server/src/com/cloud/storage/dao/SnapshotDaoImpl.java - cloudstack - Git at Google

 // 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 com.cloud.storage.dao;

 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.util.List;

 import javax.annotation.PostConstruct;
 import javax.ejb.Local;
 import javax.inject.Inject;

 import org.apache.log4j.Logger;
 import org.springframework.stereotype.Component;

 import com.cloud.server.ResourceTag.TaggedResourceType;
 import com.cloud.storage.Snapshot;
 import com.cloud.storage.Snapshot.Event;
 import com.cloud.storage.Snapshot.State;
 import com.cloud.storage.Snapshot.Type;
 import com.cloud.storage.SnapshotVO;
 import com.cloud.storage.Volume;
 import com.cloud.storage.VolumeVO;
 import com.cloud.tags.dao.ResourceTagDao;
 import com.cloud.tags.dao.ResourceTagsDaoImpl;

 import com.cloud.utils.db.*;
 import com.cloud.utils.db.JoinBuilder.JoinType;
 import com.cloud.utils.db.SearchCriteria.Func;
 import com.cloud.vm.VMInstanceVO;
 import com.cloud.vm.dao.VMInstanceDao;
 import com.cloud.vm.dao.VMInstanceDaoImpl;

 @Component
 @Local (value={SnapshotDao.class})
 public class SnapshotDaoImpl extends GenericDaoBase<SnapshotVO, Long> implements SnapshotDao {
     public static final Logger s_logger = Logger.getLogger(SnapshotDaoImpl.class.getName());
     private static final String GET_LAST_SNAPSHOT = "SELECT id FROM snapshots where volume_id = ? AND id != ? AND path IS NOT NULL ORDER BY created DESC";
     private static final String UPDATE_SNAPSHOT_VERSION = "UPDATE snapshots SET version = ? WHERE volume_id = ? AND version = ?";
     private static final String GET_SECHOST_ID = "SELECT sechost_id FROM snapshots where volume_id = ? AND backup_snap_id IS NOT NULL AND sechost_id IS NOT NULL LIMIT 1";
     private static final String UPDATE_SECHOST_ID = "UPDATE snapshots SET sechost_id = ? WHERE data_center_id = ?";

     private SearchBuilder<SnapshotVO> VolumeIdSearch;
     private SearchBuilder<SnapshotVO> VolumeIdTypeSearch;
     private SearchBuilder<SnapshotVO> ParentIdSearch;
     private SearchBuilder<SnapshotVO> backupUuidSearch;
     private SearchBuilder<SnapshotVO> VolumeIdVersionSearch;
     private SearchBuilder<SnapshotVO> HostIdSearch;
     private SearchBuilder<SnapshotVO> AccountIdSearch;
     private SearchBuilder<SnapshotVO> InstanceIdSearch;
     private SearchBuilder<SnapshotVO> StatusSearch;
     private GenericSearchBuilder<SnapshotVO, Long> CountSnapshotsByAccount;
     @Inject ResourceTagDao _tagsDao;

     @Inject protected VMInstanceDao _instanceDao;
     @Inject protected VolumeDao _volumeDao;

     @Override
     public SnapshotVO findNextSnapshot(long snapshotId) {
         SearchCriteria<SnapshotVO> sc = ParentIdSearch.create();
         sc.setParameters("prevSnapshotId", snapshotId);
         return findOneIncludingRemovedBy(sc);
     }

     @Override
      public List<SnapshotVO> listByBackupUuid(long volumeId, String backupUuid) {
         SearchCriteria<SnapshotVO> sc = backupUuidSearch.create();
         sc.setParameters("backupUuid", backupUuid);
         return listBy(sc, null);
     }

     @Override
     public List<SnapshotVO> listByVolumeIdType(long volumeId, Type type ) {
         return listByVolumeIdType(null, volumeId, type);
     }


     @Override
     public List<SnapshotVO> listByVolumeIdVersion(long volumeId, String version ) {
         return listByVolumeIdVersion(null, volumeId, version);
     }

