1 /**
2 * Copyright 2010 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.regionserver;
22
23 /**
24 * Implementors of this interface want to be notified when an HRegion
25 * determines that a cache flush is needed. A FlushRequester (or null)
26 * must be passed to the HRegion constructor so it knows who to call when it
27 * has a filled memstore.
28 */
29 public interface FlushRequester {
30 /**
31 * Tell the listener the cache needs to be flushed.
32 *
33 * @param region the HRegion requesting the cache flush
34 */
35 void request(HRegion region);
36 }