如何将list对象中的属性从一个放入第二个动作

Question

我认为我的问题非常简单，但我正在尝试一周后才能完成这项工作。

我有一个MainAction，其中包含Processes列表，如下所示：

private List<Process> processes;

使用getter和setter

编辑或删除我有processForm.jsp和ProcessAction的流程。

所以我的问题是从列表中获取特殊进程的id到ProcessAction。

当我尝试这个时：

<s:hidden name="processes[%{#status.index}].id"/>

id在隐藏字段

中

<input type="hidden" name="processes[0].id" value="20" id="ShowMain_processes_0__id">

但未映射到操作

当我这样尝试时：

<s:hidden name="process.id" value="processes[%{#status.index}].id"/>

根本不起作用....

有人帮我怎么办？

这里有新的细节：

struts.xml中

<?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="tiles-default">

    <action name="ShowMain" class="com.goemon.smart.action.MainAction">
        <result type="tiles">mainForm</result>
    </action>

    <action name="Cancel" class="com.goemon.smart.action.MainAction">
        <result type="redirectAction">ShowMain</result>
    </action>

    <action name="ExecuteStartAction" class="com.goemon.smart.action.MainAction" method="executeStartCommand">
        <result name="success" type="redirectAction">ShowMain</result>
        <result name="input" type="redirectAction">ShowMain</result>
    </action>

    <action name="ExecuteStopAction" class="com.goemon.smart.action.MainAction" method="executeStopCommand">
        <result name="success" type="redirectAction">ShowMain</result>
        <result name="input" type="redirectAction">ShowMain</result>
    </action>

    <action name="DeleteProcess" class="com.goemon.smart.action.MainAction" method="deleteProcess">
        <result name="success" type="redirectAction">ShowMain</result>
    </action>

    <action name="ShowAction" class="com.goemon.smart.action.ProcessAction">
        <result type="tiles">actionForm</result>
    </action>

    <action name="CreateAction" class="com.goemon.smart.action.ProcessAction" method="createAction">
        <result name="success" type="redirectAction">ShowMain</result>
        <result name="error" type="redirectAction">ShowAction</result>
        <result name="input" type="redirectAction">ShowAction</result>
    </action>

    <action name="EditCommandAction" class="com.goemon.smart.action.ProcessAction" method="editAction">
        <result name="success" type="tiles">actionForm</result>
    </action>

    <action name="InsertDefault" class="com.goemon.smart.action.ProcessAction" method="insertDefaults">
        <result name="success" type="redirectAction">ShowMain</result>
    </action>

</package>

mainForm.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<%@ taglib uri="/struts-tags" prefix="s" %>

<div class="container">
<legend>
    <h1><s:text name="header.mainpage"/></h1>
</legend>

<s:iterator var="currentProcess" value="processes">
    <div class="jumbotron well col-lg-5 col-lg-offset-1">
        <s:form theme="bootstrap" cssClass="bs-example form-horizontal">

            <div class="btn-toolbar pull-right">
                <s:a action="DeleteProcess">
                    <button type="button" class="btn btn-default" aria-label="Left Align">
                        <span class="glyphicon glyphicon-trash" aria-hidden="true"></span>
                    </button>
                </s:a>
                <s:a action="EditCommandAction">
                    <button type="button" class="btn btn-default" aria-label="Left Align">
                        <span class="glyphicon glyphicon-cog" aria-hidden="true"></span>
                    </button>
                </s:a>
            </div>

            <s:hidden name="id" value="%{#currentProcess.id}"/>

            <h2>
                <s:text name="%{#currentProcess.name}"/>
            </h2>

            <div class="btn-toolbar pull-right">
                <s:submit key="btn.start" action="ExecuteStartAction"
                          cssClass="btn btn-primary btn-lg btn-success"/>
                <s:submit key="btn.stop" action="ExecuteStopAction"
                          cssClass="btn btn-primary btn-lg btn-danger"/>
            </div>
        </s:form>
    </div>
</s:iterator>
<s:debug/>

processForm.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<%@ taglib uri="/struts-tags" prefix="s" %>