     @Override
     public List<SnapshotVO> listByVolumeId(long volumeId) {
         return listByVolumeId(null, volumeId);
     }

     @Override
     public List<SnapshotVO> listByVolumeId(Filter filter, long volumeId ) {
         SearchCriteria<SnapshotVO> sc = VolumeIdSearch.create();
         sc.setParameters("volumeId", volumeId);
         return listBy(sc, filter);
     }

     @Override
     public List<SnapshotVO> listByHostId(long hostId) {
         return listByHostId(null, hostId);
     }

     @Override
     public List<SnapshotVO> listByHostId(Filter filter, long hostId ) {
         SearchCriteria<SnapshotVO> sc = HostIdSearch.create();
         sc.setParameters("hostId", hostId);
         sc.setParameters("status", Snapshot.State.BackedUp);
         return listBy(sc, filter);
     }

     @Override
     public List<SnapshotVO> listByVolumeIdIncludingRemoved(long volumeId) {
         SearchCriteria<SnapshotVO> sc = VolumeIdSearch.create();
         sc.setParameters("volumeId", volumeId);
         return listIncludingRemovedBy(sc, null);
     }

     public List<SnapshotVO> listByVolumeIdType(Filter filter, long volumeId, Type type ) {
         SearchCriteria<SnapshotVO> sc = VolumeIdTypeSearch.create();
         sc.setParameters("volumeId", volumeId);
         sc.setParameters("type", type.ordinal());
         return listBy(sc, filter);
     }

     public List<SnapshotVO> listByVolumeIdVersion(Filter filter, long volumeId, String version ) {
         SearchCriteria<SnapshotVO> sc = VolumeIdVersionSearch.create();
         sc.setParameters("volumeId", volumeId);
         sc.setParameters("version", version);
         return listBy(sc, filter);
     }

     public SnapshotDaoImpl() {
     }

     @PostConstruct
     protected void init() {
         VolumeIdSearch = createSearchBuilder();
         VolumeIdSearch.and("volumeId", VolumeIdSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
         VolumeIdSearch.done();

         HostIdSearch = createSearchBuilder();
         HostIdSearch.and("hostId", HostIdSearch.entity().getSecHostId(), SearchCriteria.Op.EQ);
         HostIdSearch.and("status", HostIdSearch.entity().getState(), SearchCriteria.Op.EQ);
         HostIdSearch.done();

         VolumeIdTypeSearch = createSearchBuilder();
         VolumeIdTypeSearch.and("volumeId", VolumeIdTypeSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
         VolumeIdTypeSearch.and("type", VolumeIdTypeSearch.entity().getsnapshotType(), SearchCriteria.Op.EQ);
         VolumeIdTypeSearch.done();

         VolumeIdVersionSearch = createSearchBuilder();
         VolumeIdVersionSearch.and("volumeId", VolumeIdVersionSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
         VolumeIdVersionSearch.and("version", VolumeIdVersionSearch.entity().getVersion(), SearchCriteria.Op.EQ);
         VolumeIdVersionSearch.done();

         ParentIdSearch = createSearchBuilder();
         ParentIdSearch.and("prevSnapshotId", ParentIdSearch.entity().getPrevSnapshotId(), SearchCriteria.Op.EQ);
         ParentIdSearch.done();

         backupUuidSearch = createSearchBuilder();
         backupUuidSearch.and("backupUuid", backupUuidSearch.entity().getBackupSnapshotId(), SearchCriteria.Op.EQ);
         backupUuidSearch.done();

         AccountIdSearch = createSearchBuilder();
         AccountIdSearch.and("accountId", AccountIdSearch.entity().getAccountId(), SearchCriteria.Op.EQ);
         AccountIdSearch.done();

         StatusSearch = createSearchBuilder();
         StatusSearch.and("volumeId", StatusSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
         StatusSearch.and("status", StatusSearch.entity().getState(), SearchCriteria.Op.IN);
         StatusSearch.done();

