*** Hits.java	17 Feb 2004 19:00:31 -0000	1.9
--- Hits.java	26 Feb 2004 19:23:10 -0000
***************
*** 1,215 ****
! package org.apache.lucene.search;
! 
! /* ====================================================================
!  * The Apache Software License, Version 1.1
!  *
!  * Copyright (c) 2001 The Apache Software Foundation.  All rights
!  * reserved.
!  *
!  * Redistribution and use in source and binary forms, with or without
!  * modification, are permitted provided that the following conditions
!  * are met:
!  *
!  * 1. Redistributions of source code must retain the above copyright
!  *    notice, this list of conditions and the following disclaimer.
!  *
!  * 2. Redistributions in binary form must reproduce the above copyright
!  *    notice, this list of conditions and the following disclaimer in
!  *    the documentation and/or other materials provided with the
!  *    distribution.
!  *
!  * 3. The end-user documentation included with the redistribution,
!  *    if any, must include the following acknowledgment:
!  *       "This product includes software developed by the
!  *        Apache Software Foundation (http://www.apache.org/)."
!  *    Alternately, this acknowledgment may appear in the software itself,
!  *    if and wherever such third-party acknowledgments normally appear.
!  *
!  * 4. The names "Apache" and "Apache Software Foundation" and
!  *    "Apache Lucene" must not be used to endorse or promote products
!  *    derived from this software without prior written permission. For
!  *    written permission, please contact apache@apache.org.
!  *
!  * 5. Products derived from this software may not be called "Apache",
!  *    "Apache Lucene", nor may "Apache" appear in their name, without
!  *    prior written permission of the Apache Software Foundation.
!  *
!  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
!  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
!  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
!  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
!  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
!  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
!  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
!  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
!  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
!  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
!  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
!  * SUCH DAMAGE.
!  * ====================================================================
!  *
!  * This software consists of voluntary contributions made by many
!  * individuals on behalf of the Apache Software Foundation.  For more
!  * information on the Apache Software Foundation, please see
!  * <http://www.apache.org/>.
!  */
! 
! import java.io.IOException;
! import java.util.Vector;
! 
! import org.apache.lucene.document.Document;
! 
! /** A ranked list of documents, used to hold search results. */
! public final class Hits {
!   private Query query;
!   private Searcher searcher;
!   private Filter filter = null;
!   private Sort sort = null;
! 
!   private int length;				  // the total number of hits
!   private Vector hitDocs = new Vector();	  // cache of hits retrieved
! 
!   private HitDoc first;         // head of LRU cache
!   private HitDoc last;          // tail of LRU cache
!   private int numDocs = 0;      // number cached
!   private int maxDocs = 200;    // max to cache
! 
!   Hits(Searcher s, Query q, Filter f) throws IOException {
!     query = q;
!     searcher = s;
!     filter = f;
!     getMoreDocs(50); // retrieve 100 initially
!   }
! 
!   Hits(Searcher s, Query q, Filter f, Sort o) throws IOException {
!     query = q;
!     searcher = s;
!     filter = f;
!     sort = o;
!     getMoreDocs(50); // retrieve 100 initially
!   }
! 
!   /**
!    * Tries to add new documents to hitDocs.
!    * Ensures that the hit numbered <code>min</code> has been retrieved.
!    */
!   private final void getMoreDocs(int min) throws IOException {
!     if (hitDocs.size() > min) {
!       min = hitDocs.size();
!     }
! 
!     int n = min * 2;	// double # retrieved
!     TopDocs topDocs = (sort == null) ? searcher.search(query, filter, n) : searcher.search(query, filter, n, sort);
!     length = topDocs.totalHits;
!     ScoreDoc[] scoreDocs = topDocs.scoreDocs;
! 
!     float scoreNorm = 1.0f;
!     if (length > 0 && scoreDocs[0].score > 1.0f) {
!       scoreNorm = 1.0f / scoreDocs[0].score;
!     }
! 
!     int end = scoreDocs.length < length ? scoreDocs.length : length;
!     for (int i = hitDocs.size(); i < end; i++) {
!       hitDocs.addElement(new HitDoc(scoreDocs[i].score * scoreNorm,
!                                     scoreDocs[i].doc));
!     }
!   }
! 
!   /** Returns the total number of hits available in this set. */
!   public final int length() {
!     return length;
!   }
! 
!   /** Returns the nth document in this set.
!    <p>Documents are cached, so that repeated requests for the same element may
!    return the same Document object. */
!   public final Document doc(int n) throws IOException {
!     HitDoc hitDoc = hitDoc(n);
! 
