Cannot forward after response has been committed错误

按照一个视频课程敲的代码，但是执行完这块代码后，list.jsp始终跳转不过去，刚开始一直显示空白页，但是找不到报错的地方，后来调出一个报错提示：

Cannot forward after response has been committed

request.setCharacterEncoding("UTF-8");
		try {
			//1.取到了要查询的关键数据：姓名，性别 
			String sname = request.getParameter("sname");
			String sgender = request.getParameter("sgender");
			
			//2.找service去查询
			StudentService service = new StudentServiceImpl();
			List<Student> list = service.searchStudent(sname, sgender);
			
			System.out.println("list的大小是:"+list.size());
			for(Student student : list){
				System.out.println(student);
			
			//3.存数据
			request.setAttribute("list", list);
			
			//4.跳转
			request.getRequestDispatcher("list.jsp").forward(request, response);

解决办法是：

在***.forward(request, response);***的第二行什么代码都不要写，并且加一个return：

request.getRequestDispatcher(“list.jsp”).forward(request, response);
return;