android 请求网络 和 httpclient的使用上传下载

访问网络最主要的也就是 http协议了。

http协议很简单，但是很重要。

直接上代码了，里面都是1个代码块 代码块的，用哪一部分直接拷出去用就好了。

1.访问网络用 get 和 post  自己组拼提交参数 ，httpclient 方式提交

2.上传 和 下载 

3.比如访问服务器后 返回来的 xml 和 json 的简单解析方法

String  path = "http://192.168.13.1";String  username ="ll";String  pwd="123";/**   get 组拼    */public void  httpGet()throws Exception {String param1 = URLEncoder.encode(username);String param2 = URLEncoder.encode(pwd);URL url = new URL(path + "?name=" + param1 + "&password=" + param2);HttpURLConnection conn = (HttpURLConnection) url.openConnection();conn.setRequestMethod("GET");conn.setReadTimeout(5000);// 数据并没有发送给服务器// 获取服务器返回的流信息InputStream in = conn.getInputStream();byte[] result = StreamTool.getBytes(in);//return new String(result);}/** post  组拼   */public  void  httpPost() throws Exception {URL url = new URL(path);String param1 = URLEncoder.encode(username);String param2 = URLEncoder.encode(pwd);//开始连接HttpURLConnection conn = (HttpURLConnection) url.openConnection();String data = "username=" + param1 + "&password=" + param2;//设置方式 postconn.setRequestMethod("POST");//timeout  5000conn.setConnectTimeout(5000);// 设置 http协议可以向服务器写数据conn.setDoOutput(true);// 设置http协议的消息头conn.setRequestProperty("Content-Type","application/x-www-form-urlencoded");conn.setRequestProperty("Content-Length",  String.valueOf(data.length()));// 把我们准备好的data数据写给服务器OutputStream os = conn.getOutputStream();os.write(data.getBytes());// httpurlconnection 底层实现 outputstream 是一个缓冲输出流// 只要我们获取任何一个服务器返回的信息 , 数据就会被提交给服务器 , 得到服务器返回的流信息int code = conn.getResponseCode();if (code == 200) {InputStream is = conn.getInputStream();byte[] result = StreamTool.getBytes(is);String ss= new String(result);}}/**   httpclient  get   */public void httpClentGet () throws Exception{//获取到一个浏览器的实例 HttpClient client = new DefaultHttpClient();//准备请求的地址 String param1 = URLEncoder.encode(username);String param2 = URLEncoder.encode(pwd);HttpGet httpGet = new HttpGet(path + "?name=" + param1 + "&password=" + param2);//敲回车 发请求 HttpResponse  ressponse = client.execute(httpGet);int code = ressponse.getStatusLine().getStatusCode();if( code ==  200){InputStream is  =ressponse.getEntity().getContent();//byte[] result = StreamTool.getBytes(is);}}//不需要的时候关闭 httpclient   client.getConnectionManager().shutdown();/**    httpclient  post **/public  void httpClentPost() throws Exception{//1. 获取到一个浏览器的实例 HttpClient client = new DefaultHttpClient();HttpPost httppost = new HttpPost(path);// 键值对  BasicNameValuePairList<NameValuePair> parameters = new ArrayList<NameValuePair>();parameters.add(new BasicNameValuePair("username", username));parameters.add(new BasicNameValuePair("pwd", pwd));UrlEncodedFormEntity entity = new UrlEncodedFormEntity(parameters, "utf-8");//3.设置post请求的数据实体 httppost.setEntity(entity);//4. 发送数据给服务器HttpResponse  ressponse = client.execute(httppost);int code = ressponse.getStatusLine().getStatusCode();if(code == 200){InputStream is  =ressponse.getEntity().getContent();byte[] result = StreamTool.getBytes(is);//return new String(result);}}/*** 下载一个东西    ***/public void getFileData(Context context){try {     HttpClient client = new DefaultHttpClient();     HttpGet httpGet = new HttpGet(path); //执行 HttpResponse  ressponse = client.execute(httpGet); int code = ressponse.getStatusLine().getStatusCode();       if(code == HttpStatus.SC_OK){InputStream in =ressponse.getEntity().getContent();//图片 //Bitmap bitmap = BitmapFactory.decodeStream(in);//in.close();//文件什么的比如读取了是要写在本地的//小文件直接读取   大文件读取一点写一点//byte[] result = StreamTool.getBytes(in);// //这里可以得到文件的类型 如image/jpg /zip /tiff 等等 