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1、封装XML报文对象

博主在调第三方接口时，经常需要封装XML去请求第三方的数据，在Web开发时，需要经常用到，因此也打算写篇文章记录下本人在思考和寻求答案的过程。

1-1 XML的一些基本常识

一般在参考一些API的文档时，JAVA开发一般是根据特定的API要求去对数据进行封装，在此，我将采用举例的方式来说明，已经应用场景。在封装XML对象时，首先我们得了解封装XML对象试用方式，一般采取Class类注解的形式去实现。如@XmlType、@XmlAccessorType、@XmlRootElement、 @XmlElement等。

@XmlType(propOrder ={ "Header", "MessageType", "Message" }) // 指定序列成的xml节点顺序

@XmlAccessorType(value = XmlAccessType.FIELD) // 访问类型改为字段

@XmlRootElement(name = "AmazonEnvelope")//封装XML对象的根节点

1-2 封装XML针对某些特定API请求参数。这里以对接亚马逊的某些接口举例

以下为我举例加入某接口需要对参数封装XML：

/*







* 	<?xml version="1.0" encoding="UTF-8"?>







*	<AmazonEnvelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="amzn-envelope.xsd">







*		<Header>







*			<DocumentVersion>1.02</DocumentVersion>







*			<MerchantIdentifier>A23G8Q8ZIKBK8C</MerchantIdentifier>







*		</Header>







*		<MessageType>ProcessingReport</MessageType>







*		<Message>







*			<MessageID>1</MessageID>







*			<ProcessingReport>







*				<DocumentTransactionID>57320017876</DocumentTransactionID>







*				<StatusCode>Complete</StatusCode>







*				<ProcessingSummary>







*					<MessagesProcessed>15</MessagesProcessed>







*					<MessagesSuccessful>13</MessagesSuccessful>







*					<MessagesWithError>2</MessagesWithError>







*					<MessagesWithWarning>0</MessagesWithWarning>







*				</ProcessingSummary>







*				<Result>







*					<MessageID>3</MessageID>







*					<ResultCode>Error</ResultCode>







*					<ResultMessageCode>25</ResultMessageCode>







*					<ResultDescription>We are unable to process the XML feed because one or more items are invalid. Please re-submit the feed.</ResultDescription>







*				</Result>







*				<Result>







*					<MessageID>4</MessageID>







*					<ResultCode>Error</ResultCode>







*					<ResultMessageCode>25</ResultMessageCode>







*					<ResultDescription>We are unable to process the XML feed because one or more items are invalid. Please re-submit the feed.</ResultDescription>







*				</Result>







*			</ProcessingReport>







*		</Message>







*	</AmazonEnvelope>















*/

如果看到这种XML格式，去封装请求对象如何封装呢？

我们如果有了解过XML这种语言就知道，XML可以理解为一颗树，有父子根节点构成。其实Spring 内部去解析XML时，也是根据这种特性去解析的。因为我们最原始MVC 需要大量的配置XML 注入bean。以及配置事物等等。我们通过分析可以发现，外部根节点为AmazonEnvelope，子节点Header、MessageType、Message，然后Message节点下又有子节点MessageID、ProcessingReport。依次类推，可以构造AmazonEnvelope大对象，然后以此为根节点建造子节点对象，这里举例两个如下：

package com.aukey.supply.chain.domain.test;















import javax.xml.bind.annotation.XmlAccessType;







import javax.xml.bind.annotation.XmlAccessorType;







import javax.xml.bind.annotation.XmlElement;







import javax.xml.bind.annotation.XmlRootElement;







import javax.xml.bind.annotation.XmlType;















@XmlType(propOrder =







{ "Header", "MessageType", "Message" }) // 指定序列成的xml节点顺序







@XmlAccessorType(value = XmlAccessType.FIELD) // 访问类型改为字段







@XmlRootElement(name = "AmazonEnvelope")







public class AmazonEnvelope {







	 @XmlElement







	 private Header Header;//构造头部















	 @XmlElement







	 private String MessageType;























