testindex.java

用于GIS(全球地理系统)的分析和处理的代码。

/*
 * This file is part of the GeOxygene project source files. 
 * 
 * GeOxygene aims at providing an open framework which implements OGC/ISO specifications for 
 * the development and deployment of geographic (GIS) applications. It is a open source 
 * contribution of the COGIT laboratory at the Institut G閛graphique National (the French 
 * National Mapping Agency).
 * 
 * See: http://oxygene-project.sourceforge.net 
 *  
 * Copyright (C) 2005 Institut G閛graphique National
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation; 
 * either version 2.1 of the License, or any later version.
 *
 * This library 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with 
 * this library (see file LICENSE if present); if not, write to the Free Software 
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *  
 */

package fr.ign.cogit.geoxygene.example;

import fr.ign.cogit.geoxygene.datatools.Geodatabase;
import fr.ign.cogit.geoxygene.datatools.ojb.GeodatabaseOjbFactory;
import fr.ign.cogit.geoxygene.feature.FT_Feature;
import fr.ign.cogit.geoxygene.feature.FT_FeatureCollection;
import fr.ign.cogit.geoxygene.spatial.coordgeom.GM_Envelope;
import fr.ign.cogit.geoxygene.spatial.coordgeom.GM_Polygon;
import fr.ign.cogit.geoxygene.util.index.Tiling;

/**
 * Exemple et test d'utilisation d'un index spatial (dallage) sur FT_FeatureCollection.
 * 
 * @author Thierry Badard & Arnaud Braun
 * @version 1.1
 * 
 */

public class TestIndex {

	private Geodatabase db;
	private Class featureClass;
    private String nomClasse = "geoxygene.geodata.Troncon_route"; 
	private FT_FeatureCollection featureList;
	private FT_FeatureCollection sublist;
	private GM_Envelope emprise;
	private long t1, t2;
		
	// ======= constructeur ===========================================
	private TestIndex() {

		// Classe geographique a charger
		try {
			featureClass = Class.forName(nomClasse);
		} catch (ClassNotFoundException e) {
			System.out.println(nomClasse + "classe geographique non trouvee");
			System.exit(0);
		}
		
		// Initialisation connexion a la BD
		db = GeodatabaseOjbFactory.newInstance();		
		db.begin();
		
		// Recherche du nombre d'objets a traiter
		int n = db.countObjects(featureClass);
		System.out.println("nombre d'objets a traiter : " + n);
		
		// Chargement de tous les objets
		System.out.print("chargement ... ");
		t1 = System.currentTimeMillis();
		featureList = db.loadAllFeatures(featureClass);
		t2 = System.currentTimeMillis();
		System.out.println( (t2-t1) / 1000.0 +" sec.");
		
		//Fermeture transaction
		db.commit();

	}


	// ======= main ===================================================
	public static void main(String args[]) {
		TestIndex test = new TestIndex();
		test.testPerf();
        test.testMiseAJour();
	}


	// ======= test des performances compare a Oracle =================
	private void testPerf() {	
        
        // Calcul de l'index
        System.out.print("calcul index ... ");
        t1 = System.currentTimeMillis();        
        featureList.initSpatialIndex( Tiling.class, false, 15 );
        t2 = System.currentTimeMillis();
        System.out.println( (t2-t1) / 1000.0 +" sec.");     	
		
        // emprise de la couche		
//		GM_Envelope empriseIni = db.getMetadata(featureClass).getEnvelope();  // lecture de l'emprise dans le SGBD
        GM_Envelope empriseIni = featureList.envelope(); // calcul direct
		
        // boucle pour regler la taille de l'emprise par homotheties successives
		for (double h=0.1; h<0.5; h += 0.1) {
			System.out.println("### coefficient d'extension de l'enveloppe "+h);
			emprise = (GM_Envelope) empriseIni.clone();
			emprise.expandBy(h);
			testGM_Envelope();
			testGM_Polygon();
			testOracle();
		}
	}
        

	// ======= selection index memoire avec une GM_Envelope ========	
	private void testGM_Envelope() {
		System.out.print("extraction GM_Envelope ... ");
		t1 = System.currentTimeMillis();		
		sublist =featureList.select(emprise);
		t2 = System.currentTimeMillis();		
		System.out.print("taille de la selection : "+sublist.size()+"\t");
		System.out.println("temps de calcul : "+ ((t2-t1)/1000.0) +" sec.");		
		sublist.clear();
	}

	
	// ======= selection index memoire avec un GM_Polygon ==========	
	private void testGM_Polygon() {
		System.out.print("extraction GM_Polygon  ... ");
		t1 = System.currentTimeMillis();		
		sublist =featureList.select(new GM_Polygon(emprise));
		t2 = System.currentTimeMillis();		
		System.out.print("taille de la selection : "+sublist.size()+"\t");
		System.out.println("temps de calcul : "+ ((t2-t1)/1000.0) +" sec.");		
		sublist.clear();
	}	
		
	
	// ======= selection avec Oracle =============================	
	private void testOracle() {		
		System.out.print("extraction oracle ...      ");
		t1 = System.currentTimeMillis();		
		sublist =db.loadAllFeatures(featureClass, new GM_Polygon(emprise));
		t2 = System.currentTimeMillis();		
		System.out.print("taille de la selection : "+sublist.size()+"\t");
		System.out.println("temps de calcul : "+ ((t2-t1)/1000.0) +" sec.");		
	}
    
    
    // ======= test des fonctions de mise a jour =================
    private void testMiseAJour() {
        
        featureList.initSpatialIndex( Tiling.class, true, 15 );
        Tiling dallage = (Tiling) featureList.getSpatialIndex();
        GM_Envelope env;
        
        // avant mise a jour
        FT_Feature feature =  featureList.get(10);
        System.out.println("ancienne taille : "+featureList.size());
        env = dallage.getDallage(feature) [0];
        System.out.println("dalle contenant le feature : "+env.hashCode());
        System.out.println("nombre d'objets dans cette dalle : "+featureList.select(env).size());

        // ajout
        FT_Feature newFeature =  feature.cloneGeom();
        newFeature.setGeom( (newFeature.getGeom().translate(1., 1., 0.)));
        featureList.add(newFeature);
        System.out.println("nouvelle taille : "+featureList.size()); 
        env = dallage.getDallage(feature) [0];
        System.out.println("dalle contenant le feature : "+env.hashCode());
        System.out.println("nombre d'objets dans cette dalle : "+featureList.select(env).size());

        // suppression
        featureList.remove(newFeature);
        System.out.println("nouvelle taille : "+featureList.size()); 
        env = dallage.getDallage(feature) [0];
        System.out.println("dalle contenant le feature : "+env.hashCode());
        System.out.println("nombre d'objets dans cette dalle : "+featureList.select(env).size());
    }
	
		
}