Question

我尝试在成功登录后填充select标记，但系统出现以下错误。以下是代码。

struts.xml中

<package name="default" extends="struts-default">
    <action name="LoginAction" class="com.Struts2.Login.MDLogin">
        <result name="error">/Login/UILogin.jsp</result>
        <result name="success">/Login/UIRegister.jsp</result>
    </action>
    <action name="RegisterAction" class="com.Struts2.Register.MDRegister">
        <result name="error">/Login/UIRegister.jsp</result>
        <result name="success">/Login/UIRegisterData.jsp</result>
    </action>
    <action name="populateAction" method="populatePosition"   class="com.Struts2.Register.MDRegister">
        <result name="populate">/Login/UIRegister.jsp</result>
    </action>
</package>

UIRegister.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<%@ taglib uri="/struts-tags" prefix="s" %>    
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"     >
<html>
<head>
<META HTTP-EQUIV="Refresh" CONTENT="0;URL=populateAction.action">
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1;">
<title>Register</title>
</head>
<body>
<center>
Register Client
</center>
<s:form action="/RegisterAction">
<s:textfield name="txtUser" maxLength="10" size="10" label="User Name"/>    
<s:password name="txtPassword" label="Password" maxlength="15" size="15"/>
<s:textarea name="txtAbout" label="About you" col="20" row="3"></s:textarea>
<s:checkbox name="chkUpdate" label="check for the update" fieldValue="true" /
<s:select name="cboSelect" list="cboSelectList" listKey="strKey" istValue="strValue"                          
    multiple="false" label="Position"/>
<s:submit value="submit"></s:submit>
</s:form>
</body>
</html>

MDSelect.java

package com.Struts2.Select;

public class MDSelect 
{
private String strKey;
private String strValue;


public String getStrKey() {
    return strKey;
}


public void setStrKey(String strKey) {
    this.strKey = strKey;
}


public String getStrValue() {
    return strValue;
}


public void setStrValue(String strValue) {
    this.strValue = strValue;
}


public MDSelect(String strMainKey,String strMainValue)
{
    this.strKey=strMainKey;
    this.strValue=strMainValue;
}

 }

MDRegister.java

 package com.Struts2.Register;

 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Vector;

 import com.Struts2.Select.MDSelect;
 import com.Struts2.model.MDModel;
 import com.opensymphony.xwork2.ActionSupport;

 public class MDRegister extends ActionSupport 
 {
private String txtUser;
private String txtPassword;
private String txtAbout;
private String chkUpdate;
private String MDSelect;
private ArrayList<MDSelect> cboSelectList;
MDModel model=new MDModel();
public String getTxtUser() {
    return txtUser;
}

public void setTxtUser(String txtUser) {
    this.txtUser = txtUser;
}

public String getTxtPassword() {
    return txtPassword;
}

public void setTxtPassword(String txtPassword) {
    this.txtPassword = txtPassword;
}

public String getTxtAbout() {
    return txtAbout;
}

public void setTxtAbout(String txtAbout) {
    this.txtAbout = txtAbout;
}

public String getChkUpdate() {
    return chkUpdate;
}

public void setChkUpdate(String chkUpdate) {
    this.chkUpdate = chkUpdate;
}



public String getMDSelect() {
    return MDSelect;
}

public void setMDSelect(String mDSelect) {
    MDSelect = mDSelect;
}

public ArrayList<MDSelect> getCboSelectList() {
    return cboSelectList;
}

public void setCboSelectList(ArrayList<MDSelect> cboSelectList) {
    this.cboSelectList = cboSelectList;
}

public String populatePosition() throws SQLException
{
    Vector cboPosition=(Vector)model.cmbGCode("DPT");
     System.out.println("cboPosition>>>>>>>"+cboPosition.size());       
    cboSelectList=new ArrayList<MDSelect>();
    for(int iPos=0;iPos<cboPosition.size();iPos++)
    {
        Object[] objData=(Object[])cboPosition.elementAt(iPos);
        cboSelectList.add(new MDSelect(String.valueOf(objData[0]),        

                    String.valueOf(objData[1])));           
    }

    setCboSelectList(cboSelectList);
     System.out.println("In populate register 2 cboPosition>>>>>>>"+cboPosition.size());        
    return "populate";
}



public String execute()
{       
    if(getTxtUser().trim().equals(""))
    {
        addFieldError("txtUser", "User Can not be blank");
        return ERROR;
    }
    if(getTxtPassword().trim().equals(""))
    {
        addFieldError("txtPassword", "Password can not be blank");
        return ERROR;
    }
    if(getTxtAbout().trim().equals(""))
    {
        addFieldError("txtAbout", "Please tell us about your self");
        return ERROR;
    }

    return SUCCESS;
}

}

现在当我成功登录系统时，它会显示以下错误。

    HTTP Status 500 - tag 'select', field 'list', name 'cboSelect': The requested list  

    key 'cboSelectList' could not be resolved as a  
    collection/array/map/enumeration/iterator type. Example: people or people.{name} - [unknown location]

 type Exception report

 message tag 'select', field 'list', name 'cboSelect': The requested list key 'cboSelectList' could not be resolved as a collection/array/map/enumeration/iterator type.   Example: people or people.{name} - [unknown location]

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

Answer 1

您的应用程序存在一些缺陷。为LoginAction和RegistrationAction定义了无方法，因此在这种情况下，将为这两个操作调用 execute（）方法！

这是你想要的吗？并且由于你想在成功登录后填充select，它也会失败，因为你没有在execute（）中填充cboSelectedList，你一定会收到错误。

如果您是struts的新手，请立即了解Struts的基础知识！

成功登录后填充选择标记

1 个答案: