Java tutorial
/* * Licensed 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. */ /* * Licensed 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.wizecommerce.hecuba.astyanax; import java.nio.ByteBuffer; import java.util.*; import org.apache.commons.collections.CollectionUtils; import org.apache.commons.collections.MapUtils; import org.apache.commons.configuration.Configuration; import org.apache.commons.lang.StringUtils; import org.apache.commons.lang.exception.ExceptionUtils; import com.google.common.base.Joiner; import com.netflix.astyanax.*; import com.netflix.astyanax.clock.ClockType; import com.netflix.astyanax.connectionpool.Host; import com.netflix.astyanax.connectionpool.HostStats; import com.netflix.astyanax.connectionpool.NodeDiscoveryType; import com.netflix.astyanax.connectionpool.OperationResult; import com.netflix.astyanax.connectionpool.exceptions.ConnectionException; import com.netflix.astyanax.connectionpool.impl.*; import com.netflix.astyanax.impl.AstyanaxConfigurationImpl; import com.netflix.astyanax.model.*; import com.netflix.astyanax.query.ColumnQuery; import com.netflix.astyanax.query.PreparedIndexExpression; import com.netflix.astyanax.query.RowQuery; import com.netflix.astyanax.serializers.StringSerializer; import com.netflix.astyanax.thrift.ThriftFamilyFactory; import com.wizecommerce.hecuba.*; import com.wizecommerce.hecuba.util.ClientManagerUtils; import com.wizecommerce.hecuba.util.ConfigUtils; /** * @author Eran Chinthaka Withana */ public class AstyanaxBasedHecubaClientManager<K> extends HecubaClientManager<K> { Keyspace keyspace; ColumnFamily<K, String> columnFamily; ColumnFamily<String, K> secondaryIndexColumnFamily; AstyanaxConfigurationImpl astyanaxConfigurationImpl; ConnectionPoolConfigurationImpl connectionPoolConfigurationImpl; CountingConnectionPoolMonitor connectionPoolMonitor; AstyanaxContext<Keyspace> context; AstyanaxContext<Cluster> clusterContext; Serializer<K> keySerializer; private Clock clock = ClockType.ASYNC_MICRO.get(); public AstyanaxBasedHecubaClientManager() { } public AstyanaxBasedHecubaClientManager(CassandraParamsBean parameters, Serializer<K> keySerializer) { super(parameters); initialize(getClusterName(), getLocationURL(), getPort(), getKeyspace()); this.columnFamily = new ColumnFamily<K, String>(getColumnFamilyName(), keySerializer, StringSerializer.get()); this.keySerializer = keySerializer; if (columnsToIndexOnColumnNameAndValue != null && columnsToIndexOnColumnNameAndValue.size() > 0) { String secondaryIndexedColumnFamily = ConfigUtils.getInstance().getConfiguration().getString( HecubaConstants.GLOBAL_PROP_NAME_PREFIX + "." + columnFamily + ".secondaryIndexCF", columnFamily.getName() + HecubaConstants.SECONDARY_INDEX_CF_NAME_SUFFIX); this.secondaryIndexColumnFamily = new ColumnFamily<String, K>(secondaryIndexedColumnFamily, StringSerializer.get(), keySerializer); } } public void initialize(String clusterName, String locationUrls, String port, String keyspaceName) { astyanaxConfigurationImpl = new AstyanaxConfigurationImpl(); final Configuration configuration = ConfigUtils.getInstance().getConfiguration(); astyanaxConfigurationImpl.setDiscoveryType(NodeDiscoveryType .valueOf(configuration.getString(HecubaConstants.ASTYANAX_NODE_DISCOVERY_TYPE, "RING_DESCRIBE"))); astyanaxConfigurationImpl.setConnectionPoolType(ConnectionPoolType .valueOf(configuration.getString(HecubaConstants.ASTYANAX_CONNECTION_POOL_TYPE, "TOKEN_AWARE"))); connectionPoolConfigurationImpl = new ConnectionPoolConfigurationImpl("MyConnectionPool") .setPort(Integer.parseInt(port)).setSeeds(getListOfNodesAndPorts(locationUrls, port)) .setMaxConnsPerHost(configuration.getInteger(HecubaConstants.ASTYANAX_MAX_CONNS_PER_HOST, 3)); // Will resort hosts per token partition every 10 seconds SmaLatencyScoreStrategyImpl smaLatencyScoreStrategyImpl = new SmaLatencyScoreStrategyImpl( configuration.getInteger(HecubaConstants.ASTYANAX_LATENCY_AWARE_UPDATE_INTERVAL, 10000), configuration.getInteger(HecubaConstants.ASTYANAX_LATENCY_AWARE_RESET_INTERVAL, 