如何使用复选框列表在struts 2中获取多个复选框值

Question

嗨，我是 struts 2 的新手， 有人可以告诉我如何在 struts 2 中获取多个复选框值。 到目前为止，我已经开发了如下代码。 我收到错误

tag 'checkboxlist', field 'list', name 'subscribe': The requested list key 'subscription' could not be resolved as a collection/array/map/enumeration/iterator type. Example: people or people.{name} - [unknown location]
    at org.apache.struts2.components.Component.fieldError(Component.java:240)
    at org.apache.struts2.components.Component.findValue(Component.java:333)
    at org.apache.struts2.components.ListUIBean.evaluateExtraParams(ListUIBean.java:80)
    at org.apache.struts2.components.UIBean.evaluateParams(UIBean.java:875)
    at org.apache.struts2.components.UIBean.end(UIBean.java:523)
    at org.apache.struts2.views.jsp.ComponentTagSupport.doEndTag(ComponentTagSupport.java:42)
    at jsp_servlet.__step1._jsp__tag6(__step1.java:371)
    at jsp_servlet.__step1._jsp__tag0(__step1.java:148)
    at jsp_servlet.__step1._jspService(__step1.java:86)
    at weblogic.servlet.jsp.JspBase.service(JspBase.java:34)
    at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)

我获取值的jsp页面是

 <link href="style.css" rel="stylesheet" type="text/css"/>
 <%@ taglib uri="/struts-tags" prefix="s" %>

 <table class="profiletable" align="center">
<tr>
    <td align="center"><h2>Upload User Profile</h2></td>
</tr>
<tr>
    <td align="center"><s:form action="upload" method="post">
<s:textfield name="fname" label="First Name"></s:textfield>
<s:textfield name="lname" label="Last Name"></s:textfield>
<s:radio name="mstatus" label="Martial Status" list="{'Single','Married'}"></s:radio>
<s:radio name="gender" label="Gender" list="{'male','female'}"></s:radio>
<s:select list="{'India','USA','UK','Germany','France','Australia'}" label="Country" name="country"></s:select>
 <s:checkboxlist label="Letter you want to subscribe" name="subscribe" list="subscription" />
  <s:submit value="upload profile" align="center"></s:submit>
</s:form></td>
</tr>
 </table>

我的jsp页面显示值是

<%@ taglib uri="/struts-tags" prefix="p" %>
<h2>Profile uploaded sucessfully</h2>
 First Name:<p:property value="fname"/><br/>
Last Name:<p:property value="lname"/><br/>
Martial status:<p:property value="mstatus"/><br/>
Gender:<p:property value="gender"/><br/>
Country:<p:property value="country"/><br/>
Letters Subscribed:<p:property value="subscribe"/>/>

我的动作文件是

package com.javapoint;

import java.util.ArrayList;
 import java.util.List;

import com.opensymphony.xwork2.ActionSupport;



 public class UploadProfile extends ActionSupport {

/**
 * 
 */
private static final long serialVersionUID = 1L;
private String fname;
private String lname;
private String mstatus;
private String gender;
private String country;
private String subscribe;
private List<String> subscription;

public String getFname() {
    System.out.println("inside getfname");
    return fname;
}
public void setFname(String fname) {
    System.out.println("inside getfname");
    System.out.println("the firstname set is "+fname);
    this.fname = fname;
}
public String getLname() {

    return lname;
}
public void setLname(String lname) {
    this.lname = lname;
    System.out.println("the lastname set is "+ lname);
}
public String getMstatus() {
    return mstatus;
}
public void setMstatus(String mstatus) {
    this.mstatus = mstatus;
}
public String getGender() {
    return gender;
}
public void setGender(String gender) {
    this.gender = gender;
}
public String getCountry() {
    return country;
}
public void setCountry(String country) {
    this.country = country;
}

public String getSubscribe() {
    return subscribe;
}
public void setSubscribe(String subscribe) {
    this.subscribe = subscribe;
}
public List<String> getSubscription() {
    return subscription;
}
public void setSubscription(List<String> subscription) {
    this.subscription = subscription;
}
public UploadProfile(){
    subscription=new ArrayList<String>();
    subscription.add("Politics");
    subscription.add("Sports");
    subscription.add("Editorial");
    subscription.add("Gadgets");
    subscription.add("Overdrive");
}
public String execute()throws Exception{
    System.out.println("inside execute");
    if(fname!=null){
    return "profileuploaded";
    }else{
        return "error";

