Question

我在struts2中遇到标签问题。我真的不知道这个标签的执行情况

之前，我在我的数据库中有一个国家/地区列表，我希望将其放入<s:select>。我试过了 jsp页面（有我的标签）：

<s:select headerKey="-1" headerValue="Select Search Engines" list="country" name="yoursearch"></s:select>

动作类：

 public class ShowSelect extends ActionSupport{
    private List<String> country;



    public ShowSelect() {

        country = new ArrayList<String>();
        country.add("google.com");
        country.add("bing.com");
        country.add("yahoo.com");
        country.add("baidu.com");

    }
    public String display() {
        return "success";
    }

    public List<String> getSearchEngine() {
        return country;
    }

    public void setSearchEngine(List<String> country) {
        this.country = country;
    }

}

文件struts.xml

<action name="search" class="controller.ShowSelect">
   <result name="success">Select.jsp</result>
</action>

。但是，浏览器出现错误如下：

HTTP Status 500 -

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: tag 'select', field 'list': The requested list key '' could not be resolved as a collection/array/map/enumeration/iterator type. Example: people or people.{name} - [unknown location]
    org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:522)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:337)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:389)
root cause

tag 'select', field 'list': The requested list key '' could not be resolved as a collection/array/map/enumeration/iterator type. Example: people or people.{name} - [unknown location]
    org.apache.struts2.components.Component.fieldError(Component.java:237)
    org.apache.struts2.components.Component.findValue(Component.java:358)
    org.apache.struts2.components.ListUIBean.evaluateExtraParams(ListUIBean.java:80)
    org.apache.struts2.components.Select.evaluateExtraParams(Select.java:105)
    org.apache.struts2.components.UIBean.evaluateParams(UIBean.java:856)
    org.apache.struts2.components.UIBean.end(UIBean.java:510)
    org.apache.struts2.views.jsp.ComponentTagSupport.doEndTag(ComponentTagSupport.java:42)
    org.apache.jsp.Product.ShowListProduct_jsp._jspx_meth_s_005fselect_005f0(ShowListProduct_jsp.java:253)
    org.apache.jsp.Product.ShowListProduct_jsp._jspx_meth_s_005fdiv_005f0(ShowListProduct_jsp.java:115)
    org.apache.jsp.Product.ShowListProduct_jsp._jspService(ShowListProduct_jsp.java:70)
    org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:337)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:389)

我需要的是：通过Action类从数据库中获取列表

你可以帮帮我吗？请

Answer 1

它显示问题因为你没有吸气剂和动作类列表的setter。写getCountry()＆amp;你的行动中的setCountry()方法。它肯定会正常工作。

如何通过struts2框架中的Action类从数据库中获取数据（列表）到<s：select>标签</s：select>

1 个答案: