/*
* 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.client;
/**
* Enum describing the durability guarantees for {@link Mutation}
* Note that the items must be sorted in order of increasing durability
*/
public enum Durability {
/**
* Use the column family's default setting to determine durability.
* This must remain the first option.
*/
USE_DEFAULT,
/**
* Do not write the Mutation to the WAL
*/
SKIP_WAL,
/**
* Write the Mutation to the WAL asynchronously
*/
ASYNC_WAL,
/**
* Write the Mutation to the WAL synchronously.
* The data is flushed to the filesystem implementation, but not necessarily to disk.
* For HDFS this will flush the data to the designated number of DataNodes.
* See <a href="https://issues.apache.org/jira/browse/HADOOP-6313">HADOOP-6313<a/>
*/
SYNC_WAL,
/**
* Write the Mutation to the WAL synchronously and force the entries to disk.
* (Note: this is currently not supported and will behave identical to {@link #SYNC_WAL})
* See <a href="https://issues.apache.org/jira/browse/HADOOP-6313">HADOOP-6313<a/>
*/
FSYNC_WAL;
// efficiently translate ordinal back to items of this Enum
// (Enum.values()[ordinal] generates too much garbage)
public static Durability valueOf(int ordinal) {
switch (ordinal) {
case 0: return USE_DEFAULT;
case 1: return SKIP_WAL;
case 2: return ASYNC_WAL;
case 3: return SYNC_WAL;
case 4: return FSYNC_WAL;
default: throw new IllegalArgumentException("Unknown Durability Ordinal:"+ordinal);
}
}
}