org.apache.lucene.index.RandomAccessOrds Maven / Gradle / Ivy
/*
* 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;
/**
* Extension of {@link SortedSetDocValues} that supports random access
* to the ordinals of a document.
*
* Operations via this API are independent of the iterator api ({@link #nextOrd()})
* and do not impact its state.
*
* Codecs can optionally extend this API if they support constant-time access
* to ordinals for the document.
*/
public abstract class RandomAccessOrds extends SortedSetDocValues {
/** Sole constructor. (For invocation by subclass
* constructors, typically implicit.) */
protected RandomAccessOrds() {}
/**
* Retrieve the ordinal for the current document (previously
* set by {@link #setDocument(int)} at the specified index.
*
* An index ranges from {@code 0} to {@code cardinality()-1}.
* The first ordinal value is at index {@code 0}, the next at index {@code 1},
* and so on, as for array indexing.
* @param index index of the ordinal for the document.
* @return ordinal for the document at the specified index.
*/
public abstract long ordAt(int index);
/**
* Returns the cardinality for the current document (previously
* set by {@link #setDocument(int)}.
*/
public abstract int cardinality();
}