	 @XmlElement







	 private Message Message;























	public Header getHeader() {







		return Header;







	}























	public void setHeader(Header header) {







		Header = header;







	}























	public String getMessageType() {







		return MessageType;







	}























	public void setMessageType(String messageType) {







		MessageType = messageType;







	}























	public Message getMessage() {







		return Message;







	}























	public void setMessage(Message message) {







		Message = message;







	}







}

package com.aukey.supply.chain.domain.test;















import javax.xml.bind.annotation.XmlAccessType;







import javax.xml.bind.annotation.XmlAccessorType;







import javax.xml.bind.annotation.XmlElement;







import javax.xml.bind.annotation.XmlType;















@XmlType(propOrder =







{ "MessageID", "ProcessingReport"}) // 指定序列成的xml节点顺序







@XmlAccessorType(value = XmlAccessType.FIELD) // 访问类型改为字段







public class Message {















	@XmlElement







	private String MessageID;















	@XmlElement







	private ProcessingReport ProcessingReport;















	public String getMessageID() {







		return MessageID;







	}















	public void setMessageID(String messageID) {







		MessageID = messageID;







	}















	public ProcessingReport getProcessingReport() {







		return ProcessingReport;







	}















	public void setProcessingReport(ProcessingReport processingReport) {







		ProcessingReport = processingReport;







	}















}

对象封装完成之后，API一般需要请求参数，因此我们建完实体对象后，需要按照不同节点要求赋值，示例如下：

/**







	 * 构造XML对象 将节点数据组装成一个XML大对象







	 * @return







	 */







	public static AmazonEnvelope createXmlObject() 







	{







		AmazonEnvelope amazonEnvelope =new AmazonEnvelope();















		//子级节点1







		Header header =new Header();







		header.setDocumentVersion("1.02");







		header.setMerchantIdentifier("A23G8Q8ZIKBK8C");







		//赋值子级节点1







		amazonEnvelope.setHeader(header);















		//子级节点1







		String messageType="ProcessingReport";







		//赋值子级节点1







		amazonEnvelope.setMessageType(messageType);















		//子级节点1







		Message message =new Message();







		//赋值子级节点2







		message.setMessageID("1");















		//子级节点2







		ProcessingReport processingReport=new ProcessingReport();















		//赋值子级节点2







		processingReport.setDocumentTransactionID("57320017876");







		//赋值子级节点2







		processingReport.setStatusCode("Complete");















		//子级节点3







		ProcessingSummary processingSummary =new ProcessingSummary();







		//赋值子级节点3







		processingSummary.setMessagesProcessed("15");







		//赋值子级节点3







		processingSummary.setMessagesSuccessful("13");







		//赋值子级节点3







		processingSummary.setMessagesWithError("2");







		//赋值子级节点3







		processingSummary.setMessagesWithWarning("0");















		//子级节点3







		List<Result> results=new ArrayList<>();







		Result result =new Result();







		//赋值子级节点4







		result.setMessageID("3");







		//赋值子级节点4







		result.setResultCode("Error");







		//赋值子级节点4







		result.setResultDescription("25");







		//赋值子级节点4







		result.setResultMessageCode("We are unable to process the XML feed because one or more items are invalid. Please re-submit the feed.");















		//赋值子级节点3







		results.add(result);























		//赋值子级节点2







		processingReport.setResult(results);















		//赋值子级节点2







		processingReport.setProcessingSummary(processingSummary);















		//赋值子级节点2







		message.setProcessingReport(processingReport);















		//赋值子级节点1







		amazonEnvelope.setMessage(message);















		return amazonEnvelope;







	}

对象赋值完成后，需要把当前的XML对象封装整个XML，一般设置字符编码等。 并且组装成一个String 这里JAXBContext文本对象来完成：

/**







	 * 构造XML 报文对象







	 * @param amazonEnvelope







	 * @return







	 */







	public static String createXml(AmazonEnvelope amazonEnvelope) 