         CountSnapshotsByAccount = createSearchBuilder(Long.class);
         CountSnapshotsByAccount.select(null, Func.COUNT, null);
         CountSnapshotsByAccount.and("account", CountSnapshotsByAccount.entity().getAccountId(), SearchCriteria.Op.EQ);
         CountSnapshotsByAccount.and("removed", CountSnapshotsByAccount.entity().getRemoved(), SearchCriteria.Op.NULL);
         CountSnapshotsByAccount.done();

     	InstanceIdSearch = createSearchBuilder();
         InstanceIdSearch.and("status", InstanceIdSearch.entity().getState(), SearchCriteria.Op.IN);

     	SearchBuilder<VMInstanceVO> instanceSearch = _instanceDao.createSearchBuilder();
     	instanceSearch.and("instanceId", instanceSearch.entity().getId(), SearchCriteria.Op.EQ);

     	SearchBuilder<VolumeVO> volumeSearch = _volumeDao.createSearchBuilder();
     	volumeSearch.and("state", volumeSearch.entity().getState(), SearchCriteria.Op.EQ);
     	volumeSearch.join("instanceVolumes", instanceSearch, instanceSearch.entity().getId(), volumeSearch.entity().getInstanceId(), JoinType.INNER);

     	InstanceIdSearch.join("instanceSnapshots", volumeSearch, volumeSearch.entity().getId(), InstanceIdSearch.entity().getVolumeId(), JoinType.INNER);
     	InstanceIdSearch.done();
     }

     @Override
     public Long getSecHostId(long volumeId) {

         Transaction txn = Transaction.currentTxn();
         PreparedStatement pstmt = null;
         String sql = GET_SECHOST_ID;
         try {
             pstmt = txn.prepareAutoCloseStatement(sql);
             pstmt.setLong(1, volumeId);
             ResultSet rs = pstmt.executeQuery();
             if (rs.next()) {
                 return rs.getLong(1);
             }
         } catch (Exception ex) {
         }
         return null;
     }
     @Override
     public long getLastSnapshot(long volumeId, long snapId) {
         Transaction txn = Transaction.currentTxn();
         PreparedStatement pstmt = null;
         String sql = GET_LAST_SNAPSHOT;
         try {
             pstmt = txn.prepareAutoCloseStatement(sql);
             pstmt.setLong(1, volumeId);
             pstmt.setLong(2, snapId);
             ResultSet rs = pstmt.executeQuery();
             if (rs.next()) {
                 return rs.getLong(1);
             }
         } catch (Exception ex) {
             s_logger.error("error getting last snapshot", ex);
         }
         return 0;
     }

     @Override
     public long updateSnapshotVersion(long volumeId, String from, String to) {
         Transaction txn = Transaction.currentTxn();
         PreparedStatement pstmt = null;
         String sql = UPDATE_SNAPSHOT_VERSION;
         try {
             pstmt = txn.prepareAutoCloseStatement(sql);
             pstmt.setString(1, to);
             pstmt.setLong(2, volumeId);
             pstmt.setString(3, from);
             pstmt.executeUpdate();
             return 1;
         } catch (Exception ex) {
             s_logger.error("error getting last snapshot", ex);
         }
         return 0;
     }

     @Override
     public long updateSnapshotSecHost(long dcId, long secHostId) {
         Transaction txn = Transaction.currentTxn();
         PreparedStatement pstmt = null;
         String sql = UPDATE_SECHOST_ID;
         try {
             pstmt = txn.prepareAutoCloseStatement(sql);
             pstmt.setLong(1, secHostId);
             pstmt.setLong(2, dcId);
             pstmt.executeUpdate();
             return 1;
         } catch (Exception ex) {
             s_logger.error("error set secondary storage host id", ex);
         }
         return 0;
     }

     @Override
     public Long countSnapshotsForAccount(long accountId) {
     	SearchCriteria<Long> sc = CountSnapshotsByAccount.create();
         sc.setParameters("account", accountId);
         return customSearch(sc, null).get(0);
     }

