/*
* Copyright © 2015 Cask Data, Inc.
*
* 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 co.cask.cdap.data2.datafabric.dataset;
import co.cask.cdap.api.dataset.Dataset;
import co.cask.cdap.api.dataset.DatasetProperties;
import co.cask.cdap.proto.Id;
import java.util.Map;
import javax.annotation.Nullable;
/**
* Provides {@link Dataset} instances.
*/
public interface DatasetProvider {
/**
* Gets a dataset.
*
* @param instance the dataset ID
* @param classLoader the classloader to use
* @param arguments the runtime arguments for the dataset
* @param <T> the type of dataset
* @return the dataset
*/
<T extends Dataset> T get(
Id.DatasetInstance instance,
@Nullable ClassLoader classLoader,
@Nullable Map<String, String> arguments) throws Exception;
/**
* Gets a dataset, and creates it first if it doesn't yet exist.
*
* @param instance the dataset ID
* @param type the type of dataset
* @param creationProps the creation properties
* @param classLoader the classloader to use
* @param arguments the runtime arguments for the dataset
* @param <T> the type of dataset
* @return the dataset
*/
<T extends Dataset> T getOrCreate(
Id.DatasetInstance instance,
String type,
DatasetProperties creationProps,
@Nullable ClassLoader classLoader,
@Nullable Map<String, String> arguments) throws Exception;
}