code: public void loadSystem() {
  		chooser.setDialogTitle("Open");
  		int resp = chooser.showOpenDialog(this);
  		if (resp == JFileChooser.APPROVE_OPTION) {
  			File file = chooser.getSelectedFile();
  			File path = file.getParentFile();
  			
  			try {
  				ParticleSystem system = ParticleIO.loadConfiguredSystem(file);
  				game.setSystem(system);
  				emitters.clear();
  				
  				for (int i=0;i<system.getEmitterCount();i++) {
  					final ConfigurableEmitter emitter = (ConfigurableEmitter) system.getEmitter(i);
  					
  					if (emitter.getImageName() != null) {
  						File possible = new File(path, emitter.getImageName());
  						if (possible.exists()) {
  							emitter.setImageName(possible.getAbsolutePath());
  						} else {
  							chooser.setDialogTitle("Locate the image: "+emitter.getImageName());
  							FileFilter filter = new FileFilter() {
  								public boolean accept(File f) {
  									if (f.isDirectory()) {
  										return true;
  									}
  									
  									return (f.getName().equals(emitter.getImageName()));
  								}
  	
  								public String getDescription() {
  									return emitter.getImageName();
  								}
  							};
  							
  							chooser.addChoosableFileFilter(filter);
  							resp = chooser.showOpenDialog(this);
  							if (resp == JFileChooser.APPROVE_OPTION) {
  								File image = chooser.getSelectedFile();
  								emitter.setImageName(image.getAbsolutePath());
  								path = image.getParentFile();
  							}
  							chooser.setDialogTitle("Open");
  							chooser.resetChoosableFileFilters();
  							chooser.addChoosableFileFilter(xmlFileFilter);
  						}
  					}
  					
  					emitters.add(emitter);
  				}
  				additive.setSelected(system.getBlendingMode() == ParticleSystem.BLEND_ADDITIVE);
  				pointsEnabled.setSelected(system.usePoints());
  				
  				emitters.setSelected(0);
  			} catch (IOException e) {
  				Log.error(e);
  				JOptionPane.showMessageDialog(this, e.getMessage());
  			}
  		}
  	}
docs: Load a complete particle system XML description