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/**
* 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.solr.search;
/**
* DocList represents the result of a query: an ordered list of document ids with optional score.
* This list contains a subset of the complete list of documents actually matched: size()
* document ids starting at offset().
*
* @version $Id: DocList.java 555343 2007-07-11 17:46:25Z hossman $
* @since solr 0.9
*/
public interface DocList extends DocSet {
/**
* Returns the zero based offset of this list within the total ordered list of matches to the query.
*/
public int offset();
/**
* Returns the number of ids in this list.
*/
public int size();
/**
* Returns the total number of matches for the search
* (as opposed to just the number collected according
* to offset() and size()).
* Hence it's always true that matches() >= size()
* @return number of matches for the search(query & any filters)
*/
public int matches();
/***
public int getDoc(int pos);
***/
// hmmm, what if a different slice could be generated from an existing DocSet
// (and was before)...
// how to distinguish cached values from logical values?
// docSet could represent docs 10-20, but actually contain 0-100
// should the big slice be cached independently, and a new class called
// DocListSubset be created to refer to a range within the DocList?
/**
* Get a subset of an existing DocList.
* Returns null if not possible.
*/
public DocList subset(int offset, int len);
/**
* Returns an iterator that may be used to iterate over the documents in this DocList
*
*
* The order of the documents returned by this iterator is based on the
* Sort order of the search that produced it. The Scoring information
* is meaningful only if hasScores() returns true.
*
* @see #hasScores
*/
public DocIterator iterator();
/** True if scores were retained */
public boolean hasScores();
/** The maximum score for the search... only valid if
* scores were retained (if hasScores()==true)
*/
public float maxScore();
}
/**** Maybe do this at a higher level (more efficient)
class SmartDocSet implements DocSet {
static int INITIAL_SIZE=10;
static int TRANSITION_SIZE=10;
protected BitSet bits;
int size;
protected int[] arr; // keep small set as an array, or as a hash?
protected int arrsize;
public SmartDocSet() {
if (INITIAL_SIZE>0) {
arr=new int[INITIAL_SIZE];
} else {
bits=new BitSet();
}
}
public void addUnique(int doc) {
size++;
if (bits != null) {
bits.set(doc);
}
else {
if (arrsize<10) {
arr[arrsize++]=doc;
} else {
// TODO: transition to bit set
}
}
};
public int size() {
return size;
}
public boolean exists(int docid) {
return false;
}
public DocSet intersection(DocSet other) {
return null;
}
public DocSet union(DocSet other) {
return null;
}
}
***/