com.browseengine.bobo.docidset.EmptyDocIdSet Maven / Gradle / Ivy
/**
* This software is licensed to you under the Apache License, Version 2.0 (the
* "Apache License").
*
* LinkedIn's contributions are made under the Apache License. If you contribute
* to the Software, the contributions will be deemed to have been made under the
* Apache License, unless you expressly indicate otherwise. Please do not make any
* contributions that would be inconsistent with the Apache License.
*
* You may obtain a copy of the Apache License at http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, this software
* distributed under the Apache License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the Apache
* License for the specific language governing permissions and limitations for the
* software governed under the Apache License.
*
* © 2012 LinkedIn Corp. All Rights Reserved.
*/
package com.browseengine.bobo.docidset;
import java.io.IOException;
import org.apache.lucene.search.DocIdSetIterator;
public final class EmptyDocIdSet extends RandomAccessDocIdSet
{
private static EmptyDocIdSet SINGLETON=new EmptyDocIdSet();
private static class EmptyDocIdSetIterator extends DocIdSetIterator
{
@Override
public int docID() { return -1; }
@Override
public int nextDoc() throws IOException { return DocIdSetIterator.NO_MORE_DOCS; }
@Override
public int advance(int target) throws IOException {return DocIdSetIterator.NO_MORE_DOCS; }
}
private static EmptyDocIdSetIterator SINGLETON_ITERATOR = new EmptyDocIdSetIterator();
private EmptyDocIdSet() { }
public static EmptyDocIdSet getInstance()
{
return SINGLETON;
}
@Override
public DocIdSetIterator iterator()
{
return SINGLETON_ITERATOR;
}
@Override
public boolean get(int docId)
{
return false;
}
}