source: trunk/indexers/lucene-gs/src/org/greenstone/LuceneWrapper/LuceneQueryResult.java@ 13556

/**********************************************************************
 *
 * LuceneQueryResult.java 
 *
 * Copyright 2007 The New Zealand Digital Library Project
 *
 * A component of the Greenstone digital library software
 * from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *********************************************************************/

package org.nzdl.gsdl.LuceneWrap;

import java.util.Vector;

/** a QueryResult class for a lucene search
 *
 */
public class LuceneQueryResult {
    
    public static final int NO_ERROR = 0;
    public static final int PARSE_ERROR = 1;
    public static final int TOO_MANY_CLAUSES_ERROR = 2;
    public static final int IO_ERROR = 3;

    /** the list of DocInfo */
    protected Vector docs_=null;
    /** the list of TermInfo */
    protected Vector terms_=null;
    /** the list of stopwords found in the query */
    protected Vector stopwords_ = null;
    /** the total number of docs found - not necessarily the size of docs_*/
    protected int total_num_docs_=0;
    /** the start result number if we are retrieving only a portion of the results */
    protected int start_results_ = 0;
    /** the end result number if we are retrieving only a portion of the results */
    protected int end_results_ = 0;
    /** whether an error has occurred and what kind it is*/
    protected int error_ = NO_ERROR;

    LuceneQueryResult() {
    docs_ = new Vector();
    terms_ = new Vector();
    stopwords_ = new Vector();
    }
    
    /** clear the info from the last query - should be called before setting any new docs/terms */
    public void clear() {
    total_num_docs_=0;
    docs_.clear();
    terms_.clear();
    stopwords_.clear();
    error_ = NO_ERROR;
    }

    /** returns the result as a String - useful for printing out results */
    public String toString() {
    
    String result = "";
    result += "docs (ranks): ";
    for (int i=0; i<docs_.size(); i++) {
        result += ((DocInfo)docs_.elementAt(i)).toString()+", ";
    }
    result += "\nterms: ";
    for (int i=0; i<terms_.size(); i++) {
        result += ((TermInfo)terms_.elementAt(i)).toString()+", ";
    }
    result += "\nactual number of docs found = "+total_num_docs_;
    
    return result;
    }
    /** a shorter representation - just terms and total docs - not the 
    individual docnums and ranks */
    public String toShortString() {
    String result = "";
    result += "\nterms: ";
    for (int i=0; i<terms_.size(); i++) {
        result += ((TermInfo)terms_.elementAt(i)).toString()+", ";
    }
    result += "\nactual number of docs found = "+total_num_docs_;
    return result;
    }
    
    public void setTotalDocs(int num) {
    total_num_docs_=num;
    }
    
    public void setStartResults(int start) {
    start_results_ = start;
    }

    public void setEndResults(int end) {
    end_results_ = end;
    }

    public void addDoc(long doc, float rank) {
    DocInfo doc_info = new DocInfo(doc, rank);
    docs_.add(doc_info);
    }
    
    public void addTerm(String term, String field, int match, int freq) {
    TermInfo ti = new TermInfo();
    ti.term_=term;
    ti.field_=field;
    ti.match_docs_=match;
    ti.term_freq_=freq;
    terms_.add(ti);
    }
    public void addStopWord(String stopword) {
    stopwords_.add(stopword);
    }
    public Vector getDocs() {
    return docs_;
    }
    
    public int getError() {
    return error_;
    }
    
    public String getErrorString() {
    if (error_ == PARSE_ERROR) {
        return "PARSE_EXCEPTION";
    }
    if (error_ == TOO_MANY_CLAUSES_ERROR) {
        return "TOO_MANY_CLAUSES";
    }
    if (error_ == IO_ERROR) {
        return "IO_ERROR";
    }
    if (error_ == NO_ERROR) {
        return "NO_ERROR";
    }
    return "UNKNOWN";
    }

    public Vector getTerms() {
    return terms_;
    }
    
    public Vector getStopWords() {
    return stopwords_;
    }
    public int getTotalDocs() {
    return total_num_docs_;
    }
    
    public void setError(int error) {
    error_ = error;
    }
    
    public String getXMLString() {
    StringBuffer buffer = new StringBuffer();

    // terms
    buffer.append("<QueryTermsInfo num=\"" + terms_.size() + "\"/>\n");
    for (int i=0; i<terms_.size(); i++) {
        buffer.append(((TermInfo)terms_.elementAt(i)).toXMLString()+"\n");
    }

    // stopwords
    for (int i=0; i<stopwords_.size(); i++) {
        buffer.append("<StopWord value=\"" + (String)stopwords_.elementAt(i)+"\" />\n");
    }
    
    // results
    buffer.append("<MatchingDocsInfo num=\"" + total_num_docs_ + "\"/>\n");
    buffer.append("<StartResults num=\"" + start_results_ + "\"/>\n");
    buffer.append("<EndResults num=\"" + end_results_ + "\"/>\n");
    
    for (int i=0; i< docs_.size(); i++) {
        buffer.append(((DocInfo)docs_.elementAt(i)).toXMLString()+"\n");
    }

    return buffer.toString();
    }

 
    public class TermInfo {
    
    /** the term itself */
    public String term_=null;
    /** the field for which this term was queried */
    public String field_=null;
    /** the number of documents containing this term */
    public int match_docs_=0;
    /** overall term freq for this term */
    public int term_freq_=0;
    
    public TermInfo() {
    }
    
    /** output the class as a string */
    public String toString() {
        String result="";
        result +="<"+field_+">\""+term_+" docs("+match_docs_;
        result +=")freq("+term_freq_+")";
        return result;
    }

    /** output as an XML element */
    public String toXMLString() {
        return "<Term value=\"" + xmlSafe(term_) + "\" field=\"" + field_ + "\" freq=\"" + term_freq_ + "\" />";
    }
    }

    public class DocInfo {
    
    public long num_=0;
    public float rank_=0;
    
    public DocInfo(long doc, float rank) {
        num_=doc;
        rank_=rank;
    }
    public String toString(){
        return ""+num_+"("+rank_+")";
    }
    public String toXMLString() {
        return "<Match id=\"" + num_ + "\" rank=\"" + rank_ +"\" />";
    }
    }

    // where should this go???
    
    public static String xmlSafe(String text) {
    text = text.replaceAll("&","&amp;amp;");
    text = text.replaceAll("<","&amp;lt;");
    text = text.replaceAll(">","&amp;gt;");
    text = text.replaceAll("'","&amp;#039;");
    text = text.replaceAll("\\\"","&amp;quot;");
    return text;
    }
 
}