     @Override
 	public List<SnapshotVO> listByInstanceId(long instanceId, Snapshot.State... status) {
     	SearchCriteria<SnapshotVO> sc = this.InstanceIdSearch.create();

     	if (status != null && status.length != 0) {
     	    sc.setParameters("status", (Object[])status);
     	}

     	sc.setJoinParameters("instanceSnapshots", "state", Volume.State.Ready);
     	sc.setJoinParameters("instanceVolumes", "instanceId", instanceId);
         return listBy(sc, null);
     }

     @Override
     public List<SnapshotVO> listByStatus(long volumeId, Snapshot.State... status) {
     	SearchCriteria<SnapshotVO> sc = this.StatusSearch.create();
     	sc.setParameters("volumeId", volumeId);
     	sc.setParameters("status", (Object[])status);
     	return listBy(sc, null);
     }

     @Override
     @DB
     public boolean remove(Long id) {
         Transaction txn = Transaction.currentTxn();
         txn.start();
         SnapshotVO entry = findById(id);
         if (entry != null) {
             _tagsDao.removeByIdAndType(id, TaggedResourceType.Snapshot);
         }
         boolean result = super.remove(id);
         txn.commit();
         return result;
     }

     @Override
     public List<SnapshotVO> listAllByStatus(Snapshot.State... status) {
         SearchCriteria<SnapshotVO> sc = this.StatusSearch.create();
         sc.setParameters("status", (Object[])status);
         return listBy(sc, null);
     }

     @Override
     public boolean updateState(State currentState, Event event, State nextState, SnapshotVO snapshot, Object data) {
         Transaction txn = Transaction.currentTxn();
         txn.start();
         SnapshotVO snapshotVO = (SnapshotVO)snapshot;
         snapshotVO.setState(nextState);
         super.update(snapshotVO.getId(), snapshotVO);
         txn.commit();
         return true;
     }
 }
	// 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 com.cloud.storage.dao;

	import java.sql.PreparedStatement;
	import java.sql.ResultSet;
	import java.util.List;

	import javax.annotation.PostConstruct;
	import javax.ejb.Local;
	import javax.inject.Inject;

	import org.apache.log4j.Logger;
	import org.springframework.stereotype.Component;

	import com.cloud.server.ResourceTag.TaggedResourceType;
	import com.cloud.storage.Snapshot;
	import com.cloud.storage.Snapshot.Event;
	import com.cloud.storage.Snapshot.State;
	import com.cloud.storage.Snapshot.Type;
	import com.cloud.storage.SnapshotVO;
	import com.cloud.storage.Volume;
	import com.cloud.storage.VolumeVO;
	import com.cloud.tags.dao.ResourceTagDao;
	import com.cloud.tags.dao.ResourceTagsDaoImpl;

	import com.cloud.utils.db.*;
	import com.cloud.utils.db.JoinBuilder.JoinType;
	import com.cloud.utils.db.SearchCriteria.Func;
	import com.cloud.vm.VMInstanceVO;
	import com.cloud.vm.dao.VMInstanceDao;
	import com.cloud.vm.dao.VMInstanceDaoImpl;

	@Component
	@Local (value={SnapshotDao.class})
	public class SnapshotDaoImpl extends GenericDaoBase<SnapshotVO, Long> implements SnapshotDao {
	public static final Logger s_logger = Logger.getLogger(SnapshotDaoImpl.class.getName());
	private static final String GET_LAST_SNAPSHOT = "SELECT id FROM snapshots where volume_id = ? AND id != ? AND path IS NOT NULL ORDER BY created DESC";
	private static final String UPDATE_SNAPSHOT_VERSION = "UPDATE snapshots SET version = ? WHERE volume_id = ? AND version = ?";
	private static final String GET_SECHOST_ID = "SELECT sechost_id FROM snapshots where volume_id = ? AND backup_snap_id IS NOT NULL AND sechost_id IS NOT NULL LIMIT 1";
	private static final String UPDATE_SECHOST_ID = "UPDATE snapshots SET sechost_id = ? WHERE data_center_id = ?";