<div class="col-lg-6 col-lg-offset-3 well">
<div class="col-lg-12">
    <s:form theme="bootstrap" cssClass="bs-example form-horizontal">

        <legend>
            <s:text name="header.manage"/>
        </legend>

        <s:hidden name="initial"/>
        <s:textfield name="process.name" key="lbl.process.name" cssClass="col-lg-12"/>
        <s:textfield name="process.host" key="lbl.process.host" cssClass="col-lg-12"/>

        <div class="col-lg-11 pull-right">
            <s:iterator var="counter" begin="0" end="2">
                <div class="col-lg-12">
                    <s:hidden name="process.commands[%{#counter}].id"/>

                    <s:select key="lbl.command.type" list="commandTypeValues"
                              name="process.commands[%{#counter}].commandType" headerKey=""
                              headerValue="%{commandTypeValues[#counter]}"/>

                    <s:textfield name="process.commands[%{#counter}].command"
                                 key="lbl.process.command"/>
                </div>
            </s:iterator>
        </div>

        <s:textfield name="process.user" key="lbl.process.user" cssClass="col-lg-12"/>
        <s:textfield name="process.password" key="lbl.process.password" cssClass="col-lg-12"/>

        <s:submit key="btn.create" action="CreateAction" cssClass="btn btn-primary pull-right"/>
        <s:submit key="btn.cancel" action="Cancel" cssClass="btn btn-primary pull-right"/>

        <s:debug />
    </s:form>
</div>

ProcessAction.java

package com.goemon.smart.action;

import com.goemon.smart.model.CommandType;
import com.goemon.smart.model.Process;
import com.goemon.smart.service.ProcessService;
import com.goemon.smart.util.DefaultingUtil;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.Preparable;
import org.springframework.beans.factory.annotation.Autowired;

/**
 * Created by John on 4/4/15.
 */
public class ProcessAction extends ActionSupport implements Preparable {

@Autowired
private ProcessService processService;

@Autowired
private DefaultingUtil defaultingUtil;

private Process process;

private Long id;

private CommandType[] commandTypeValues = CommandType.values();

@Override
public void prepare() throws Exception {
}

public String execute() {
    return SUCCESS;
}

public String createAction() {
    try {
        processService.saveAction(process);
    } catch (Exception e) {
        return INPUT;
    }
    return SUCCESS;
}

public String editAction() {
    return SUCCESS;
}

public String insertDefaults() {
    try {
        Process ambiLight = defaultingUtil.ambiLightDefault();
        processService.saveAction(ambiLight);
    } catch (Exception e) {
        return SUCCESS;
    }
    return SUCCESS;
}

public Process getProcess() {
    return process;
}

public void setProcess(Process process) {
    this.process = process;
}

public CommandType[] getCommandTypeValues() {
    return commandTypeValues;
}

public void setCommandTypeValues(CommandType[] commandTypeValues) {
    this.commandTypeValues = commandTypeValues;
}

public Long getId() {
    return id;
}

public void setId(Long id) {
    this.id = id;
}
}

Answer 1

迭代时，您不需要状态对象来访问字段。 Struts将当前列表项放在值堆栈的顶部，这样就足够了：

<s:hidden name="process.id" value="%{id}"/>

或者，您可以在迭代器标记中指定变量名称：

<s:iterator var="currentProcess" value="processes">
    <s:hidden name="process.id" value="%{#currentProcess.id}"/>
</s:iterator>

请注意，name属性必须与ProcessAction中的字段匹配。因此，如果name="process.id"需要字段process，则必须初始化类型Process，在Struts插入值之前，您将获得NullpointerException。

如果您使用<s:hidden/>，请确保使用<s:submit>标记，就像您为＆＃34; ExecuteStartAction＆＃34;而不是<button>。

如果您想使用链接而不是表单按钮，请使用：

<s:url var="editUrl" action="EditCommandAction">
    <s:param name="id" value="%{#currentProcess.id}" />
</s:url>
<s:a href="%{editUrl}">...</s:a>

然后，您可以使用CSS来设置您想要的链接样式。

但正如亚历山大M已经说过的那样，不要混合按钮和链接。