/*
* Copyright © 2014 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.api.dataset.lib;
import co.cask.cdap.api.annotation.Beta;
import co.cask.cdap.api.common.Bytes;
import co.cask.cdap.api.dataset.DatasetAdmin;
import co.cask.cdap.api.dataset.DatasetDefinition;
import co.cask.cdap.api.dataset.DatasetProperties;
import co.cask.cdap.api.dataset.DatasetSpecification;
import co.cask.cdap.api.dataset.table.Table;
import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;
import java.io.IOException;
import java.util.Map;
/**
* DatasetDefinition for {@link IndexedTable}.
*/
@Beta
public class IndexedTableDefinition
extends AbstractDatasetDefinition<IndexedTable, DatasetAdmin> {
/**
* Configuration key for defining column names to index in the DatasetSpecification properties.
* Multiple column names should be listed as a comma-separated string, e.g. "column1,column2,etc".
*/
public static final String INDEX_COLUMNS_CONF_KEY = "columnsToIndex";
private final DatasetDefinition<? extends Table, ?> tableDef;
public IndexedTableDefinition(String name, DatasetDefinition<? extends Table, ?> tableDef) {
super(name);
Preconditions.checkArgument(tableDef != null, "Table definition is required");
this.tableDef = tableDef;
}
@Override
public DatasetSpecification configure(String instanceName, DatasetProperties properties) {
return DatasetSpecification.builder(instanceName, getName())
.properties(properties.getProperties())
.datasets(tableDef.configure("d", properties),
tableDef.configure("i", properties))
.build();
}
@Override
public DatasetAdmin getAdmin(DatasetSpecification spec, ClassLoader classLoader) throws IOException {
return new CompositeDatasetAdmin(Lists.newArrayList(
tableDef.getAdmin(spec.getSpecification("d"), classLoader),
tableDef.getAdmin(spec.getSpecification("i"), classLoader)
));
}
@Override
public IndexedTable getDataset(DatasetSpecification spec,
Map<String, String> arguments, ClassLoader classLoader) throws IOException {
DatasetSpecification tableInstance = spec.getSpecification("d");
Table table = tableDef.getDataset(tableInstance, arguments, classLoader);
DatasetSpecification indexTableInstance = spec.getSpecification("i");
Table index = tableDef.getDataset(indexTableInstance, arguments, classLoader);
String columnNamesToIndex = spec.getProperty(INDEX_COLUMNS_CONF_KEY);
Preconditions.checkNotNull(columnNamesToIndex, "columnsToIndex must be specified");
String[] columns = columnNamesToIndex.split(",");
byte[][] columnsToIndex = new byte[columns.length][];
for (int i = 0; i < columns.length; i++) {
columnsToIndex[i] = Bytes.toBytes(columns[i]);
}
// TODO: add support for setting index key delimiter
return new IndexedTable(spec.getName(), table, index, columnsToIndex);
}
}