一.使用URlConnection
//传入的数据为xml格式字符串
public static String sendPosts(String url, String param) throws DocumentException { System.out.println("=========发送报文=========="+"\n"+Xmlutil.getxml()); PrintWriter out = null; BufferedReader in = null; String result = ""; try { URL realUrl = new URL(url); // 打开和URL之间的连接 URLConnection conn = realUrl.openConnection(); // 设置通用的请求属性 conn.setRequestProperty("accept", "*/*"); conn.setRequestProperty("connection", "Keep-Alive"); conn.setRequestProperty("user-agent","Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); // 发送POST请求必须设置如下两行 conn.setDoOutput(true); conn.setDoInput(true); // 获取URLConnection对象对应的输出流 out = new PrintWriter(conn.getOutputStream()); // 发送请求参数 out.print(param); // flush输出流的缓冲 out.flush(); // 定义BufferedReader输入流来读取URL的响应 in = new BufferedReader( new InputStreamReader(conn.getInputStream())); String line; while ((line = in.readLine()) != null) { result += line; } } catch (Exception e) { System.out.println("发送 POST 请求出现异常!"+e); e.printStackTrace(); } //使用finally块来关闭输出流、输入流 finally{ try{ if(out!=null){ out.close(); } if(in!=null){ in.close(); } } catch(IOException ex){ ex.printStackTrace(); } } System.out.println(); System.out.println("=========响应报文=========="+"\n"+xmlprint(result)); return result; }
二.使用HTTPURLConnection(为URLConnection的子类)
public String Post(){ try { Xmlutil xml=new Xmlutil(); String xmlstr=xml.getxml(); System.out.println("==========发送报文============"+"\n"+xmlstr); // 创建url资源 URL url = new URL(url); // 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 = xmlstr.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(); System.out.println(conn.getResponseCode()); // 请求返回的状态 if (conn.getResponseCode() == 200) { System.out.println("连接成功"); // 请求返回的数据 InputStream in = conn.getInputStream(); String a = null; try { byte[] data1 = new byte[in.available()]; in.read(data1); // 转成字符串 a = new String(data1); System.out.println("========================响应报文========================"+"\n"+xmlprint(a)); return a; } catch (Exception e1) { // TODO Auto-generated catch block e1.printStackTrace(); } } else { System.out.println("no++"); } } catch (Exception e) { } return null; }
三.使用HTTPClient(最简洁的方式)
//使用httpclient进行http通信(采用HttpClient4.3以上版本) public String sendXMLDataByPost(String url, String xmlData) throws Exception { System.out.println("==================发送报文================="+"\n"+Xmlutil.getxml()); //1.创建httpclient对象 HttpClient httpclient=HttpClients.createDefault(); //2.创建POST请求 HttpPost post = new HttpPost(url); //3.添加http头信息 // post.addHeader("Content-Type", "text/xml;charset=UTF-8"); //4.创建消息实体 StringEntity stringEntity=new StringEntity(xmlData,"utf-8"); //解决中文乱码问题 stringEntity.setContentEncoding("utf-8"); //5.向post请求中添加消息实体 post.setEntity(stringEntity); //手动读取响应 // HttpResponse response=httpclient.execute(post); // HttpEntity httpEntity=response.getEntity(); // String result=EntityUtils.toString(httpEntity, "utf-8"); //响应器处理器 // ResponseHandler<String> responseHandler= new ResponseHandler<String>() { // // @Override // public String handleResponse(HttpResponse response) // throws ClientProtocolException, IOException { // // int status=response.getStatusLine().getStatusCode(); // // if(status>=200 && status<300){ // HttpEntity entity=response.getEntity(); // //三目运算符 // return entity != null ? EntityUtils.toString(entity) : null; // }else{ // throw new ClientProtocolException("Unexpected response status: " + status); // } // // } // // }; //自动读取响应 ResponseHandler<String> responseHandler= new BasicResponseHandler(); String result=httpclient.execute(post, responseHandler); System.out.println("==================响应报文================="+"\n"+xmlprint(result)); return result; }
关于响应内容可以有三种处理方式:EntityUtils、ResponseHandler、BasicResponseHandler