@Override
    protected void onBind() {
        super.onBind();
        registerHandler(createButton.addClickHandler(e -> {
            if (MouseUtil.isPrimary(e)) {
                onCreateUserOrGroup();
            }
        }));
//        registerHandler(editButton.addClickHandler(e -> {
//            if (MouseUtil.isPrimary(e)) {
//                onEditUserOrGroup();
//            }
//        }));
        registerHandler(deleteButton.addClickHandler(e -> {
            if (MouseUtil.isPrimary(e)) {
                onDelete();
            }
        }));
        registerHandler(userList.getSelectionModel().addSelectionHandler(e -> {
            onSelection();
        }));
    }
For managing all the users (not groups)
stroom-core-client/src/main/java/stroom/security/client/presenter/UsersPresenter.java