public void buttonClick(ClickEvent event) {
final Window editWindow = new Window("Edit");
final PasswordField oldField = new PasswordField("Old Password");
final PasswordField newField = new PasswordField("New Password");
editWindow.addComponent(oldField);
editWindow.addComponent(newField);
Button saveButton = new Button("save");
editWindow.setImmediate(true);
saveButton.setImmediate(true);
saveButton.addListener(new ClickListener() {