTableName(ProtobufUtil.toProtoTableName((tableName)));

    return builder.build();

  }

  /**

   * Creates a protocol buffer GetTableDescriptorsRequest

   *

   * @param tableNames

   * @return a GetTableDescriptorsRequest

   */

  public static GetTableDescriptorsRequest buildGetTableDescriptorsRequest(

      final List<TableName> tableNames) {

    GetTableDescriptorsRequest.Builder builder = GetTableDescriptorsRequest.newBuilder();

    if (tableNames != null) {

      for (TableName tableName : tableNames) {

        builder.addTableNames(ProtobufUtil.toProtoTableName(tableName));

      }

    }

    return builder.build();

  }

  /**

   * Creates a protocol buffer GetTableDescriptorsRequest for a single table

   *

   * @param tableName the table name

   * @return a GetTableDescriptorsRequest

   */

  public static GetTableDescriptorsRequest buildGetTableDescriptorsRequest(

      final TableName tableName) {

    return GetTableDescriptorsRequest.newBuilder()

      .addTableNames(ProtobufUtil.toProtoTableName(tableName))

      .build();

  }

  /**

   * Creates a protocol buffer IsMasterRunningRequest

   *

   * @return a IsMasterRunningRequest

   */

  public static IsMasterRunningRequest buildIsMasterRunningRequest() {

    return IsMasterRunningRequest.newBuilder().build();

  }

  /**

   * Creates a protocol buffer BalanceRequest

   *

   * @return a BalanceRequest

   */

  public static BalanceRequest buildBalanceRequest() {

    return BalanceRequest.newBuilder().build();

  }

  /**

   * Creates a protocol buffer SetBalancerRunningRequest

   *

   * @param on

   * @param synchronous

   * @return a SetBalancerRunningRequest

   */

  public static SetBalancerRunningRequest buildSetBalancerRunningRequest(boolean on, boolean synchronous) {

    return SetBalancerRunningRequest.newBuilder().setOn(on).setSynchronous(synchronous).build();

  }

  /**

   * @see {@link #buildGetClusterStatusRequest}

   */

  private static final GetClusterStatusRequest GET_CLUSTER_STATUS_REQUEST =

      GetClusterStatusRequest.newBuilder().build();

  /**

   * Creates a protocol buffer GetClusterStatusRequest

   *

   * @return A GetClusterStatusRequest

   */

  public static GetClusterStatusRequest buildGetClusterStatusRequest() {

    return GET_CLUSTER_STATUS_REQUEST;

  }

  /**

   * @see {@link #buildCatalogScanRequest}

   */

  private static final RunCatalogScanRequest CATALOG_SCAN_REQUEST =

    RunCatalogScanRequest.newBuilder().build();

  /**

   * Creates a request for running a catalog scan

   * @return A {@link RunCatalogScanRequest}

   */

  public static RunCatalogScanRequest buildCatalogScanRequest() {

    return CATALOG_SCAN_REQUEST;

  }

  /**

   * Creates a request for enabling/disabling the catalog janitor

   * @return A {@link EnableCatalogJanitorRequest}

   */

  public static EnableCatalogJanitorRequest buildEnableCatalogJanitorRequest(boolean enable) {

    return EnableCatalogJanitorRequest.newBuilder().setEnable(enable).build();

  }

  /**

   * @see {@link #buildIsCatalogJanitorEnabledRequest()}

   */

  private static final IsCatalogJanitorEnabledRequest IS_CATALOG_JANITOR_ENABLED_REQUEST =

    IsCatalogJanitorEnabledRequest.newBuilder().build();

  /**

   * Creates a request for querying the master whether the catalog janitor is enabled

   * @return A {@link IsCatalogJanitorEnabledRequest}

   */

  public static IsCatalogJanitorEnabledRequest buildIsCatalogJanitorEnabledRequest() {

    return IS_CATALOG_JANITOR_ENABLED_REQUEST;

  }

  /**

   * Creates a request for querying the master the last flushed sequence Id for a region

   * @param regionName

   * @return A {@link GetLastFlushedSequenceIdRequest}

   */

  public static GetLastFlushedSequenceIdRequest buildGetLastFlushedSequenceIdRequest(

      byte[] regionName) {

    return GetLastFlushedSequenceIdRequest.newBuilder().setRegionName(

        HBaseZeroCopyByteString.wrap(regionName)).build();

  }

  /**

   * Create a request to grant user permissions.

