arraylist 在jsp中选择一个选项

Question

jsp中如何分配一个arraylist来选择一个选项？我找到了一个示例（how to assign arraylist to select option in jsp），但仍然有空选项。

IndexServlet.java

@WebServlet("/IndexServlet")
public class IndexServlet extends HttpServlet {

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        List<String> databaseArrayList = new ArrayList();
        databaseArrayList.add("1");
        databaseArrayList.add("2");
        databaseArrayList.add("3");
        request.setAttribute("databaseList", databaseArrayList);
        request.getRequestDispatcher("AddManager.jsp").forward(request, response);
        System.out.println("in index servlet");
}
}

Jsp代码

<tr>
            <td>Subordinate employees:</td>
            <td>
                <select name="database1">
                    <c:forEach items="${databaseList}" var="databaseValue">
                        <option value="${databaseValue}">
                                ${databaseValue}
                        </option>
                    </c:forEach>
                </select>
            </td>
        </tr>

Answer 1

您没有转发请求..

RequestDispatcher rd=request.getRequestDispatcher("/AddManager.jsp");          
rd.forward(request, response);