以XML形式访问远程接口获得数据

JDK提供了供我们访问url获得数据的类，核心类主要是URL,URLConnection等（详见JDK API）
下面以XML形式实现两者通信
Servlet端发送信息：

protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        // TODO Auto-generated method stub
        resp.setCharacterEncoding("utf-8");
        PrintWriter print= resp.getWriter();
        String s = "<?xml version='1.0' encoding='utf-8'?>
                                    <web-shhzs>
                                       <return-param>
                                          <return-no>0</return-no>
                                          <return-text>执行正常</return-text>
                                        </return-param>
                                        <ptfp>
                                          <kpxsje>123456789</kpxsje>
                                        </ptfp>
                                    </web-shhzs>";
        print.write(s);
        print.flush();
        print.close();
    }

protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		resp.setCharacterEncoding("utf-8");
		PrintWriter print= resp.getWriter();
		String s = "<?xml version='1.0' encoding='utf-8'?>
                                    <web-shhzs>
                                       <return-param> 
                                          <return-no>0</return-no>
                                          <return-text>执行正常</return-text>
                                        </return-param>
                                        <ptfp>
                                          <kpxsje>123456789</kpxsje>
                                        </ptfp>
                                    </web-shhzs>";
		print.write(s);
		print.flush();
		print.close();
	}

获得访问返回信息，以字符串返回：

    public static String getXML(String sh,String type,String date) throws IOException{
        StringBuffer urlStr = new StringBuffer("http://localhost:8888/Hello/getDom.do");
//      urlStr.append("?param1=").append(sh)
//            .append("&param2=").append(type)
//            .append("&param3=").append(date);
        URL url = new URL(urlStr.toString());
        URLConnection URLconnection = url.openConnection();
        HttpURLConnection httpConnection = (HttpURLConnection)URLconnection;
        int responseCode = httpConnection.getResponseCode();
//      FileOutputStream fos=new FileOutputStream("d://line.txt",true);
//      DataOutputStream out=new DataOutputStream(fos);
        StringBuffer totalXML = new StringBuffer("");
        if(responseCode == HttpURLConnection.HTTP_OK){
            InputStream httpStream = httpConnection.getInputStream();
            BufferedReader bufferReader = new BufferedReader(new InputStreamReader(httpStream));
            String currLine = "";
            while((currLine=bufferReader.readLine())!=null){
//              out.writeBytes(new   String(currLine.getBytes(),"utf-8"));
//              out.writeBytes("\r\n");
                totalXML.append(currLine);
            }
        }
//      fos.close();
//      out.close();
        return totalXML.toString();
    }

	public static String getXML(String sh,String type,String date) throws IOException{
		StringBuffer urlStr = new StringBuffer("http://localhost:8888/Hello/getDom.do");
//		urlStr.append("?param1=").append(sh)
//			  .append("&param2=").append(type)
//			  .append("&param3=").append(date);
		URL url = new URL(urlStr.toString());
		URLConnection URLconnection = url.openConnection();
		HttpURLConnection httpConnection = (HttpURLConnection)URLconnection;
		int responseCode = httpConnection.getResponseCode();
//		FileOutputStream fos=new FileOutputStream("d://line.txt",true);   
//	    DataOutputStream out=new DataOutputStream(fos); 
	    StringBuffer totalXML = new StringBuffer("");
		if(responseCode == HttpURLConnection.HTTP_OK){
			InputStream httpStream = httpConnection.getInputStream();
			BufferedReader bufferReader = new BufferedReader(new InputStreamReader(httpStream));
			String currLine = "";
			while((currLine=bufferReader.readLine())!=null){
//				out.writeBytes(new   String(currLine.getBytes(),"utf-8"));   
//	            out.writeBytes("\r\n");   
				totalXML.append(currLine);
			}
		}
//		fos.close();   
//      out.close();   
		return totalXML.toString();
	}

用DOM4J解析XML获得相应信息封装为Map

public static Map getFpxx(String text){

    Map map = new HashMap();
    Document document;
    try {
                 //dom4j解析字符串为xml
    document = DocumentHelper.parseText(text);
        Element root = document.getRootElement();
        Element e1 = root.element("return-param");
        if(null!=e1){
             if(null!=e1){
                 String state = e1.element("return-text").getStringValue();
                 System.out.println(state);
                 map.put("state", state);

             }
             Element e2 = root.element("ptfp");
             if(null!=e2){
                 String kpxsje = e2.element("kpxsje").getStringValue();
                 System.out.println(kpxsje);
                 map.put("result", kpxsje);
             }
         }
    } catch (DocumentException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        logger.error("字符串转换为xml时出错");
    }
    return map;
}