https://lucene.apache.org/lucene-parent/lucene-core: Apache Lucene Java Core (The Apache Software Foundation) 
/*
 * 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
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 */

package org.apache.lucene.search;

import java.io.IOException;


Per-segment, per-document long values, which can be calculated at search-time

/**
 * Per-segment, per-document long values, which can be calculated at search-time
 */
public abstract class LongValues {

  
Get the long value for the current document

/**
   * Get the long value for the current document
   */
  public abstract long longValue() throws IOException;

  
Advance this instance to the given document id

Returns:true if there is a value for this document
/**
   * Advance this instance to the given document id
   * @return true if there is a value for this document
   */
  public abstract boolean advanceExact(int doc) throws IOException;

}