!     // Update LRU cache of documents
!     remove(hitDoc);               // remove from list, if there
!     addToFront(hitDoc);           // add to front of list
!     if (numDocs > maxDocs) {      // if cache is full
!       HitDoc oldLast = last;
!       remove(last);             // flush last
!       oldLast.doc = null;       // let doc get gc'd
!     }
! 
!     if (hitDoc.doc == null) {
!       hitDoc.doc = searcher.doc(hitDoc.id);  // cache miss: read document
!     }
! 
!     return hitDoc.doc;
!   }
! 
!   /** Returns the score for the nth document in this set. */
!   public final float score(int n) throws IOException {
!     return hitDoc(n).score;
!   }
! 
!   /** Returns the id for the nth document in this set. */
!   public final int id(int n) throws IOException {
!     return hitDoc(n).id;
!   }
! 
! 
!   private final HitDoc hitDoc(int n) throws IOException {
!     if (n >= length) {
!       throw new IndexOutOfBoundsException("Not a valid hit number: " + n);
!     }
! 
!     if (n >= hitDocs.size()) {
!       getMoreDocs(n);
!     }
! 
!     return (HitDoc) hitDocs.elementAt(n);
!   }
! 
!   private final void addToFront(HitDoc hitDoc) {  // insert at front of cache
!     if (first == null) {
!       last = hitDoc;
!     } else {
!       first.prev = hitDoc;
!     }
! 
!     hitDoc.next = first;
!     first = hitDoc;
!     hitDoc.prev = null;
! 
!     numDocs++;
!   }
! 
!   private final void remove(HitDoc hitDoc) {	  // remove from cache
!     if (hitDoc.doc == null) {     // it's not in the list
!       return;					  // abort
!     }
! 
!     if (hitDoc.next == null) {
!       last = hitDoc.prev;
!     } else {
!       hitDoc.next.prev = hitDoc.prev;
!     }
! 
!     if (hitDoc.prev == null) {
!       first = hitDoc.next;
!     } else {
!       hitDoc.prev.next = hitDoc.next;
!     }
! 
!     numDocs--;
!   }
! }
! 
! final class HitDoc {
!   float score;
!   int id;
!   Document doc = null;
! 
!   HitDoc next;  // in doubly-linked cache
!   HitDoc prev;  // in doubly-linked cache
! 
!   HitDoc(float s, int i) {
!     score = s;
!     id = i;
!   }
! }
--- 1,225 ----
! package org.apache.lucene.search;
! 
! /* ====================================================================
!  * The Apache Software License, Version 1.1
!  *
!  * Copyright (c) 2001 The Apache Software Foundation.  All rights
!  * reserved.
!  *
!  * Redistribution and use in source and binary forms, with or without
!  * modification, are permitted provided that the following conditions
!  * are met:
!  *
!  * 1. Redistributions of source code must retain the above copyright
!  *    notice, this list of conditions and the following disclaimer.
!  *
!  * 2. Redistributions in binary form must reproduce the above copyright
!  *    notice, this list of conditions and the following disclaimer in
!  *    the documentation and/or other materials provided with the
!  *    distribution.
!  *
!  * 3. The end-user documentation included with the redistribution,
!  *    if any, must include the following acknowledgment:
!  *       "This product includes software developed by the
!  *        Apache Software Foundation (http://www.apache.org/)."
!  *    Alternately, this acknowledgment may appear in the software itself,
!  *    if and wherever such third-party acknowledgments normally appear.
!  *
!  * 4. The names "Apache" and "Apache Software Foundation" and
!  *    "Apache Lucene" must not be used to endorse or promote products
!  *    derived from this software without prior written permission. For
!  *    written permission, please contact apache@apache.org.
!  *
!  * 5. Products derived from this software may not be called "Apache",
!  *    "Apache Lucene", nor may "Apache" appear in their name, without
!  *    prior written permission of the Apache Software Foundation.
!  *
!  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
!  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
!  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
!  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
!  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
!  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
!  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
!  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
!  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
!  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
!  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
!  * SUCH DAMAGE.
!  * ====================================================================
!  *
!  * This software consists of voluntary contributions made by many
!  * individuals on behalf of the Apache Software Foundation.  For more
!  * information on the Apache Software Foundation, please see
!  * <http://www.apache.org/>.
!  */
! 
! import java.io.IOException;
! import java.util.Vector;
! 
! import org.apache.lucene.document.Document;
! 
! /** A ranked list of documents, used to hold search results. */
! public final class Hits {
!   private Query query;
!   private Searcher searcher;
!   private Filter filter = null;
!   private Sort sort = null;
! 
!   private int length;				  // the total number of hits
!   private Vector hitDocs = new Vector();	  // cache of hits retrieved
! 
