关于Struts2 返回XML的有关问题

关于Struts2 返回XML的问题
????? </action>
里面包含了Action的所有属性,还有Locale等信息. 可以在浏览器里输入http://localhost:8080/XXX/XXX/XmlModel.action来看.

2. 为了定制自己想要的XML,我们可以输入参数来输出自己想要的Action的某个属性(属性可以是一个List).
????? <action name="XmlModel" type="xslt">
????????????????? <param name=”exposedValue”>modelList</param>
??????????? </result>
????? </action>

3. 如果有多于一个属性呢.加个大括号围起来
????? <action name="XmlModel" type="xslt">
????????????????? <param name=”exposedValue”>{modelList, type}</param>
??????????? </result>
????? </action>

4. 以上三个方法都是由Action 来控制生成格式.那么对于我们这种控制欲很强的人来说并不满足,最好是由我们自己来定义生成样子.那么这时我们就要做的就是在属性里生成一个 org.w3c.dom.Document属性.注意:不要用org.dom4j.Document类.要不会出现转化错误,死得很惨.
????? <action name="XmlModel" type="xslt">
??????????? <param name="exposedValue">xmlDoc</param>
????? </result>
????? </action>
上面的xmlDoc就是 Action里的org.w3c.dom.Document类型.

5. 我只会用并且非要用org.dom4j.Document类怎么办? 那就在最后转化成 org.w3c.dom.Document:

import java.io.ByteArrayInputStream;import java.io.IOException;import javax.xml.parsers.DocumentBuilderFactory;import javax.xml.parsers.ParserConfigurationException;import org.xml.sax.SAXException;public class XmlUtil {private XmlUtil() {}public static org.w3c.dom.Document XmlString2W3cDom(String xml)throws SAXException, IOException, ParserConfigurationException {byte[] byteArray = xml.getBytes("UTF-8");ByteArrayInputStream baos = new ByteArrayInputStream(byteArray);DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();org.w3c.dom.Document doc = factory.newDocumentBuilder().parse(baos);return doc;}public static org.dom4j.Document W3c2Dom4j(org.w3c.dom.Document doc) {if (doc == null) {return (null);}org.dom4j.io.DOMReader xmlReader = new org.dom4j.io.DOMReader();return (xmlReader.read(doc));}}
Action里加上一句: xmlDoc = Xmlutil.XmlString2W3cDom(dom4jDoc.asXML());
上面的xmlDoc就是 Action里的org.w3c.dom.Document类型.

6. 用org.dom4j.dom.DOMDocumentFactory()来建立 Document.而不要用DocumentHelper.createDocument()来产生.最后直接cast一下.
public String execute() throws UnsupportedEncodingException, ParserConfigurationException, SAXException, IOException {InfoCpuService cpuSvc = null;cpuSvc = (InfoCpuService) ServiceLocator.getInstance().getService(InfoCpuService.class);modelList = cpuSvc.getModels(prodBrand);log.info(ReflectionToStringBuilder.toString(this));org.dom4j.Document dom4jDoc = new org.dom4j.dom.DOMDocumentFactory().createDocument();Element root = dom4jDoc.addElement("root");root.addAttribute("prodType", "CPU");for (Object o : modelList) {root.addElement("model").addAttribute("name", (String) o);}//xmlDoc = XmlUtil.XmlString2W3cDom(doc.asXML());xmlDoc = (Document) dom4jDoc;HttpServletResponse response = ServletActionContext.getResponse();response.setContentType("text/xml;charset=UTF-8");response.setHeader("Cache-Control", "no-cache");return SUCCESS;}
其中三句代码是为了防止生成中文乱码
?? HttpServletResponse response = ServletActionContext.getResponse();
?? response.setContentType("text/xml;charset=UTF-8");
?? response.setHeader("Cache-Control", "no-cache");

7. 在action中返回类型最好设置为import org.w3c.dom.Document;
private Document retXML;
配置格式为：
Java代码
<action?name="XmlModel"?class="com.XmlModelAction"> ?? ???????????<result?name="success"?type="xslt"> ?? ?????????????????<param?name=”exposedValue”>retXML</param> ?? ???????????</result> ?? ?</action>??