socket短连接，数据交互报文采用XML形式

 socket 服务端一直等待客户端

  public void threadServer() {
        // TODO Auto-generated method stub
        class ServerThread extends Thread {
            Socket socket = null;

            public ServerThread(Socket socket) {
                this.socket = socket;
            }

            public void run() {
                InputStream inputStream = null;
                OutputStream outputStream = null;
                try {
                    // 4.获取输入流，并读取服务器端的响应信息
                    inputStream = socket.getInputStream();
                    //封装数据写给服务器端
                    outputStream = socket.getOutputStream();
                    //  创建文件输出流，方便从socket读取的数据写入文件
                    byte[] buf = new byte[1024];
                    int readb = 0;
                    while ((readb = inputStream.read(buf)) != -1) {
                        String str = new String(buf, 0, readb, "GBK");
                        System.out.println("接收数据：" + str);
                        // 数据处理
                           String result = "测试";
                        // 转换编码方式
                        byte[] b = result.getBytes("GBK");
                        long len = b.length;
                        String length = String.format("%05d", len);
                        result = length + result;
                        byte[] bt = result.getBytes("GBK");
                        System.out.println("写入数据：" + result);
                        //写数据
                        outputStream.write(bt);
                        outputStream.flush();
                    }
                    System.out.println("服务器端接受完毕!");
                } catch (IOException e) {
                    e.printStackTrace();
                } finally {
                    try {
                        inputStream.close();
                        outputStream.close();
                        socket.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
        try {
            //1.创建服务器端ServerSocket对象，指定端口
            ServerSocket serverSocket = new ServerSocket(SysConstant.serverPort);
            Socket socket = null;
            System.out.println("服务器等待客户端的连接");
            //2.调用accept()监听（即等待客户端的连接）
            while (true) {
                socket = serverSocket.accept();
                //创建一个新线程
                ServerThread serverThread = new ServerThread(socket);
                serverThread.start();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

document 创建xml报文

   
    public static String createElement(JSonObject obj) {
        try {
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            TransformerFactory transformerFactory = TransformerFactory.newInstance();
            Transformer transformer = transformerFactory.newTransformer();
            //设置编码格式
            transformer.setOutputProperty(OutputKeys.ENCODING, "GBK");
            
            // 创建解析工厂
            documentBuilderFactory factory = documentBuilderFactory.newInstance();
            documentBuilder documentBuilder = factory.newdocumentBuilder();
            document document = documentBuilder.newdocument();
            document.setXmlStandalone(true);
            Element parent = document.createElement("ONEKEY");
            document.appendChild(parent);
            Element HEAD = document.createElement("HEAD");
            parent.appendChild(HEAD);
            // 返回代码
            Element RESULT_CODE = document.createElement("RESULT_CODE");
            RESULT_CODE.setTextContent("ok");
            // 返回信息
            Element RESULT_MSG = document.createElement("RESULT_MSG");
            RESULT_MSG.setTextContent("内容");
          
            HEAD.appendChild(RESULT_CODE);
            HEAD.appendChild(RESULT_MSG);
            DOMSource source = new DOMSource(document);
            transformer.transform(source, new StreamResult(bos));
            String result = bos.toString("GBK");
            return result ;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

 因公司需求与中行对接写的记录一下