/**
*
* 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.hbase.wal;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.NamespaceDescriptor;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.wal.RegionGroupingProvider.RegionGroupingStrategy;
/**
* A WAL grouping strategy based on namespace.
* Notice: the wal-group mapping might change if we support dynamic namespace updating later,
* and special attention needed if we support feature like group-based replication.
*/
@InterfaceAudience.Private
public class NamespaceGroupingStrategy implements RegionGroupingStrategy {
String providerId;
@Override
public String group(byte[] identifier, byte[] namespace) {
String namespaceString;
if (namespace == null || namespace.length == 0) {
namespaceString = NamespaceDescriptor.DEFAULT_NAMESPACE_NAME_STR;
} else {
namespaceString = Bytes.toString(namespace);
}
return providerId + GROUP_NAME_DELIMITER + namespaceString;
}
@Override
public void init(Configuration config, String providerId) {
this.providerId = providerId;
}
}