!   private HitDoc first;         // head of LRU cache
!   private HitDoc last;          // tail of LRU cache
!   private int numDocs = 0;      // number cached
!   private int maxDocs = 200;    // max to cache
! 
!   Hits(Searcher s, Query q, Filter f) throws IOException {
!     query = q;
!     searcher = s;
!     filter = f;
!     getMoreDocs(50); // retrieve 100 initially
!   }
! 
!   Hits(Searcher s, Query q, Filter f, Sort o) throws IOException {
!     query = q;
!     searcher = s;
!     filter = f;
!     sort = o;
!     getMoreDocs(50); // retrieve 100 initially
!   }
! 
!   /** Returns the searcher. */
!   public final Searcher getSearcher() {
!   	return searcher;
!   }
! 
!   /** Sets the searcher. */
!   public final void setSearcher(Searcher s) {
!   	searcher = s;
!   }
! 
!   /**
!    * Tries to add new documents to hitDocs.
!    * Ensures that the hit numbered <code>min</code> has been retrieved.
!    */
!   private final void getMoreDocs(int min) throws IOException {
!     if (hitDocs.size() > min) {
!       min = hitDocs.size();
!     }
! 
!     int n = min * 2;	// double # retrieved
!     TopDocs topDocs = (sort == null) ? searcher.search(query, filter, n) : searcher.search(query, filter, n, sort);
!     length = topDocs.totalHits;
!     ScoreDoc[] scoreDocs = topDocs.scoreDocs;
! 
!     float scoreNorm = 1.0f;
!     if (length > 0 && scoreDocs[0].score > 1.0f) {
!       scoreNorm = 1.0f / scoreDocs[0].score;
!     }
! 
!     int end = scoreDocs.length < length ? scoreDocs.length : length;
!     for (int i = hitDocs.size(); i < end; i++) {
!       hitDocs.addElement(new HitDoc(scoreDocs[i].score * scoreNorm,
!                                     scoreDocs[i].doc));
!     }
!   }
! 
!   /** Returns the total number of hits available in this set. */
!   public final int length() {
!     return length;
!   }
! 
!   /** Returns the nth document in this set.
!    <p>Documents are cached, so that repeated requests for the same element may
!    return the same Document object. */
!   public final Document doc(int n) throws IOException {
!     HitDoc hitDoc = hitDoc(n);
! 
!     // Update LRU cache of documents
!     remove(hitDoc);               // remove from list, if there
!     addToFront(hitDoc);           // add to front of list
!     if (numDocs > maxDocs) {      // if cache is full
!       HitDoc oldLast = last;
!       remove(last);             // flush last
!       oldLast.doc = null;       // let doc get gc'd
!     }
! 
!     if (hitDoc.doc == null) {
!       hitDoc.doc = searcher.doc(hitDoc.id);  // cache miss: read document
!     }
! 
!     return hitDoc.doc;
!   }
! 
!   /** Returns the score for the nth document in this set. */
!   public final float score(int n) throws IOException {
!     return hitDoc(n).score;
!   }
! 
!   /** Returns the id for the nth document in this set. */
!   public final int id(int n) throws IOException {
!     return hitDoc(n).id;
!   }
! 
! 
!   private final HitDoc hitDoc(int n) throws IOException {
!     if (n >= length) {
!       throw new IndexOutOfBoundsException("Not a valid hit number: " + n);
!     }
! 
!     if (n >= hitDocs.size()) {
!       getMoreDocs(n);
!     }
! 
!     return (HitDoc) hitDocs.elementAt(n);
!   }
! 
!   private final void addToFront(HitDoc hitDoc) {  // insert at front of cache
!     if (first == null) {
!       last = hitDoc;
!     } else {
!       first.prev = hitDoc;
!     }
! 
!     hitDoc.next = first;
!     first = hitDoc;
!     hitDoc.prev = null;
! 
!     numDocs++;
!   }
! 
!   private final void remove(HitDoc hitDoc) {	  // remove from cache
!     if (hitDoc.doc == null) {     // it's not in the list
!       return;					  // abort
!     }
! 
!     if (hitDoc.next == null) {
!       last = hitDoc.prev;
!     } else {
!       hitDoc.next.prev = hitDoc.prev;
!     }
! 
!     if (hitDoc.prev == null) {
!       first = hitDoc.next;
!     } else {
!       hitDoc.prev.next = hitDoc.next;
!     }
! 
!     numDocs--;
!   }
! }
! 
! final class HitDoc {
!   float score;
!   int id;
!   Document doc = null;
! 
!   HitDoc next;  // in doubly-linked cache
!   HitDoc prev;  // in doubly-linked cache
! 
!   HitDoc(float s, int i) {
!     score = s;
!     id = i;
!   }
! }