   *

   * @param username the short user name who to grant permissions

   * @param actions the permissions to be granted

   * @return A {@link AccessControlProtos} GrantRequest

   */

  public static AccessControlProtos.GrantRequest buildGrantRequest(

      String username, AccessControlProtos.Permission.Action... actions) {

    AccessControlProtos.Permission.Builder ret =

        AccessControlProtos.Permission.newBuilder();

    AccessControlProtos.GlobalPermission.Builder permissionBuilder =

        AccessControlProtos.GlobalPermission.newBuilder();

    for (AccessControlProtos.Permission.Action a : actions) {

      permissionBuilder.addAction(a);

    }

    ret.setType(AccessControlProtos.Permission.Type.Global)

       .setGlobalPermission(permissionBuilder);

    return AccessControlProtos.GrantRequest.newBuilder()

      .setUserPermission(

          AccessControlProtos.UserPermission.newBuilder()

              .setUser(ByteString.copyFromUtf8(username))

              .setPermission(ret)

      ).build();

  }

  /**

   * Create a request to grant user permissions.

   *

   * @param username the short user name who to grant permissions

   * @param tableName optional table name the permissions apply

   * @param family optional column family

   * @param qualifier optional qualifier

   * @param actions the permissions to be granted

   * @return A {@link AccessControlProtos} GrantRequest

   */

  public static AccessControlProtos.GrantRequest buildGrantRequest(

      String username, TableName tableName, byte[] family, byte[] qualifier,

      AccessControlProtos.Permission.Action... actions) {

    AccessControlProtos.Permission.Builder ret =

        AccessControlProtos.Permission.newBuilder();

    AccessControlProtos.TablePermission.Builder permissionBuilder =

        AccessControlProtos.TablePermission.newBuilder();

    for (AccessControlProtos.Permission.Action a : actions) {

      permissionBuilder.addAction(a);

    }

    if (tableName == null) {

      throw new NullPointerException("TableName cannot be null");

    }

    permissionBuilder.setTableName(ProtobufUtil.toProtoTableName(tableName));

    if (family != null) {

      permissionBuilder.setFamily(HBaseZeroCopyByteString.wrap(family));

    }

    if (qualifier != null) {

      permissionBuilder.setQualifier(HBaseZeroCopyByteString.wrap(qualifier));

    }

    ret.setType(AccessControlProtos.Permission.Type.Table)

       .setTablePermission(permissionBuilder);

    return AccessControlProtos.GrantRequest.newBuilder()

      .setUserPermission(

          AccessControlProtos.UserPermission.newBuilder()

              .setUser(ByteString.copyFromUtf8(username))

              .setPermission(ret)

      ).build();

  }

  /**

   * Create a request to grant user permissions.

   *

   * @param username the short user name who to grant permissions

   * @param namespace optional table name the permissions apply

   * @param actions the permissions to be granted

   * @return A {@link AccessControlProtos} GrantRequest

   */

  public static AccessControlProtos.GrantRequest buildGrantRequest(

      String username, String namespace,

      AccessControlProtos.Permission.Action... actions) {

    AccessControlProtos.Permission.Builder ret =

        AccessControlProtos.Permission.newBuilder();

    AccessControlProtos.NamespacePermission.Builder permissionBuilder =

        AccessControlProtos.NamespacePermission.newBuilder();

    for (AccessControlProtos.Permission.Action a : actions) {

      permissionBuilder.addAction(a);

    }

    if (namespace != null) {

      permissionBuilder.setNamespaceName(ByteString.copyFromUtf8(namespace));

    }

    ret.setType(AccessControlProtos.Permission.Type.Namespace)

       .setNamespacePermission(permissionBuilder);

    return AccessControlProtos.GrantRequest.newBuilder()

      .setUserPermission(

          AccessControlProtos.UserPermission.newBuilder()

              .setUser(ByteString.copyFromUtf8(username))

              .setPermission(ret)

      ).build();

  }

  /**

   * Create a request to revoke user permissions.

