Question

我有一个Struts 2页面，其中有2个DisplayTag表，每个表都有一个List<T>。这个List<T>填充在代码隐藏中，并且可以长达几千个条目。在页面上，我可以选择其中一个表的行，然后按一个按钮将它们从一个表移动到另一个表。在最后按下另一个按钮以保存数据库中某个表的内容之前，可以多次执行此操作。我想通过AJAX在动作中完成这两件事。

userGroupEditmembers.jsp（为多余的空格道歉，在eclipse中使用块选择的残余）

<table>
    <tr>
        <td>
            <p class="collectionAlt">
                <s:text name="overview.groupMembers" />
            </p>
            <s:set name="groupMembers" value="groupMembers" scope="request" />
            <display:table name="groupMembers" uid="row" excludedParams="*" cellspacing="1" cellpadding="1">
                <%-- include localized messages for the table's banner --%>                     
                <%@ include file="/jsp/includesstruts2/displayTagBanner.jsp"%> 

                <display:column sortable="false" headerClass="listHeader">
                    <s:checkbox name="groupMemberOids" fieldValue="%{#attr.row.oid}"  theme="simple" />                                                       
                </display:column>                                                               
                <%-- User Name --%>
                <display:column property="userId" titleKey="label.user.userId" headerClass="listHeader" />                                                 

                <%-- User Name --%>
                <display:column property="name" titleKey="label.user.name" headerClass="listHeader" />                                                 

                <%-- Whether the User is archived --%>                                          
                <display:column titleKey="label.user.archived" headerClass="listHeader"         
                    class="iconColumn">                                                         
                    <s:if test="%{#attr.row.archived}">                                         
                        <img src="<s:url value='/images/checkedWarning.gif'/>" border="0" />    
                    </s:if>                                                                     
                </display:column>                                                               
            </display:table>                                                                    
        </td>                                                                                   
        <td>                                                                                    
            <%-- 'Remove Users from Group' button --%>                                          
            <input value="&gt;&gt;" type="button" id="removeUsersButton" /> <br />              
            <br />                                                                              
            <%-- The 'Refresh' button. Used to reload the issueTrackingSystemEditDialog.jsp --%>
            <input value="&lt;&lt;" type="button" id="addUsersButton" />                        
        </td>                                                                                   
        <td>                                                                                    
            <p class="collectionAlt">                                                           
                <s:text name="overview.nonGroupMembers" />                                      
            </p>                                                                                
            <s:set name="nonGroupMembers" value="nonGroupMembers" scope="request" />            

            <display:table name="nonGroupMembers" uid="row" excludedParams="*"                  
                cellspacing="1" cellpadding="1">                                                
                <%-- include localized messages for the table's banner --%>                     
                <%@ include file="/jsp/includesstruts2/displayTagBanner.jsp"%>                  

                <display:column sortable="false" headerClass="listHeader">                      
                    <s:checkbox name="nonGroupMemberOids" fieldValue="%{#attr.row.oid}"         
                        theme="simple" />                                                       
                </display:column>                                                               
                <%-- User Name --%>                                                             
                <display:column property="userId" titleKey="label.user.userId"                  
                    headerClass="listHeader" />                                                 

                <%-- User Name --%>                                                             
                <display:column property="name" titleKey="label.user.name"                      
                    headerClass="listHeader" />                                                 

                <%-- Whether the User is archived --%>                                          
                <display:column titleKey="label.user.archived" headerClass="listHeader"         
                    class="iconColumn">                                                         
                    <s:if test="%{#attr.row.archived}">                                         
                        <img src="<s:url value='/images/checkedWarning.gif'/>" border="0" />    
                    </s:if>                                                                     
                </display:column>                                                               
            </display:table>                                                                    
        </td>                                                                                   
    </tr>                                                                                       
</table>                                                                                        
<s:token />                                                                                     


