/*
* Copyright 2014 Red Hat, Inc. and/or its affiliates.
*
* 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 org.dashbuilder.dataset.engine.index.stats;
import org.dashbuilder.dataset.engine.index.DataSetIndexElement;
/**
* A DataSetIndex stats
*/
public interface DataSetIndexStats {
/**
* Time required to "build" (load, create, filter, ...) the data set.
* @return Time in nanoseconds
*/
long getBuildTime();
/**
* The real usage time this element would have if was not indexed.
* @return Time in nanoseconds
*/
long getReuseTime();
/**
* The ratio between the reuse time and the build time.
*/
double getReuseRate();
/**
* Total number of group operations over the data set
*/
int getNumberOfGroupOps();
/**
* Total number of filter operations executed over the data set
*/
int getNumberOfFilterOps();
/**
* Total number of sort operations executed over the data set
*/
int getNumberOfSortOps();
/**
* Total number of aggregate function calculations executed over the data set
*/
int getNumberOfAggFunctions();
/**
* An index reference to the element that takes more time to get instantiated.
*/
DataSetIndexElement getLongestBuild();
/**
* An index reference to the element that takes less time to get instantiated.
*/
DataSetIndexElement getShortestBuild();
/**
* An index reference to the less reused element.
*/
DataSetIndexElement getLessReused();
/**
* An index reference to the most reused element.
*/
DataSetIndexElement getMostReused();
/**
* Return the estimated memory (in bytes) the data set index is consuming.
* @return The number of bytes
*/
long getIndexSize();
/**
* Prints a stats summary.
* @param sep The separator string to insert between every stat.
*/
String toString(String sep);
}