   *

   * @param username the short user name whose permissions to be revoked

   * @param actions the permissions to be revoked

   * @return A {@link AccessControlProtos} RevokeRequest

   */

  public static AccessControlProtos.RevokeRequest buildRevokeRequest(

      String username, AccessControlProtos.Permission.Action... actions) {

    AccessControlProtos.Permission.Builder ret =

        AccessControlProtos.Permission.newBuilder();

    AccessControlProtos.GlobalPermission.Builder permissionBuilder =

        AccessControlProtos.GlobalPermission.newBuilder();

    for (AccessControlProtos.Permission.Action a : actions) {

      permissionBuilder.addAction(a);

    }

    ret.setType(AccessControlProtos.Permission.Type.Global)

       .setGlobalPermission(permissionBuilder);

    return AccessControlProtos.RevokeRequest.newBuilder()

      .setUserPermission(

          AccessControlProtos.UserPermission.newBuilder()

              .setUser(ByteString.copyFromUtf8(username))

              .setPermission(ret)

      ).build();

  }

  /**

   * Create a request to revoke user permissions.

   *

   * @param username the short user name whose permissions to be revoked

   * @param tableName optional table name the permissions apply

   * @param family optional column family

   * @param qualifier optional qualifier

   * @param actions the permissions to be revoked

   * @return A {@link AccessControlProtos} RevokeRequest

   */

  public static AccessControlProtos.RevokeRequest buildRevokeRequest(

      String username, TableName tableName, byte[] family, byte[] qualifier,

      AccessControlProtos.Permission.Action... actions) {

    AccessControlProtos.Permission.Builder ret =

        AccessControlProtos.Permission.newBuilder();

    AccessControlProtos.TablePermission.Builder permissionBuilder =

        AccessControlProtos.TablePermission.newBuilder();

    for (AccessControlProtos.Permission.Action a : actions) {

      permissionBuilder.addAction(a);

    }

    if (tableName != null) {

      permissionBuilder.setTableName(ProtobufUtil.toProtoTableName(tableName));

    }

    if (family != null) {

      permissionBuilder.setFamily(HBaseZeroCopyByteString.wrap(family));

    }

    if (qualifier != null) {

      permissionBuilder.setQualifier(HBaseZeroCopyByteString.wrap(qualifier));

    }

    ret.setType(AccessControlProtos.Permission.Type.Table)

       .setTablePermission(permissionBuilder);

    return AccessControlProtos.RevokeRequest.newBuilder()

      .setUserPermission(

          AccessControlProtos.UserPermission.newBuilder()

              .setUser(ByteString.copyFromUtf8(username))

              .setPermission(ret)

      ).build();

  }

  /**

   * Create a request to revoke user permissions.

   *

   * @param username the short user name whose permissions to be revoked

   * @param namespace optional table name the permissions apply

   * @param actions the permissions to be revoked

   * @return A {@link AccessControlProtos} RevokeRequest

   */

  public static AccessControlProtos.RevokeRequest buildRevokeRequest(

      String username, String namespace,

      AccessControlProtos.Permission.Action... actions) {

    AccessControlProtos.Permission.Builder ret =

        AccessControlProtos.Permission.newBuilder();

    AccessControlProtos.NamespacePermission.Builder permissionBuilder =

        AccessControlProtos.NamespacePermission.newBuilder();

    for (AccessControlProtos.Permission.Action a : actions) {

      permissionBuilder.addAction(a);

    }

    if (namespace != null) {

      permissionBuilder.setNamespaceName(ByteString.copyFromUtf8(namespace));