	private SearchBuilder<SnapshotVO> VolumeIdSearch;
	private SearchBuilder<SnapshotVO> VolumeIdTypeSearch;
	private SearchBuilder<SnapshotVO> ParentIdSearch;
	private SearchBuilder<SnapshotVO> backupUuidSearch;
	private SearchBuilder<SnapshotVO> VolumeIdVersionSearch;
	private SearchBuilder<SnapshotVO> HostIdSearch;
	private SearchBuilder<SnapshotVO> AccountIdSearch;
	private SearchBuilder<SnapshotVO> InstanceIdSearch;
	private SearchBuilder<SnapshotVO> StatusSearch;
	private GenericSearchBuilder<SnapshotVO, Long> CountSnapshotsByAccount;
	@Inject ResourceTagDao _tagsDao;

	@Inject protected VMInstanceDao _instanceDao;
	@Inject protected VolumeDao _volumeDao;

	@Override
	public SnapshotVO findNextSnapshot(long snapshotId) {
	SearchCriteria<SnapshotVO> sc = ParentIdSearch.create();
	sc.setParameters("prevSnapshotId", snapshotId);
	return findOneIncludingRemovedBy(sc);
	}

	@Override
	public List<SnapshotVO> listByBackupUuid(long volumeId, String backupUuid) {
	SearchCriteria<SnapshotVO> sc = backupUuidSearch.create();
	sc.setParameters("backupUuid", backupUuid);
	return listBy(sc, null);
	}

	@Override
	public List<SnapshotVO> listByVolumeIdType(long volumeId, Type type ) {
	return listByVolumeIdType(null, volumeId, type);
	}


	@Override
	public List<SnapshotVO> listByVolumeIdVersion(long volumeId, String version ) {
	return listByVolumeIdVersion(null, volumeId, version);
	}

	@Override
	public List<SnapshotVO> listByVolumeId(long volumeId) {
	return listByVolumeId(null, volumeId);
	}

	@Override
	public List<SnapshotVO> listByVolumeId(Filter filter, long volumeId ) {
	SearchCriteria<SnapshotVO> sc = VolumeIdSearch.create();
	sc.setParameters("volumeId", volumeId);
	return listBy(sc, filter);
	}

	@Override
	public List<SnapshotVO> listByHostId(long hostId) {
	return listByHostId(null, hostId);
	}

	@Override
	public List<SnapshotVO> listByHostId(Filter filter, long hostId ) {
	SearchCriteria<SnapshotVO> sc = HostIdSearch.create();
	sc.setParameters("hostId", hostId);
	sc.setParameters("status", Snapshot.State.BackedUp);
	return listBy(sc, filter);
	}

	@Override
	public List<SnapshotVO> listByVolumeIdIncludingRemoved(long volumeId) {
	SearchCriteria<SnapshotVO> sc = VolumeIdSearch.create();
	sc.setParameters("volumeId", volumeId);
	return listIncludingRemovedBy(sc, null);
	}

	public List<SnapshotVO> listByVolumeIdType(Filter filter, long volumeId, Type type ) {
	SearchCriteria<SnapshotVO> sc = VolumeIdTypeSearch.create();
	sc.setParameters("volumeId", volumeId);
	sc.setParameters("type", type.ordinal());
	return listBy(sc, filter);
	}

	public List<SnapshotVO> listByVolumeIdVersion(Filter filter, long volumeId, String version ) {
	SearchCriteria<SnapshotVO> sc = VolumeIdVersionSearch.create();
	sc.setParameters("volumeId", volumeId);
	sc.setParameters("version", version);
	return listBy(sc, filter);
	}

	public SnapshotDaoImpl() {
	}

	@PostConstruct
	protected void init() {
	VolumeIdSearch = createSearchBuilder();
	VolumeIdSearch.and("volumeId", VolumeIdSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
	VolumeIdSearch.done();

