本文主要是介绍Android网络HttpURLConnection和HttpClient，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
1.概念
HTTP 协议可能是现在 Internet 上使用得最多、最重要的协议了，越来越多的 Java 应用程序需要直接通过 HTTP 协议来访问网络资源。在 JDK 的 java.net 包中已经提供了访问 HTTP 协议的基本功能：HttpURLConnection。但是对于大部分应用程序来说，JDK 库本身提供的功能还不够丰富和灵活。
除此之外，在Android中，androidSDK中集成了Apache的HttpClient模块，用来提供高效的、最新的、功能丰富的支持 HTTP 协议工具包，并且它支持 HTTP 协议最新的版本和建议。使用HttpClient可以快速开发出功能强大的Http程序。
2.区别
HttpClient是个很不错的开源框架，封装了访问http的请求头，参数，内容体，响应等等，
HttpURLConnection是java的标准类，什么都没封装，用起来太原始，不方便，比如重访问的自定义，以及一些高级功能等。
| URLConnection | HTTPClient | |
|---|---|---|
| Proxies and SOCKS | Full support in Netscape browser, appletviewer, and applications (SOCKS: Version 4 only); no additional limitations from security policies. | Full support (SOCKS: Version 4 and 5); limited in applets however by security policies; in Netscape can't pick up the settings from the browser. |
| Authorization | Full support for Basic Authorization in Netscape (can use info given by the user for normal accesses outside of the applet); no support in appletviewer or applications. | Full support everywhere; however cannot access previously given info from Netscape, thereby possibly requesting the user to enter info (s)he has already given for a previous access. Also, you can add/implement additional authentication mechanisms yourself. |
| Methods | Only has GET and POST. | Has HEAD, GET, POST, PUT, DELETE, TRACE and OPTIONS, plus any arbitrary method. |
| Headers | Currently you can only set any request headers if you are doing a POST under Netscape; for GETs and the JDK you can't set any headers. | Allows any arbitrary headers to be sent and received. |
| Automatic Redirection Handling | Yes. | Yes (as allowed by the HTTP/1.1 spec). |
| Persistent Connections | No support currently in JDK; under Netscape uses HTTP/1.0 Keep-Alive's. | Supports HTTP/1.0 Keep-Alive's and HTTP/1.1 persistence. |
| Pipelining of Requests | No. | Yes. |
| Can handle protocols other than HTTP | Theoretically; however only http is currently implemented. | No. |
| Can do HTTP over SSL (https) | Under Netscape, yes. Using Appletviewer or in an application, no. | No (not yet). |
| Source code available | No. | Yes. |
3.案例
URLConnection
String urlAddress = "http://192.168.1.102:8080/AndroidServer/login.do"; URL url; HttpURLConnection uRLConnection; public UrlConnectionToServer(){ } //向服务器发送get请求public String doGet(String username,String password){ String getUrl = urlAddress + "?username="+username+"&password="+password; try { url = new URL(getUrl); uRLConnection = (HttpURLConnection)url.openConnection(); InputStream is = uRLConnection.getInputStream(); BufferedReader br = new BufferedReader(new InputStreamReader(is)); String response = ""; String readLine = null; while((readLine =br.readLine()) != null){ //response = br.readLine(); response = response + readLine; } is.close(); br.close(); uRLConnection.disconnect(); return response; } catch (MalformedURLException e) { e.printStackTrace(); return null; } catch (IOException e) { e.printStackTrace(); return null; } } //向服务器发送post请求public String doPost(String username,String password){ try { url = new URL(urlAddress); uRLConnection = (HttpURLConnection)url.openConnection(); uRLConnection.setDoInput(true); uRLConnection.setDoOutput(true); uRLConnection.setRequestMethod("POST"); uRLConnection.setUseCaches(false); uRLConnection.setInstanceFollowRedirects(false); uRLConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); uRLConnection.connect(); DataOutputStream out = new DataOutputStream(uRLConnection.getOutputStream()); String content = "username="+username+"&password="+password; out.writeBytes(content); out.flush(); out.close(); InputStream is = uRLConnection.getInputStream(); BufferedReader br = new BufferedReader(new InputStreamReader(is)); String response = ""; String readLine = null; while((readLine =br.readLine()) != null){ //response = br.readLine(); response = response + readLine; } is.close(); br.close(); uRLConnection.disconnect(); return response; } catch (MalformedURLException e) { e.printStackTrace(); return null; } catch (IOException e) { e.printStackTrace(); return null; } } HTTPClient
String urlAddress = "http://192.168.1.102:8080/qualityserver/login.do";