	{







		JAXBContext context;







		try {







			context = JAXBContext.newInstance(amazonEnvelope.getClass());







			Marshaller marshaller = context.createMarshaller();







			marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);







			marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");







			StringWriter writer = new StringWriter();







			marshaller.marshal(amazonEnvelope, writer);







			String xml = writer.toString();







			return xml;







		} catch (JAXBException e) {







			e.printStackTrace();







		}







		return "";







	}

封装XML完成之后，就可以调取第三方的API并DOM解析返回了，这里说明为了方便，将请求对象和解析对象置为同一个。下面看主类全套调用逻辑：

package com.aukey.supply.chain.web.test;















import java.io.StringReader;







import java.io.StringWriter;







import java.util.ArrayList;







import java.util.HashMap;







import java.util.List;







import java.util.Map;















import javax.xml.bind.JAXBContext;







import javax.xml.bind.JAXBException;







import javax.xml.bind.Marshaller;







import javax.xml.bind.Unmarshaller;















import org.dom4j.Document;







import org.dom4j.DocumentException;







import org.dom4j.DocumentHelper;







import org.dom4j.Element;















import com.alibaba.fastjson.JSON;







import com.aukey.supply.chain.domain.test.AmazonEnvelope;







import com.aukey.supply.chain.domain.test.Header;







import com.aukey.supply.chain.domain.test.Message;







import com.aukey.supply.chain.domain.test.ProcessingReport;







import com.aukey.supply.chain.domain.test.ProcessingSummary;







import com.aukey.supply.chain.domain.test.Result;







import com.aukey.supply.chain.utils.Md5Utils;







import com.aukey.supply.chain.utils.XMLPostUtils;















public class TestAnalyzeXml {







	public static void main(String[] args) 







	{







		//组装请求报文XML对象







		AmazonEnvelope amazonEnvelope =createXmlObject();















		//构造XML文本







		String xml= createXml(amazonEnvelope);















        try 







        {







        	//封装请求报文 然后发送HTTP请求 然后将返回XML字符串 进行解析对应XML格式的节点对象 然后获取对应的节点数据







        	String urlStr = "http://info.edaeu.com/Api/";







        	String token="";







        	String md5;







            try {







                md5 = Md5Utils.ChangeMd5(token.substring(0, 16) + xml + token.substring(16, 32));







            } catch (Exception e) {







                md5 = "";







            }







            String httpPost = XMLPostUtils.httpPost(xml, urlStr+"/"+md5);







            JAXBContext getcontext = JAXBContext.newInstance(amazonEnvelope.getClass());







            Unmarshaller unmarshaller = getcontext.createUnmarshaller();







            StringReader reader = new StringReader(httpPost);







			Object object=(AmazonEnvelope)unmarshaller.unmarshal(reader);







		} catch (JAXBException e1) {







			e1.printStackTrace();







		}















		try{







			Document document = DocumentHelper.parseText(xml);







			// 通过document对象获取根节点







		    Element root = document.getRootElement();







		    Element message = root.element("Message");







		    Element processingReport = message.element("ProcessingReport");







		    @SuppressWarnings("unchecked")







		    List<Element> results = processingReport.elements("Result");







		    List<Map<String, Object>> mapResultList=new ArrayList<Map<String,Object>>();







		    for (Element element : results) 







		    {







				Map<String, Object> map =new HashMap<String, Object>();







				map.put("MessageID",element.element("MessageID").getTextTrim());







				map.put("ResultCode", element.element("ResultCode").getTextTrim());







				map.put("ResultMessageCode",element.element("ResultMessageCode").getTextTrim());







				map.put("ResultDescription", element.element("ResultDescription").getTextTrim());







				mapResultList.add(map);







			}







		    System.out.println(JSON.toJSONString(mapResultList));















		} catch (DocumentException e) {







			e.printStackTrace();