10000), configuration.getInteger(HecubaConstants.ASTYANAX_LATENCY_AWARE_WINDOW_SIZE, 100), configuration.getFloat(HecubaConstants.ASTYANAX_LATENCY_AWARE_BADNESS_INTERVAL, 0.5f)); // Enabled SMA. Omit this to use round robin with a token range. connectionPoolConfigurationImpl.setLatencyScoreStrategy(smaLatencyScoreStrategyImpl); if (StringUtils.isNotBlank(username) && StringUtils.isNotBlank(password)) { SimpleAuthenticationCredentials simpleAuth = new SimpleAuthenticationCredentials(username, password); connectionPoolConfigurationImpl.setAuthenticationCredentials(simpleAuth); } connectionPoolMonitor = new CountingConnectionPoolMonitor(); context = new AstyanaxContext.Builder().forCluster(clusterName).forKeyspace(keyspaceName) .withAstyanaxConfiguration(astyanaxConfigurationImpl) .withConnectionPoolConfiguration(connectionPoolConfigurationImpl) .withConnectionPoolMonitor(connectionPoolMonitor).buildKeyspace(ThriftFamilyFactory.getInstance()); context.start(); keyspace = context.getEntity(); if (clusterContext == null) { initiateClusterContext(clusterName); } } @Override public void updateString(K key, String columnName, String value, long timestamp, int ttl) { MutationBatch m = keyspace.prepareMutationBatch(); // set the timestamp, if set. if (timestamp > 0) { m.setTimestamp(timestamp); } updateSecondaryIndexes(key, columnName, value, ttl, m); m.withRow(columnFamily, key).putColumn(columnName, value, ttl > 0 ? ttl : null); try { m.execute(); } catch (ConnectionException e) { log.error(ExceptionUtils.getStackTrace(e)); } } private void updateSecondaryIndexes(K key, String columnName, String value, int ttl, MutationBatch mutationBatch) { // first check whether we have secondary indexes enabled for this CF and the given column has a secondary // index on it. if (isSecondaryIndexByColumnNameAndValueEnabledForColumn(columnName)) { // first retrieve the old value of this column to delete it from the secondary index. final String oldValue = readString(key, columnName); updateSecondaryIndexColumnFamily(key, columnName, value, ttl, mutationBatch, oldValue); } if (isSecondaryIndexByColumnNameEnabledForColumn(columnName)) { updateSecondaryIndexColumnFamily(key, columnName, "", ttl, mutationBatch, ""); } } private void updateSecondaryIndexColumnFamily(K key, String columnName, String value, int ttl, MutationBatch mutationBatch, String oldValue) { // enqueue a deletion to the secondary index to remove the previous value of this column. if (!StringUtils.isBlank(oldValue) && !"null".equalsIgnoreCase(oldValue)) { mutationBatch.withRow(secondaryIndexColumnFamily, getSecondaryIndexKey(columnName, oldValue)) .deleteColumn(key); } // add the new value to the secondary index CF. Make sure to handle the TTLs properly. mutationBatch.withRow(secondaryIndexColumnFamily, getSecondaryIndexKey(columnName, value)).putColumn(key, key, keySerializer, ttl > 0 ? ttl : null); } @Override public void updateByteBuffer(K key, String columnName, ByteBuffer value) { try { MutationBatch m = keyspace.prepareMutationBatch(); m.withRow(columnFamily, key).putColumn(columnName, value, null); m.execute(); } catch (ConnectionException e) { log.warn("Couldn't update byte buffer ", e); } } public AstyanaxContext<Cluster> initiateClusterContext(String clusterName) { clusterContext = new AstyanaxContext.Builder().forCluster(clusterName) .withAstyanaxConfiguration(new AstyanaxConfigurationImpl()) .withConnectionPoolConfiguration(new ConnectionPoolConfigurationImpl(clusterName) .setMaxConnsPerHost(1).setSeeds(getListOfNodesAndPorts(locationURLs, ports)) .setPort(Integer.parseInt(ports))) .withConnectionPoolMonitor(new CountingConnectionPoolMonitor()) .buildCluster(ThriftFamilyFactory.getInstance()); clusterContext.start(); return clusterContext; } @Override public void updateRow(K key, Map<String, Object> row, Map<String, Long> timestamps, Map<String, Integer> ttls) throws Exception { // Inserting data MutationBatch m = keyspace.prepareMutationBatch(); MutationBatch secondaryIndexMutation = keyspace.prepareMutationBatch(); ColumnListMutation<String> columnListMutation = m.withRow(columnFamily, key); // check