重置密码问题

我想在用户扩展的基础上增加重置密码按钮:

public void resetPassword() {
            userManagementService.changeUserPassword(      ,    );
    }

请问一下changeUserPassword方法的第二个参数我该怎么写?他要求newPassworHash,密码哈希值怎么获取?是需要自己写么?有没有能调用的可自动生成密码哈希值得函数?

可以参考平台界面的方法:
com.haulmont.cuba.gui.app.security.user.changepassw.ChangePasswordDialog.changePassword

  public void changePassword() {
        if (validateAll()) {
            User targetUser;
            UUID targetUserId;
            if (user == null) {
                targetUserId = userSession.getUser().getId();
                targetUser = userSession.getUser();
            } else {
                targetUserId = user.getId();
                targetUser = user;
            }

            String newPassword = passwField.getValue();

            String passwordHash = passwordEncryption.getPasswordHash(targetUserId, newPassword);
            userManagementService.changeUserPassword(targetUserId, passwordHash);

            publishPasswordChangedEvent(targetUser, newPassword);

            showNotification(getMessage("passwordChanged"), NotificationType.HUMANIZED);

            close(COMMIT_ACTION_ID);
        }
    }

好的,非常感谢!