package org.apache.lucene.swing.models;
/**
* Copyright 2005 The Apache Software Foundation
*
* Licensed 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.
*/
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.WhitespaceAnalyzer;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.Fieldable;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.Hits;
import org.apache.lucene.queryParser.MultiFieldQueryParser;
import javax.swing.*;
import javax.swing.event.ListDataListener;
import javax.swing.event.ListDataEvent;
import java.util.ArrayList;
/**
* See table searcher explanation.
*
* @author Jonathan Simon - jonathan_s_simon@yahoo.com
*/
public class ListSearcher extends AbstractListModel {
private ListModel listModel;
/**
* The reference links between the decorated ListModel
* and this list model based on search criteria
*/
private ArrayList rowToModelIndex = new ArrayList();
/**
* In memory lucene index
*/
private RAMDirectory directory;
/**
* Cached lucene analyzer
*/
private Analyzer analyzer;
/**
* Links between this list model and the decorated list model
* are maintained through links based on row number. This is a
* key constant to denote "row number" for indexing
*/
private static final String ROW_NUMBER = "ROW_NUMBER";
/**
* Since we only have one field, unlike lists with multiple
* fields -- we are just using a constant to denote field name.
* This is most likely unnecessary and should be removed at
* a later date
*/
private static final String FIELD_NAME = "FIELD_NAME";
/**
* Cache the current search String. Also used internally to
* key whether there is an active search running or not. i.e. if
* searchString is null, there is no active search.
*/
private String searchString = null;
private ListDataListener listModelListener;
public ListSearcher(ListModel newModel) {
analyzer = new WhitespaceAnalyzer();
setListModel(newModel);
listModelListener = new ListModelHandler();
newModel.addListDataListener(listModelListener);
clearSearchingState();
}
private void setListModel(ListModel newModel) {
//remove listeners if there...
if (newModel != null) {
newModel.removeListDataListener(listModelListener);
}
listModel = newModel;
if (listModel != null) {
listModel.addListDataListener(listModelListener);
}
//recalculate the links between this list model and
//the inner list model since the decorated model just changed
reindex();
// let all listeners know the list has changed
fireContentsChanged(this, 0, getSize());
}
private void reindex() {
try {
// recreate the RAMDirectory
directory = new RAMDirectory();
IndexWriter writer = new IndexWriter(directory, analyzer, true);
// iterate through all rows
for (int row=0; row < listModel.getSize(); row++){
//for each row make a new document
Document document = new Document();
//add the row number of this row in the decorated list model
//this will allow us to retrive the results later
//and map this list model's row to a row in the decorated
//list model
document.add(new Field(ROW_NUMBER, "" + row, Field.Store.YES, Field.Index.TOKENIZED));
//add the string representation of the row to the index
document.add(new Field(FIELD_NAME, String.valueOf(listModel.getElementAt(row)).toLowerCase(), Field.Store.YES, Field.Index.TOKENIZED));
writer.addDocument(document);
}
writer.optimize();
writer.close();
} catch (Exception e){
e.printStackTrace();
}
}
/**
* Run a new search.
*
* @param searchString Any valid lucene search string
*/
public void search(String searchString){
//if search string is null or empty, clear the search == search all
if (searchString == null || searchString.equals("")){
clearSearchingState();
fireContentsChanged(this, 0, getSize());
return;
}
try {
//cache search String
this.searchString = searchString;
//make a new index searcher with the in memory (RAM) index.
IndexSearcher is = new IndexSearcher(directory);
//make an array of fields - one for each column
String[] fields = {FIELD_NAME};
//build a query based on the fields, searchString and cached analyzer
//NOTE: This is an area for improvement since the MultiFieldQueryParser
// has some weirdness.
MultiFieldQueryParser parser = new MultiFieldQueryParser(fields, analyzer);
Query query =parser.parse(searchString);
//run the search
Hits hits = is.search(query);
//reset this list model with the new results
resetSearchResults(hits);
} catch (Exception e){
e.printStackTrace();
}
//notify all listeners that the list has been changed
fireContentsChanged(this, 0, getSize());
}
/**
*
* @param hits The new result set to set this list to.
*/
private void resetSearchResults(Hits hits) {
try {
//clear our index mapping this list model rows to
//the decorated inner list model
rowToModelIndex.clear();
//iterate through the hits
//get the row number stored at the index
//that number is the row number of the decorated
//tabble model row that we are mapping to
for (int t=0; t<hits.length(); t++){
Document document = hits.doc(t);
Fieldable field = document.getField(ROW_NUMBER);
rowToModelIndex.add(new Integer(field.stringValue()));
}
} catch (Exception e){
e.printStackTrace();
}
}
/**
* @return The current lucene analyzer
*/
public Analyzer getAnalyzer() {
return analyzer;
}
/**
* @param analyzer The new analyzer to use
*/
public void setAnalyzer(Analyzer analyzer) {
this.analyzer = analyzer;
//reindex from the model with the new analyzer
reindex();
//rerun the search if there is an active search
if (isSearching()){
search(searchString);
}
}
private boolean isSearching() {
return searchString != null;
}
private void clearSearchingState() {
searchString = null;
rowToModelIndex.clear();
for (int t=0; t<listModel.getSize(); t++){
rowToModelIndex.add(new Integer(t));
}
}
private int getModelRow(int row){
return ((Integer) rowToModelIndex.get(row)).intValue();
}
public int getSize() {
return (listModel == null) ? 0 : rowToModelIndex.size();
}
public Object getElementAt(int index) {
return listModel.getElementAt(getModelRow(index));
}
class ListModelHandler implements ListDataListener {
public void contentsChanged(ListDataEvent e) {
somethingChanged();
}
public void intervalAdded(ListDataEvent e) {
somethingChanged();
}
public void intervalRemoved(ListDataEvent e) {
somethingChanged();
}
private void somethingChanged(){
// If we're not searching, just pass the event along.
if (!isSearching()) {
clearSearchingState();
reindex();
fireContentsChanged(ListSearcher.this, 0, getSize());
return;
}
// Something has happened to the data that may have invalidated the search.
reindex();
search(searchString);
fireContentsChanged(ListSearcher.this, 0, getSize());
return;
}
}
}
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