	HostIdSearch = createSearchBuilder();
	HostIdSearch.and("hostId", HostIdSearch.entity().getSecHostId(), SearchCriteria.Op.EQ);
	HostIdSearch.and("status", HostIdSearch.entity().getState(), SearchCriteria.Op.EQ);
	HostIdSearch.done();

	VolumeIdTypeSearch = createSearchBuilder();
	VolumeIdTypeSearch.and("volumeId", VolumeIdTypeSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
	VolumeIdTypeSearch.and("type", VolumeIdTypeSearch.entity().getsnapshotType(), SearchCriteria.Op.EQ);
	VolumeIdTypeSearch.done();

	VolumeIdVersionSearch = createSearchBuilder();
	VolumeIdVersionSearch.and("volumeId", VolumeIdVersionSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
	VolumeIdVersionSearch.and("version", VolumeIdVersionSearch.entity().getVersion(), SearchCriteria.Op.EQ);
	VolumeIdVersionSearch.done();

	ParentIdSearch = createSearchBuilder();
	ParentIdSearch.and("prevSnapshotId", ParentIdSearch.entity().getPrevSnapshotId(), SearchCriteria.Op.EQ);
	ParentIdSearch.done();

	backupUuidSearch = createSearchBuilder();
	backupUuidSearch.and("backupUuid", backupUuidSearch.entity().getBackupSnapshotId(), SearchCriteria.Op.EQ);
	backupUuidSearch.done();

	AccountIdSearch = createSearchBuilder();
	AccountIdSearch.and("accountId", AccountIdSearch.entity().getAccountId(), SearchCriteria.Op.EQ);
	AccountIdSearch.done();

	StatusSearch = createSearchBuilder();
	StatusSearch.and("volumeId", StatusSearch.entity().getVolumeId(), SearchCriteria.Op.EQ);
	StatusSearch.and("status", StatusSearch.entity().getState(), SearchCriteria.Op.IN);
	StatusSearch.done();

	CountSnapshotsByAccount = createSearchBuilder(Long.class);
	CountSnapshotsByAccount.select(null, Func.COUNT, null);
	CountSnapshotsByAccount.and("account", CountSnapshotsByAccount.entity().getAccountId(), SearchCriteria.Op.EQ);
	CountSnapshotsByAccount.and("removed", CountSnapshotsByAccount.entity().getRemoved(), SearchCriteria.Op.NULL);
	CountSnapshotsByAccount.done();

	InstanceIdSearch = createSearchBuilder();
	InstanceIdSearch.and("status", InstanceIdSearch.entity().getState(), SearchCriteria.Op.IN);

	SearchBuilder<VMInstanceVO> instanceSearch = _instanceDao.createSearchBuilder();
	instanceSearch.and("instanceId", instanceSearch.entity().getId(), SearchCriteria.Op.EQ);

	SearchBuilder<VolumeVO> volumeSearch = _volumeDao.createSearchBuilder();
	volumeSearch.and("state", volumeSearch.entity().getState(), SearchCriteria.Op.EQ);
	volumeSearch.join("instanceVolumes", instanceSearch, instanceSearch.entity().getId(), volumeSearch.entity().getInstanceId(), JoinType.INNER);

	InstanceIdSearch.join("instanceSnapshots", volumeSearch, volumeSearch.entity().getId(), InstanceIdSearch.entity().getVolumeId(), JoinType.INNER);
	InstanceIdSearch.done();
	}