		}































	}































}

以上获取完数据，差不多解析调用就完成了。整个封装XML并调用API，以及返回解析API返回的XML就完成了！

福利（附带Http请求XML封装工具类以及MD5加密类）：

package com.aukey.supply.chain.utils;















import java.io.ByteArrayOutputStream;







import java.io.InputStream;







import java.io.OutputStream;







import java.io.StringReader;







import java.net.HttpURLConnection;







import java.net.URL;















import javax.xml.bind.JAXBContext;







import javax.xml.bind.Unmarshaller;







import javax.xml.parsers.SAXParserFactory;







import javax.xml.transform.Source;







import javax.xml.transform.sax.SAXSource;















import org.xml.sax.InputSource;







import org.xml.sax.XMLReader;















public class XMLPostUtils







{















    public static String httpPost(String xml, String urlStr)







    {







        try







        {







            URL url = new URL(urlStr);







            // 建立http连接







            HttpURLConnection conn = (HttpURLConnection) url.openConnection();







            // 设置允许输出







            conn.setDoOutput(true);















            conn.setDoInput(true);















            // 设置不用缓存







            conn.setUseCaches(false);







            // 设置传递方式







            conn.setRequestMethod("POST");







            // 设置维持长连接







            conn.setRequestProperty("Connection", "Keep-Alive");







            // 设置文件字符集:







            conn.setRequestProperty("Charset", "UTF-8");







            // 转换为字节数组







            byte[] data = xml.getBytes();







            // 设置文件长度







            conn.setRequestProperty("Content-Length", String.valueOf(data.length));







            // 设置文件类型:







            conn.setRequestProperty("contentType", "text/xml");







            // 开始连接请求







            conn.connect();







            OutputStream out = conn.getOutputStream();







            // 写入请求的字符串







            out.write(data);







            out.flush();







            out.close();















            // 请求返回的状态







            if (conn.getResponseCode() == 200)







            {







                // 请求返回的数据







                InputStream in = conn.getInputStream();







                try







                {







                    ByteArrayOutputStream s = new ByteArrayOutputStream();







                    int length = 0;







                    byte[] buffer = new byte[1024 * 1024];







                    while ((length = in.read(buffer)) != -1)







                    {







                        s.write(buffer, 0, length);







                    }







                    return s.toString("UTF-8");















                }







                catch (Exception e1)







                {







                    e1.printStackTrace();







                }







                finally







                {







                    in.close();







                }







            }







            else







            {







            }















        }







        catch (Exception e)







        {







            e.printStackTrace();















        }







        return null;







    }















    public static <T> T convertXmlToJavaBean(String xml, Class<T> t) throws Exception







    {







        T obj;







        JAXBContext context = JAXBContext.newInstance(t);







        StringReader stringReader = new StringReader(xml);







        SAXParserFactory sax = SAXParserFactory.newInstance();







        sax.setNamespaceAware(false);// 设置忽略明明空间







        XMLReader xmlReader = sax.newSAXParser().getXMLReader();







        Source source = new SAXSource(xmlReader, new InputSource(stringReader));







        Unmarshaller unmarshaller = context.createUnmarshaller();







        obj = (T) unmarshaller.unmarshal(source);







        return obj;







    }















}

package com.aukey.task.centerwarehouse.utils;















import java.security.MessageDigest;







import java.security.NoSuchAlgorithmException;















public class Md5Utils







{







    public static String ChangeMd5(String password)







    {















        try







        {







            // 得到一个信息摘要器







            MessageDigest digest = MessageDigest.getInstance("md5");







            byte[] result = digest.digest(password.getBytes());







            StringBuffer buffer = new StringBuffer();







            // 把每一个byte 做一个与运算 0xff;







            for (byte b : result)







            {







                // 与运算







                int number = b & 0xff;// 加盐







                String str = Integer.toHexString(number);







                if (str.length() == 1)







                {







                    buffer.append("0");







                }







                buffer.append(str);







            }















            // 标准的md5加密后的结果







            return buffer.toString();







        }







        catch (NoSuchAlgorithmException e)







        {







            e.printStackTrace();







            return "";







        }















    }







}