| /* |
| * 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.lucene.index; |
| |
| import java.io.IOException; |
| |
| import org.apache.lucene.search.DocIdSetIterator; |
| |
| /** |
| * Source of {@link Impacts}. |
| * @lucene.internal |
| */ |
| public interface ImpactsSource { |
| |
| /** |
| * Shallow-advance to {@code target}. This is cheaper than calling |
| * {@link DocIdSetIterator#advance(int)} and allows further calls to |
| * {@link #getImpacts()} to ignore doc IDs that are less than {@code target} |
| * in order to get more precise information about impacts. |
| * This method may not be called on targets that are less than the current |
| * {@link DocIdSetIterator#docID()}. |
| * After this method has been called, {@link DocIdSetIterator#nextDoc()} may |
| * not be called if the current doc ID is less than {@code target - 1} and |
| * {@link DocIdSetIterator#advance(int)} may not be called on targets that |
| * are less than {@code target}. |
| */ |
| void advanceShallow(int target) throws IOException; |
| |
| /** |
| * Get information about upcoming impacts for doc ids that are greater than |
| * or equal to the maximum of {@link DocIdSetIterator#docID()} and the last |
| * target that was passed to {@link #advanceShallow(int)}. |
| * This method may not be called on an unpositioned iterator on which |
| * {@link #advanceShallow(int)} has never been called. |
| * NOTE: advancing this iterator may invalidate the returned impacts, so they |
| * should not be used after the iterator has been advanced. |
| */ |
| Impacts getImpacts() throws IOException; |
| |
| } |