<s:hidden name="oid" />                                                                         
<s:hidden name="version" />                                                                     
<s:hidden name="groupMembersJson" />                                                            
<s:hidden name="nonGroupMembersJson" />

UserGroupEditMembersAction.java：

private Integer oid;
private Integer version;

private List<UserView> groupMembers;

private List<UserView> nonGroupMembers;

private String groupMembersJson;

private String nonGroupMembersJson;

private Integer[] groupMemberOids;

private Integer[] nonGroupMemberOids;

private Boolean showArchived;

/**
 * method for DisplayUserGroupEdit action.
 * 
 * @return
 * @throws Exception
 */
public String display() throws Exception {
    if (showArchived == null) {
        showArchived = false;
    }
    UserService userService = (UserService) ServiceFactory.getInstance().createService(UserService.class);
    List<List<UserView>> usersForUserGroup = userService.getUsers(oid, showArchived);
    groupMembers = usersForUserGroup.get(0);
    nonGroupMembers = usersForUserGroup.get(1);
    groupMembersJson = serializeToJsonString(groupMembers);
    nonGroupMembersJson = serializeToJsonString(nonGroupMembers);

    return SUCCESS;
}

public String addMembers() throws Exception {
    groupMembers = (List<UserView>) deserializeFromJsonString(groupMembersJson);
    nonGroupMembers = (List<UserView>) deserializeFromJsonString(nonGroupMembersJson);
    UserService userService = (UserService) ServiceFactory.getInstance().createService(UserService.class);
    for (Integer userOid : nonGroupMemberOids) {
        UserView userview = userService.getUser(userOid);
        groupMembers.add(userview);
        for(int i = 0; i< nonGroupMembers.size(); i++){
            UserView view = nonGroupMembers.get(i);
            if(view.getOid().equals(userOid)){
                nonGroupMembers.remove(i);
                break;
            }
        }
    }
    groupMembersJson = serializeToJsonString(groupMembers);
    nonGroupMembersJson = serializeToJsonString(nonGroupMembers);
    return SUCCESS;
}

public String removeMembers() throws Exception {
    groupMembers = (List<UserView>) deserializeFromJsonString(groupMembersJson);
    nonGroupMembers = (List<UserView>) deserializeFromJsonString(nonGroupMembersJson);
    UserService userService = (UserService) ServiceFactory.getInstance().createService(UserService.class);
    for (Integer userOid : groupMemberOids) {
        UserView userview = userService.getUser(userOid);
        nonGroupMembers.add(userview);
        for(int i = 0; i< groupMembers.size(); i++){
            UserView view = groupMembers.get(i);
            if(view.getOid().equals(userOid)){
                groupMembers.remove(i);
                break;
            }
        }
    }
    groupMembersJson = serializeToJsonString(groupMembers);
    nonGroupMembersJson = serializeToJsonString(nonGroupMembers);
    return SUCCESS;
}

我遇到的问题是，当我将元素从一个List移动到另一个List时，我需要访问当前在表中使用的列表。因为Struts2操作是无状态的，所以我需要在两个操作之间保留这些列表。

我尝试将列表放在<s: hidden />块中，但无法轻易转换回来。
我目前的尝试是通过JSONUtil.serialize和JSONUtil.deserialize方法将它们序列化为JSON，但出于某种原因，将它们反序列化为List<HashMap>而不是List<T>。
我建议我的同事使用Session，但他担心性能损失。

处理此问题的最佳方法是什么？

Answer 1

行动链是正确的方法。我正在使用注释，所以代码看起来像这样。

@Action(
            value = "/loginAction",
            results = {
                    @Result(name = "car_user", type="chain", params = {"actionName", "getAllUserAction", "loginUser", "${loginUser}"}),

....................

其中loginUser是在loginAction类中具有setter getter的变量，而具有actionName getAllUserAction的chain attion类将在该类中具有setter getter的loginUser变量中接收它。

在Struts2中，如何在两个操作之间保留数据？

1 个答案: