package org.apache.lucene.index;
/**
* 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.
*/
import java.io.IOException;
/**
* A {@link MergeScheduler} which never executes any merges. It is also a
* singleton and can be accessed through {@link NoMergeScheduler#INSTANCE}. Use
* it if you want to prevent an {@link IndexWriter} from ever executing merges,
* irregardles of the {@link MergePolicy} used. Note that you can achieve the
* same thing by using {@link NoMergePolicy}, however with
* {@link NoMergeScheduler} you also ensure that no unnecessary code of any
* {@link MergeScheduler} implementation is ever executed. Hence it is
* recommended to use both if you want to disable merges from ever happening.
*/
public final class NoMergeScheduler extends MergeScheduler {
/** The single instance of {@link NoMergeScheduler} */
public static final MergeScheduler INSTANCE = new NoMergeScheduler();
private NoMergeScheduler() {
// prevent instantiation
}
@Override
public void close() {}
@Override
public void merge(IndexWriter writer) throws CorruptIndexException, IOException {}
}