    }
}

public String display(){

    return NONE;
}


}

我的 struts.xml 文件是

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts
Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
<struts>
 <package name="default" extends="struts-default">

<action name="product" class="com.javapoint.Product">
<result name="success">welcome.jsp</result>
</action>
<action name="upload" class="com.javapoint.UploadProfile">
<result name="profileuploaded">ProfileUploaded.jsp</result>
 <result name="error">index.jsp</result>
</action>
</package>
  </struts>    

我的 web.xml 文件是

<?xml version="1.0" encoding="UTF-8"?>
<web-app>
<filter>
<filter-name>struts2</filter-name>
<filter-class>
org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
  </filter-class>
 </filter>
  <filter-mapping>
   <filter-name>struts2</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <welcome-file-list>
  <welcome-file>step1.jsp</welcome-file>
   </welcome-file-list>

Answer 1

1. struts.xml：

<action name="subscription_listing" method="UploadProfile" class="com.javapoint.UploadProfile" > <result name="none">/your_jsppage_where_you_have_checkboxlist</result> </action>

2.在Uploadprofile Action类中修改Uploadprofile方法：

public String UploadProfile(){
subscription=new ArrayList<String>();
subscription.add("Politics");
subscription.add("Sports");
subscription.add("Editorial");
subscription.add("Gadgets");
subscription.add("Overdrive");
return NONE;

}

[3]。现在直接调用subscription_listing action。

你明白了吗？

Answer 2

由于您是 Struts2 的新手，希望这个 example 可以帮助您在 struts2 中使用多个复选框

Answer 3

在浏览并实施上述建议之后，我已经得出了在 chekbox 的情况下直接调用动作文件的解决方案，虽然可以有替代方案，但目前我还不知道。

问题出在我的 struts.xml 上，应该是

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts
 Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
 <struts>
 <package name="default" extends="struts-default">

 <action name="upload" class="com.javapoint.UploadProfile">
 <result name="profileuploaded">ProfileUploaded.jsp</result>
  <result name="error">index.jsp</result>


 </action>
<action name="UploadProfile" class="com.javapoint.UploadProfile" method="display">
    <result name="none">/step1.jsp</result>
   </action>

</package>
</struts>    

最后的动作文件是

包com.javapoint;

导入 java.util.ArrayList; 导入 java.util.List;

导入 com.opensymphony.xwork2.ActionSupport;

公共类 UploadProfile 扩展 ActionSupport {

/**
 * 
 */
private static final long serialVersionUID = 1L;
private String fname;
private String lname;
private String mstatus;
private String gender;
private String country;
private String[] defaultsubscription;
private String[] yoursubscription;
private List<String> subscription;

public String getFname() {
    System.out.println("inside getfname");
    return fname;
}
public void setFname(String fname) {
    System.out.println("inside getfname");
    System.out.println("the firstname set is "+fname);
    this.fname = fname;
}
public String getLname() {

    return lname;
}
public void setLname(String lname) {
    this.lname = lname;
    System.out.println("the lastname set is "+ lname);
}
public String getMstatus() {
    return mstatus;
}
public void setMstatus(String mstatus) {
    this.mstatus = mstatus;
}
public String getGender() {
    return gender;
}
public void setGender(String gender) {
    this.gender = gender;
}
public String getCountry() {
    return country;
}
public void setCountry(String country) {
    this.country = country;
System.out.println(country);
}

public String[] getYoursubscription() {
    return yoursubscription;
}
public void setYoursubscription(String[] yoursubscription) {
    this.yoursubscription = yoursubscription;
}


public UploadProfile(){
    System.out.println("inside constructor");
    subscription=new ArrayList<String>();
    subscription.add("Politics");
    subscription.add("Sports");
    subscription.add("Editorial");
    subscription.add("Gadgets");
    subscription.add("Overdrive");
    }

public String[] getDefaultSubscription(){
    return new String [] {"Politics", "Sports"};
}
public List<String> getSubscription() {
    return subscription;
}
public void setSubscription(List<String> subscription) {
    this.subscription = subscription;
}


public String execute()throws Exception{
    System.out.println("inside execute");
    System.out.println(yoursubscription.toString()+"   "+subscription+"    "+defaultsubscription);
    if(fname!=null){
    return "profileuploaded";
    }else{
        return "error";

    }
}
public String display() {
    return NONE;
}



}