/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.hadoop.mapreduce.v2.hs;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapreduce.v2.jobhistory.JHAdminConfig;
import org.apache.hadoop.util.ReflectionUtils;
public class HistoryServerStateStoreServiceFactory {
/**
* Constructs an instance of the configured storage class
*
* @param conf the configuration
* @return the state storage instance
*/
public static HistoryServerStateStoreService getStore(Configuration conf) {
Class<? extends HistoryServerStateStoreService> storeClass =
HistoryServerNullStateStoreService.class;
boolean recoveryEnabled = conf.getBoolean(
JHAdminConfig.MR_HS_RECOVERY_ENABLE,
JHAdminConfig.DEFAULT_MR_HS_RECOVERY_ENABLE);
if (recoveryEnabled) {
storeClass = conf.getClass(JHAdminConfig.MR_HS_STATE_STORE, null,
HistoryServerStateStoreService.class);
if (storeClass == null) {
throw new RuntimeException("Unable to locate storage class, check "
+ JHAdminConfig.MR_HS_STATE_STORE);
}
}
return ReflectionUtils.newInstance(storeClass, conf);
}
}