public HttpClientServer(){ } public String doGet(String username,String password){ String getUrl = urlAddress + "?username="+username+"&password="+password; HttpGet httpGet = new HttpGet(getUrl); HttpParams hp = httpGet.getParams(); hp.getParameter("true"); //hp. //httpGet.setp HttpClient hc = new DefaultHttpClient(); try { HttpResponse ht = hc.execute(httpGet); if(ht.getStatusLine().getStatusCode() == HttpStatus.SC_OK){ HttpEntity he = ht.getEntity(); InputStream is = he.getContent(); BufferedReader br = new BufferedReader(new InputStreamReader(is)); String response = ""; String readLine = null; while((readLine =br.readLine()) != null){ //response = br.readLine(); response = response + readLine; } is.close(); br.close(); //String str = EntityUtils.toString(he); System.out.println("========="+response); return response; }else{ return "error"; } } catch (ClientProtocolException e) { // TODO Auto-generated catch block e.printStackTrace(); return "exception"; } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); return "exception"; }
} public String doPost(String username,String password){ //String getUrl = urlAddress + "?username="+username+"&password="+password; HttpPost httpPost = new HttpPost(urlAddress); List params = new ArrayList(); NameValuePair pair1 = new BasicNameValuePair("username", username); NameValuePair pair2 = new BasicNameValuePair("password", password); params.add(pair1); params.add(pair2); HttpEntity he; try { he = new UrlEncodedFormEntity(params, "gbk"); httpPost.setEntity(he); } catch (UnsupportedEncodingException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } HttpClient hc = new DefaultHttpClient(); try { HttpResponse ht = hc.execute(httpPost); //连接成功 if(ht.getStatusLine().getStatusCode() == HttpStatus.SC_OK){ HttpEntity het = ht.getEntity(); InputStream is = het.getContent(); BufferedReader br = new BufferedReader(new InputStreamReader(is)); String response = ""; String readLine = null; while((readLine =br.readLine()) != null){ //response = br.readLine(); response = response + readLine; } is.close(); br.close(); //String str = EntityUtils.toString(he); System.out.println("=========&&"+response); return response; }else{ return "error"; } } catch (ClientProtocolException e) { // TODO Auto-generated catch block e.printStackTrace(); return "exception"; } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); return "exception"; }
} servlet端json转化：
resp.setContentType("text/json"); resp.setCharacterEncoding("UTF-8"); toDo = new ToDo(); List<UserBean> list = new ArrayList<UserBean>(); list = toDo.queryUsers(mySession); String body; //设定JSON JSONArray array = new JSONArray(); for(UserBean bean : list) { JSONObject obj = new JSONObject(); try { obj.put("username", bean.getUserName()); obj.put("password", bean.getPassWord()); }catch(Exception e){} array.add(obj); } pw.write(array.toString()); System.out.println(array.toString()); Android端接收：
String urlAddress = "http://192.168.1.102:8080/qualityserver/result.do"; String body = getContent(urlAddress); JSONArray array = new JSONArray(body); for(int i=0;i<array.length();i++) { obj = array.getJSONObject(i); sb.append("用户名:").append(obj.getString("username")).append("\t"); sb.append("密码:").append(obj.getString("password")).append("\n"); HashMap<String, Object> map = new HashMap<String, Object>(); try { userName = obj.getString("username"); passWord = obj.getString("password"); } catch (JSONException e) { e.printStackTrace(); } map.put("username", userName); map.put("password", passWord); listItem.add(map); } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } if(sb!=null) { showResult.setText("用户名和密码信息："); showResult.setTextSize(20); } else extracted(); //设置adapter SimpleAdapter simple = new SimpleAdapter(this,listItem, android.R.layout.simple_list_item_2, new String[]{"username","password"}, new int[]{android.R.id.text1,android.R.id.text2}); listResult.setAdapter(simple); listResult.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { int positionId = (int) (id+1); Toast.makeText(MainActivity.this, "ID："+positionId, Toast.LENGTH_LONG).show(); } }); } private void extracted() { showResult.setText("没有有效的数据！"); } //和服务器连接 private String getContent(String url)throws Exception{ StringBuilder sb = new StringBuilder(); HttpClient client =new DefaultHttpClient(); HttpParams httpParams =client.getParams(); HttpConnectionParams.setConnectionTimeout(httpParams, 3000); HttpConnectionParams.setSoTimeout(httpParams, 5000); HttpResponse response = client.execute(new HttpGet(url)); HttpEntity entity =response.getEntity(); if(entity !=null){ BufferedReader reader = new BufferedReader(new InputStreamReader (entity.getContent(),"UTF-8"),8192); String line =null; while ((line= reader.readLine())!=null){ sb.append(line +"\n"); } reader.close(); } return sb.toString(); } 这篇关于Android网络HttpURLConnection和HttpClient的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！
