Small fixes (#9)

* Fixed null client causing exception when closing
* Adjusted users order in list
* Added code to store local input preferences

src/main/java/fr/igred/ij/plugin/frame/OMEROBatchPlugin.java

@@ -16,6 +16,7 @@
 import fr.igred.omero.repository.ImageWrapper;
 import fr.igred.omero.repository.ProjectWrapper;
 import ij.IJ;
+import ij.Prefs;
 import ij.plugin.frame.PlugInFrame;
 import loci.plugins.config.SpringUtilities;
 
@@ -225,6 +226,7 @@ public OMEROBatchPlugin() {
 		JButton inputFolderBtn = new JButton(browse);
 		inputFolderLabel.setLabelFor(inputFolder);
 		inputFolder.setMaximumSize(maxTextSize);
+		inputFolder.setName("omero.batch.dir.input");
 		input2.add(inputFolderLabel);
 		input2.add(inputFolder);
 		input2.add(inputFolderBtn);
@@ -246,6 +248,7 @@ public OMEROBatchPlugin() {
 		JButton macroBtn = new JButton(browse);
 		JButton argsBtn = new JButton("Set arguments");
 		macroLabel.setLabelFor(macro);
+		macro.setName("omero.batch.macro");
 		macro.setMaximumSize(maxTextSize);
 		macro1.add(macroLabel);
 		macro1.add(macro);
@@ -326,6 +329,7 @@ public OMEROBatchPlugin() {
 		JButton directoryBtn = new JButton(browse);
 		outputFolderLabel.setLabelFor(outputFolder);
 		outputFolder.setMaximumSize(maxTextSize);
+		outputFolder.setName("omero.batch.dir.output");
 		output3b.add(outputFolderLabel);
 		output3b.add(outputFolder);
 		output3b.add(directoryBtn);
@@ -411,7 +415,12 @@ public static void errorWindow(String message) {
 	 * @param textField The related text field.
 	 */
 	private static void chooseDirectory(JTextField textField) {
-		JFileChooser outputChoice = new JFileChooser(textField.getText());
+		String pref = textField.getName();
+		if(pref.isEmpty()) pref = "omero.batch." + Prefs.DIR_IMAGE;
+		String previousDir = textField.getText();
+		if(previousDir.isEmpty()) previousDir = Prefs.get(pref, previousDir);
+
+		JFileChooser outputChoice = new JFileChooser(previousDir);
 		outputChoice.setDialogTitle("Choose the directory");
 		outputChoice.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
 		int returnVal = outputChoice.showOpenDialog(null);
@@ -421,6 +430,7 @@ private static void chooseDirectory(JTextField textField) {
 											   .getAbsolutePath());
 			if (absDir.exists() && absDir.isDirectory()) {
 				textField.setText(absDir.toString());
+				Prefs.set(pref, absDir.toString());
 			} else {
 				////find a way to prevent JFileChooser closure?
 				errorWindow(String.format("Output:%nThe directory doesn't exist"));
@@ -638,6 +648,7 @@ private void updateGroup(ItemEvent e) {
 			} catch (ExecutionException | ServiceException | AccessException exception) {
 				LOGGER.warning(exception.getMessage());
 			}
+			users.sort(Comparator.comparing(ExperimenterWrapper::getUserName));
 			userList.removeAllItems();
 
 			userList.addItem("All members");
@@ -690,14 +701,20 @@ private void updateInput(ItemEvent e) {
 	 * Displays a dialog to select the macro to run.
 	 */
 	private void chooseMacro() {
-		JFileChooser macroChoice = new JFileChooser(macro.getText());
+		String pref = macro.getName().isEmpty() ? "omero.batch.macro" : macro.getName();
+		String previousMacro = macro.getText();
+		if(previousMacro.isEmpty()) {
+			previousMacro = Prefs.get(pref, previousMacro);
+		}
+		JFileChooser macroChoice = new JFileChooser(previousMacro);
 		macroChoice.setDialogTitle("Choose the macro file");
 		macroChoice.setFileSelectionMode(JFileChooser.FILES_ONLY);
 		int returnVal = macroChoice.showOpenDialog(null);
 		if (returnVal == JFileChooser.APPROVE_OPTION) {
 			File absFile = new File(macroChoice.getSelectedFile().getAbsolutePath());
 			if (absFile.exists() && !absFile.isDirectory()) {
 				macro.setText(absFile.toString());
+				Prefs.set(pref, absFile.toString());
 			} else {
 				//find a way to prevent JFileChooser closure?
 				warningWindow(String.format("Macro:%nThe file doesn't exist"));
@@ -1120,7 +1137,8 @@ private class ClientDisconnector extends WindowAdapter {
 		@Override
 		public void windowClosing(WindowEvent e) {
 			super.windowClosing(e);
-			client.disconnect();
+			Client c = client;
+			if(c != null) c.disconnect();
 		}
 
 	}