ssh框架前台弹出警告框

直接上代码：
action类实现下面的这个接口:
public class UserAdminAction extends ActionSupport implements ModelDriven, ServletResponseAware {

private HttpServletRequest request = null;
private HttpServletResponse response;

public HttpServletRequest getRequest() {
	return request;
}

public void setRequest(HttpServletRequest request) {
	this.request = request;
}

public HttpServletResponse getResponse() {
	return response;
}

public void setResponse(HttpServletResponse response) {
	this.response = response;
}


// 后台用户的删除
public String delete() {

	PageBean<Order> orders = orderService.findByUid(user.getUid(), 1);

	if (orders != null) {
		System.out.println("删除失败-----");
		response.setContentType("text/html;charset=UTF-8");
		response.setCharacterEncoding("UTF-8");// 防止弹出的信息出现乱码
		try {
			PrintWriter out = response.getWriter();
			out.print("<script>alert('此用户存在数据关联，请不要删除！')</script>");
			out.print(
					"<script>window.location.href='http://localhost:8080/shop/userAdmin_findAll1.action'</script>");
			out.flush();
			out.close();

		} catch (IOException e) {
			e.printStackTrace();
		}

	} else {
		User existUser = userService.findByUid(user.getUid());
		userService.delete(existUser);
		System.out.println("删除成功");
	}
	return "deleteSuccess";
}

public void setServletResponse(HttpServletResponse response) {
	this.response = response;

}

}