	@Override
	public Long getSecHostId(long volumeId) {

	Transaction txn = Transaction.currentTxn();
	PreparedStatement pstmt = null;
	String sql = GET_SECHOST_ID;
	try {
	pstmt = txn.prepareAutoCloseStatement(sql);
	pstmt.setLong(1, volumeId);
	ResultSet rs = pstmt.executeQuery();
	if (rs.next()) {
	return rs.getLong(1);
	}
	} catch (Exception ex) {
	}
	return null;
	}
	@Override
	public long getLastSnapshot(long volumeId, long snapId) {
	Transaction txn = Transaction.currentTxn();
	PreparedStatement pstmt = null;
	String sql = GET_LAST_SNAPSHOT;
	try {
	pstmt = txn.prepareAutoCloseStatement(sql);
	pstmt.setLong(1, volumeId);
	pstmt.setLong(2, snapId);
	ResultSet rs = pstmt.executeQuery();
	if (rs.next()) {
	return rs.getLong(1);
	}
	} catch (Exception ex) {
	s_logger.error("error getting last snapshot", ex);
	}
	return 0;
	}

	@Override
	public long updateSnapshotVersion(long volumeId, String from, String to) {
	Transaction txn = Transaction.currentTxn();
	PreparedStatement pstmt = null;
	String sql = UPDATE_SNAPSHOT_VERSION;
	try {
	pstmt = txn.prepareAutoCloseStatement(sql);
	pstmt.setString(1, to);
	pstmt.setLong(2, volumeId);
	pstmt.setString(3, from);
	pstmt.executeUpdate();
	return 1;
	} catch (Exception ex) {
	s_logger.error("error getting last snapshot", ex);
	}
	return 0;
	}

	@Override
	public long updateSnapshotSecHost(long dcId, long secHostId) {
	Transaction txn = Transaction.currentTxn();
	PreparedStatement pstmt = null;
	String sql = UPDATE_SECHOST_ID;
	try {
	pstmt = txn.prepareAutoCloseStatement(sql);
	pstmt.setLong(1, secHostId);
	pstmt.setLong(2, dcId);
	pstmt.executeUpdate();
	return 1;
	} catch (Exception ex) {
	s_logger.error("error set secondary storage host id", ex);
	}
	return 0;
	}

	@Override
	public Long countSnapshotsForAccount(long accountId) {
	SearchCriteria<Long> sc = CountSnapshotsByAccount.create();
	sc.setParameters("account", accountId);
	return customSearch(sc, null).get(0);
	}

	@Override
	public List<SnapshotVO> listByInstanceId(long instanceId, Snapshot.State... status) {
	SearchCriteria<SnapshotVO> sc = this.InstanceIdSearch.create();

	if (status != null && status.length != 0) {
	sc.setParameters("status", (Object[])status);
	}

	sc.setJoinParameters("instanceSnapshots", "state", Volume.State.Ready);
	sc.setJoinParameters("instanceVolumes", "instanceId", instanceId);
	return listBy(sc, null);
	}

	@Override
	public List<SnapshotVO> listByStatus(long volumeId, Snapshot.State... status) {
	SearchCriteria<SnapshotVO> sc = this.StatusSearch.create();
	sc.setParameters("volumeId", volumeId);
	sc.setParameters("status", (Object[])status);
	return listBy(sc, null);
	}

	@Override
	@DB
	public boolean remove(Long id) {
	Transaction txn = Transaction.currentTxn();
	txn.start();
	SnapshotVO entry = findById(id);
	if (entry != null) {
	_tagsDao.removeByIdAndType(id, TaggedResourceType.Snapshot);
	}
	boolean result = super.remove(id);
	txn.commit();
	return result;
	}

	@Override
	public List<SnapshotVO> listAllByStatus(Snapshot.State... status) {
	SearchCriteria<SnapshotVO> sc = this.StatusSearch.create();
	sc.setParameters("status", (Object[])status);
	return listBy(sc, null);
	}

	@Override
	public boolean updateState(State currentState, Event event, State nextState, SnapshotVO snapshot, Object data) {
	Transaction txn = Transaction.currentTxn();
	txn.start();
	SnapshotVO snapshotVO = (SnapshotVO)snapshot;
	snapshotVO.setState(nextState);
	super.update(snapshotVO.getId(), snapshotVO);
	txn.commit();
	return true;
	}
	}