hbase-client/src/main/java/org/apache/hadoop/hbase/client/IsolationLevel.java

   1 /*
   2  * Copyright The Apache Software Foundation
   3  *
   4  * Licensed to the Apache Software Foundation (ASF) under one
   5  * or more contributor license agreements.  See the NOTICE file
   6  * distributed with this work for additional information
   7  * regarding copyright ownership.  The ASF licenses this file
   8  * to you under the Apache License, Version 2.0 (the
   9  * "License"); you may not use this file except in compliance
  10  * with the License.  You may obtain a copy of the License at
  11  *
  12  *     http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  */
  20
  21 package org.apache.hadoop.hbase.client;
  22
  23 import org.apache.yetus.audience.InterfaceAudience;
  24
  25 /**
  26  * Specify Isolation levels in Scan operations.
  27  * <p>
  28  * There are two isolation levels. A READ_COMMITTED isolation level
  29  * indicates that only data that is committed be returned in a scan.
  30  * An isolation level of READ_UNCOMMITTED indicates that a scan
  31  * should return data that is being modified by transactions that might
  32  * not have been committed yet.
  33  */
  34 @InterfaceAudience.Public
  35 public enum IsolationLevel {
  36
  37   READ_COMMITTED(1),
  38   READ_UNCOMMITTED(2);
  39
  40   IsolationLevel(int value) {}
  41
  42   public byte [] toBytes() {
  43     return new byte [] { toByte() };
  44   }
  45
  46   public byte toByte() {
  47     return (byte)this.ordinal();
  48   }
  49
  50   public static IsolationLevel fromBytes(byte [] bytes) {
  51     return IsolationLevel.fromByte(bytes[0]);
  52   }
  53
  54   public static IsolationLevel fromByte(byte vbyte) {
  55     return IsolationLevel.values()[vbyte];
  56   }
  57 }