/*
* 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.facebook.presto.connector.jmx;
import com.google.common.collect.EvictingQueue;
import com.google.common.collect.ImmutableList;
import javax.inject.Inject;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import static com.google.common.base.Preconditions.checkArgument;
import static java.util.stream.Collectors.toSet;
public class JmxHistoricalData
{
private final Set<String> tables;
private final Map<String, EvictingQueue<List<Object>>> tableData = new HashMap<>();
@Inject
public JmxHistoricalData(JmxConnectorConfig jmxConfig)
{
this(jmxConfig.getMaxEntries(), jmxConfig.getDumpTables());
}
public JmxHistoricalData(int maxEntries, Set<String> tableNames)
{
tables = tableNames.stream().map(String::toLowerCase).collect(toSet());
for (String tableName : tables) {
tableData.put(tableName, EvictingQueue.create(maxEntries));
}
}
public Set<String> getTables()
{
return tables;
}
public synchronized void addRow(String tableName, List<Object> row)
{
String lowerCaseTableName = tableName.toLowerCase();
checkArgument(tableData.containsKey(lowerCaseTableName));
tableData.get(lowerCaseTableName).add(row);
}
public synchronized List<List<Object>> getRows(String tableName, List<Integer> selectedColumns)
{
String lowerCaseTableName = tableName.toLowerCase();
if (!tableData.containsKey(lowerCaseTableName)) {
return ImmutableList.of();
}
return projectRows(tableData.get(lowerCaseTableName), selectedColumns);
}
private List<List<Object>> projectRows(Collection<List<Object>> rows, List<Integer> selectedColumns)
{
ImmutableList.Builder<List<Object>> result = ImmutableList.builder();
for (List<Object> row : rows) {
ImmutableList.Builder<Object> projectedRow = ImmutableList.builder();
for (Integer selectedColumn : selectedColumns) {
projectedRow.add(row.get(selectedColumn));
}
result.add(projectedRow.build());
}
return result.build();
}
}