whether we have to set the timestamps. final boolean timestampsDefined = timestamps != null; for (String columnName : row.keySet()) { final Object value = row.get(columnName); // we will set the ttls if defined, if we pass that as null so that internally it will NOT set the ttls. final Integer ttl = ttls == null ? null : ttls.get(columnName); String valueToInsert = ClientManagerUtils.getInstance().convertValueForStorage(value); // if timestamps are set, pass that on to the columnListMutation. The tricky thing here is once you set // a timestamp that will be used from that point beyond. So if a timestamp is NOT defined at least for one // column name then we need to set that timestamp to proper system timestamp. if (timestampsDefined) { columnListMutation.setTimestamp(timestamps.get(columnName) == null || timestamps.get(columnName) < 1 ? clock.getCurrentTime() : timestamps.get(columnName)); } columnListMutation.putColumn(columnName, valueToInsert, ttl); updateSecondaryIndexes(key, columnName, valueToInsert, ttl == null ? -1 : ttl, secondaryIndexMutation); } try { // first update secondary indexes. if (!secondaryIndexMutation.isEmpty()) { final OperationResult<Void> secondaryIndexMutationExecResult = secondaryIndexMutation.execute(); log.debug("Row Inserted into Cassandra secondary indexes. Exec Time = " + secondaryIndexMutationExecResult.getLatency() + ", " + "Host used = " + secondaryIndexMutationExecResult.getHost().getHostName()); } OperationResult<Void> result = m.execute(); log.debug("Row Inserted into Cassandra. Exec Time = " + result.getLatency() + ", Host used = " + result.getHost().getHostName()); } catch (ConnectionException e) { if (log.isDebugEnabled()) { log.debug("HecubaClientManager error while updating key " + key.toString()); } throw e; } } @Override public String readString(K key, String columnName) { Column<String> columnByName = readColumn(key, columnName); return columnByName == null ? null : columnByName.getStringValue(); } private Column<String> readColumn(K key, String columnName) { try { OperationResult<ColumnList<String>> result = keyspace.prepareQuery(columnFamily).getKey(key).execute(); return result.getResult().getColumnByName(columnName); } catch (ConnectionException e) { if (log.isDebugEnabled()) { log.debug("HecubaClientManager error while reading key " + key.toString() + ". " + ExceptionUtils.getStackTrace(e)); } } return null; } @Override public CassandraColumn readColumnInfo(K key, String columnName) { Column<String> columnByName = readColumn(key, columnName); return columnByName == null ? null : new CassandraColumn(columnByName.getName(), columnByName.getStringValue(), columnByName.getTimestamp(), columnByName.getTtl()); } public CassandraResultSet<K, String> readAllColumns(K key) throws ConnectionException { try { OperationResult<ColumnList<String>> result = keyspace.prepareQuery(columnFamily).getKey(key).execute(); ColumnList<String> columns = result.getResult(); if (isClientAdapterDebugMessagesEnabled) { log.info("Row retrieved from Cassandra. Exec Time (micro-sec) = " + result.getLatency() / 1000 + ", Host used = " + result.getHost() + ", Key = " + key); } return new AstyanaxResultSet<>(columns); } catch (ConnectionException e) { if (log.isDebugEnabled()) { log.debug("HecubaClientManager error while reading key " + key.toString()); } throw e; } } @Override public CassandraResultSet<K, String> readColumnSlice(K key, String start, String end, boolean reversed, int count) { try { final OperationResult<ColumnList<String>> executeResult = keyspace.prepareQuery(columnFamily) .getKey(key).withColumnRange(start, end, reversed, count).execute(); if (executeResult != null) { return new AstyanaxResultSet<K, String>(executeResult.getResult()); } } catch (ConnectionException e) { log.warn("Couldn't execute column slice query ", e); } return null; } @Override public CassandraResultSet readAllColumnsBySecondaryIndex(Map<String, String> parameters, int limit) { List<PreparedIndexExpression<K, String>> clauses = new ArrayList<PreparedIndexExpression<K, String>>(); for (Map.Entry<String, String> entry : parameters.entrySet()) { PreparedIndexExpression<K, String> clause = columnFamily.newIndexClause().whereColumn(entry.getKey()) .equals().value(entry.getValue()); clauses.add(clause); } OperationResult<Rows<K, String>> result; try { result = keyspace.prepareQuery(columnFamily).searchWithIndex() // .setStartKey(0L) .addPreparedExpressions(clauses).execute(); Rows<K, String> rowItems = result.getResult(); if (rowItems.size() > 0) { Row<K, String> row = rowItems.getRowByIndex(0); AstyanaxResultSet<K, String> resultSet = new AstyanaxResultSet<K, String>(row.getColumns()); return resultSet; } } catch (ConnectionException e) { log.warn("HecubaClientManager error while reading secondary index key " + parameters.toString()); if (log.isDebugEnabled()) { log.debug("Caught Exception", e); } } return null; } @Override public Long getCounterValue(K key, String counterColumnName) { try { RowQuery<K, String> row = keyspace.prepareQuery(columnFamily).getKey(key); if (row != null) { ColumnQuery<String> column = row.getColumn(counterColumnName); if (column != null) { OperationResult<Column<String>> executeResult = column.execute(); if (executeResult != null) { Column<String> result = executeResult.getResult(); return result != null ? result.getLongValue() : 0L; } else { return 0L; } } else { return 0L; } } else { return 0L; } } catch (ConnectionException e) { if (log.isDebugEnabled()) { log.debug("HecubaClientManager error while reading key " + key.toString() + ". " + ExceptionUtils.getStackTrace(e)); log.debug("Caught Exception", e); } } return 0L; } @Override public void updateCounter(K key, String counterColumnName, long value) { try { keyspace.prepareColumnMutation(columnFamily, key, counterColumnName).incrementCounterColumn(value) .execute(); } catch (ConnectionException e) { log.error(ExceptionUtils.getStackTrace(e)); } } @Override public void incrementCounter(K key, String counterColumnName) { this.updateCounter(key, counterColumnName, 1); } @Override public void decrementCounter(K key, String counterColumnName) { this.updateCounter(key, counterColumnName, -1); } @Override public void deleteColumn(K key, String columnName) { MutationBatch m = keyspace.prepareMutationBatch(); // first check whether this is a column we have a seconday index on. if (isSecondaryIndexByColumnNameAndValueEnabledForColumn(columnName)) { final Column<String> oldColumn = readColumn(key, columnName); if (oldColumn != null) { m.withRow(secondaryIndexColumnFamily, getSecondaryIndexKey(columnName, oldColumn.getStringValue())) .deleteColumn(key); } } if (isSecondaryIndexByColumnNameEnabledForColumn(columnName)) { m.withRow(secondaryIndexColumnFamily, getSecondaryIndexKey(columnName, "")).deleteColumn(key); } // delete the column from the main CF m.withRow(columnFamily, key).deleteColumn(columnName); try { m.execute(); } catch (ConnectionException e) { log.error(ExceptionUtils.getStackTrace(e)); } } @Override public void deleteRow(K key, long timestamp) { try { MutationBatch m = keyspace.prepareMutationBatch(); timestamp = timestamp > 0 ? timestamp : keyspace.getConfig().getClock().getCurrentTime(); // first delete all the secondary indexes. if (isSecondaryIndexByColumnNameAndValueEnabled || isSecondaryIndexesByColumnNamesEnabled) { // first read the old values of columns. final CassandraResultSet<K, String> oldValues = readColumns(key, columnsToIndexOnColumnNameAndValue); if (isSecondaryIndexByColumnNameAndValueEnabled) { for (String columnName : columnsToIndexOnColumnNameAndValue) { m.withRow(secondaryIndexColumnFamily, getSecondaryIndexKey(columnName, oldValues.getString(columnName))) .setTimestamp(timestamp).deleteColumn(key); } } if (isSecondaryIndexesByColumnNamesEnabled) { for (String columnName : oldValues.getColumnNames()) { if (columnName.matches(secondaryIdxByColumnPattern)) { m.withRow(secondaryIndexColumnFamily, getSecondaryIndexKey(columnName, "")) .setTimestamp(timestamp).deleteColumn(key); } } } } // now delete the main row. m.withRow(columnFamily, key).setTimestamp(timestamp).delete(); m.execute(); } catch (ConnectionException e) { log.error(ExceptionUtils.getStackTrace(e)); } catch (Exception e) { log.error(ExceptionUtils.getStackTrace(e)); } } @Override public CassandraResultSet<K, String> retrieveBySecondaryIndex(String columnName, String columnValue) { if (isSecondaryIndexByColumnNameAndValueEnabledForColumn(columnName)) { return retrieveFromSecondaryIndex(columnName, columnValue); } return null; } @Override public CassandraResultSet<K, String> retrieveBySecondaryIndex(String columnName, List<String> columnValues) { if (isSecondaryIndexByColumnNameAndValueEnabledForColumn(columnName)) { return retrieveFromSecondaryIndex(columnName, columnValues); } return null; } private CassandraResultSet<K, String> retrieveFromSecondaryIndex(String columnName, String columnValue) { try { List<K> mappingObjectIds = retrieveKeysFromSecondaryIndex(columnName, columnValue); if (CollectionUtils.isNotEmpty(mappingObjectIds)) { return readAllColumns(new HashSet<K>(mappingObjectIds)); } } catch (Exception e) { log.warn("Error executing retrieveBySecondaryIndex ", e); } return null; } private CassandraResultSet<K, String> retrieveFromSecondaryIndex(String columnName, List<String> columnValues) { try { Map<String, List<K>> keysMap = retrieveKeysFromSecondaryIndex(columnName, columnValues); if (MapUtils.isNotEmpty(keysMap)) { Set<K> keys = new HashSet<>(); for (List<K> keysForColValue : keysMap.values()) { keys.addAll(keysForColValue); } return readAllColumns(keys); } } catch (Exception e) { log.warn("Error executing retrieveBySecondaryIndex for multiple column values", e); } return null; } @Override public CassandraResultSet<K, String> retrieveByColumnNameBasedSecondaryIndex(String columnName) { if (isSecondaryIndexByColumnNameEnabledForColumn(columnName)) { return retrieveFromSecondaryIndex(columnName, ""); } return null; } @Override public CassandraResultSet<K, String> readColumns(K key, List<String> columnName) throws Exception { final OperationResult<ColumnList<String>> operationResult = keyspace.prepareQuery(columnFamily).getKey(key) .withColumnSlice(columnName).execute(); if (operationResult != null) { return new AstyanaxResultSet<K, String>(operationResult.getResult()); } return null; } @Override public CassandraResultSet<K, String> readColumns(Set<K> keys, List<String> columnNames) throws Exception { if (CollectionUtils.isNotEmpty(columnNames)) { final OperationResult<Rows<K, String>> result = keyspace.prepareQuery(columnFamily).getKeySlice(keys) .withColumnSlice(columnNames).execute(); if (isClientAdapterDebugMessagesEnabled) { log.info(columnNames.size() + " columns retrieved from Cassandra [Astyanax] for " + keys.size() + " keys . Exec Time (micro-sec) = " + (result.getLatency() / 1000) + ", Host used = " + result.getHost()); } return new AstyanaxResultSet<K, String>(result); } else { return readAllColumns(keys); } } @Override public CassandraResultSet<K, String> readAllColumns(Set<K> keys) throws Exception { // This method was added as part of multi-get feature for cache calls. try { OperationResult<Rows<K, String>> result = keyspace.prepareQuery(columnFamily).getKeySlice(keys) .execute(); if (isClientAdapterDebugMessagesEnabled) { log.info("Rows retrieved from Cassandra [Astyanax] (for " + keys.size() + " keys). Exec Time " + "(micro-sec) = " + result.getLatency() / 1000 + ", Host used = " + result.getHost()); } return new AstyanaxResultSet<K, String>(result); } catch (ConnectionException e) { log.warn("HecubaClientManager [Astyanax] error while reading multiple keys. Number of keys = " + keys.size() + ", keys = " + keys.toString()); if (log.isDebugEnabled()) { log.debug("Caught Exception while reading for multiple keys", e); logDownedHosts(); } throw e; } } @Override public CassandraResultSet<K, String> readColumnSlice(Set<K> keys, String start, String end, boolean reversed) { try { final OperationResult<Rows<K, String>> rowSliceQueryResult = keyspace.prepareQuery(columnFamily) .getKeySlice(keys).withColumnRange(start, end, reversed, Integer.MAX_VALUE).execute(); return new AstyanaxResultSet<K, String>(rowSliceQueryResult); } catch (ConnectionException e) { log.warn("error while executing a row slice query ", e); if (log.isDebugEnabled()) { logDownedHosts(); } } return null; } @Override public void deleteColumns(K key, List<String> columnNameList) { for (String columnName : columnNameList) { deleteColumn(key, columnName); } } @Override public List<K> retrieveKeysBySecondaryIndex(String columnName, String columnValue) { if (isSecondaryIndexByColumnNameAndValueEnabledForColumn(columnName)) { return retrieveKeysFromSecondaryIndex(columnName, columnValue); } return null; } @Override public Map<String, List<K>> retrieveKeysBySecondaryIndex(String columnName, List<String> columnValues) { if (isSecondaryIndexByColumnNameAndValueEnabledForColumn(columnName)) { return retrieveKeysFromSecondaryIndex(columnName, columnValues); } return null; } @Override public List<K> retrieveKeysByColumnNameBasedSecondaryIndex(String columnName) { if (isSecondaryIndexByColumnNameEnabledForColumn(columnName)) { return retrieveKeysFromSecondaryIndex(columnName, ""); } return null; } private List<K> retrieveKeysFromSecondaryIndex(String columnName, String columnValue) { try { String secondaryIndexKey = getSecondaryIndexKey(columnName, columnValue); final OperationResult<ColumnList<K>> result = keyspace.prepareQuery(secondaryIndexColumnFamily) .getKey(secondaryIndexKey).execute(); if (isClientAdapterDebugMessagesEnabled) { log.debug("Secondary Index Row for " + secondaryIndexKey + " retrieved from Cassandra. Exec Time = " + result.getLatency() + ", Host used = " + result.getHost().getHostName()); } if (result != null && result.getResult().size() > 0) { final Iterator<Column<K>> iterator = result.getResult().iterator(); List<K> rowKeys = new ArrayList<K>(); while (iterator.hasNext()) { rowKeys.add(iterator.next().getName()); } return rowKeys; } } catch (Exception e) { log.warn("Error executing retrieveKeysFromSecondaryIndex ", e); if (log.isDebugEnabled()) { logDownedHosts(); } } return null; } private Map<String, List<K>> retrieveKeysFromSecondaryIndex(String columnName, List<String> columnValues) { try { List<String> secondaryIndexKeys = getSecondaryIndexKeys(columnName, columnValues); OperationResult<Rows<String, K>> result = keyspace.prepareQuery(secondaryIndexColumnFamily) .getKeySlice(secondaryIndexKeys).execute(); if (isClientAdapterDebugMessagesEnabled) { log.debug("Secondary Index Row for " + Joiner.on(",").join(secondaryIndexKeys) + " retrieved from Cassandra. Exec Time = " + result.getLatency() + ", Host used = " + result.getHost().getHostName()); } if (result != null && result.getResult().size() > 0) { Map<String, List<K>> rowKeysMap = new HashMap<>(); Iterator<Row<String, K>> rowIterator = result.getResult().iterator(); while (rowIterator.hasNext()) { Row<String, K> row = rowIterator.next(); Iterator<Column<K>> columnIterator = row.getColumns().iterator(); List<K> keys = new ArrayList<>(); while (columnIterator.hasNext()) { keys.add(columnIterator.next().getName()); } if (CollectionUtils.isNotEmpty(keys)) { rowKeysMap.put(getSecondaryIndexedColumnValue(row.getKey()), keys); } } return rowKeysMap; } } catch (Exception e) { log.warn("Error executing retrieveKeysFromSecondaryIndex for multiple column values", e); if (log.isDebugEnabled()) { logDownedHosts(); } } return null; } @Override protected void logDownedHosts() { Map<Host, HostStats> hostStatsMap = connectionPoolMonitor.getHostStats(); StringBuilder allHostsSB = new StringBuilder("All Hosts = {"); StringBuilder downedHostsSB = new StringBuilder("Downed Hosts = {"); for (Host host : hostStatsMap.keySet()) { allHostsSB.append(host.getHostName() + ", "); HostStats stats = hostStatsMap.get(host); if (stats != null && !stats.isUp()) { downedHostsSB.append(host.getHostName() + ", "); } } if (allHostsSB.toString().endsWith(", ")) { allHostsSB.setLength(allHostsSB.length() - 2); } allHostsSB.append("}"); log.debug(allHostsSB.toString()); if (downedHostsSB.toString().endsWith(", ")) { downedHostsSB.setLength(downedHostsSB.length() - 2); } downedHostsSB.append("}"); log.debug(downedHostsSB.toString()); } }