但是发现并不是十分有效，有时明明后缀是.rar但是取到的是null，这点特别说明                        System.out.println(ressponse.getEntity().getContentType());                        //可以判断是否是文件数据流                        System.out.println(ressponse.getEntity().isStreaming());                        //设置本地保存的文件                        //File storeFile = new File("c:/0431la.zip");                          String path="sdcard/aa.txt";                        FileOutputStream output = context.openFileOutput(path, context.MODE_PRIVATE);                        //得到网络资源并写入文件                        InputStream input = ressponse.getEntity().getContent();                        byte b[] = new byte[1024];                        int j = 0;                        while( (j = input.read(b))!=-1){                             output.write(b,0,j);                        }                        output.flush();                        output.close();      }} catch (Exception e) {// TODO: handle exception}}/** * 提交数据给服务器 带一个文件  * @param filepath 文件在手机上的路径  */public void PostData(String filepath) throws Exception{// 实例化上传数据的 数组  part [] username  pwdPart[] parts = {  new StringPart("username", username),   new StringPart("pwd", pwd),   new FilePart("file", new File(filepath))  };PostMethod file_Post = new PostMethod(path);    //                              多种类型的数据实体file_Post.setRequestEntity(new MultipartRequestEntity(parts, file_Post.getParams()));//创建 clientorg.apache.commons.httpclient.HttpClient client = new org.apache.commons.httpclient.HttpClient();        //timeoutclient.getHttpConnectionManager().getParams().setConnectionTimeout(5000);//执行int status = client.executeMethod(file_Post);if(status==200){}}//传送文件public void setFile() throws Exception{ HttpClient httpclient = new DefaultHttpClient();        HttpPost httppost = new HttpPost("http://192.168.1.1");        File file = new File(path);        InputStreamEntity reqEntity = new InputStreamEntity(                new FileInputStream(file), -1);        reqEntity.setContentType("binary/octet-stream");        reqEntity.setChunked(true);         // FileEntity entity = new FileEntity(file, "binary/octet-stream");        httppost.setEntity(reqEntity);        System.out.println("executing request " + httppost.getRequestLine());        HttpResponse response = httpclient.execute(httppost);          if(response.getStatusLine().getStatusCode() == 200){                           }}/** 1. *  一般访问了就会返回来1个  webservice *  pull解析访问webservice 返回来的xml *   **/public void  pullJX(byte[]  bb)  throws Exception{// byte[] bb = EntityUtils.toByteArray(response.getEntity()); XmlPullParser pullParser = Xml.newPullParser(); pullParser.setInput(new ByteArrayInputStream(bb), "UTF-8"); int event = pullParser.getEventType();        List<Object> info; while(event != XmlPullParser.END_DOCUMENT){      switch (event) {   case XmlPullParser.START_DOCUMENT:info = new ArrayList<Object>();break;   case XmlPullParser.START_TAG:if("aa".equals(pullParser.getName())){String id = pullParser.nextText().toString();}break;   case XmlPullParser.END_TAG:  if("aa".equals(pullParser.getName())){  }      break;      }event = pullParser.next();  }}/**2. *  解析 json  数据 [{id:"001",name:"lilei",age:"20"},{id:"002",name:"zhangjia",age:"30"}] */private static List parseJSON(InputStream  in) throws Exception{byte[] data = StreamTool.getBytes(in);String s =new String(data);// 转换成  json 数组对象   [{"001","ll","20"},{"002","zj","30"},]JSONArray json = new JSONArray(s);for (int i = 0; i < json.length() ; i++) {  JSONObject j = json.getJSONObject(i);      String aa1 = j.getString("id");      String aa2 = j.getString("name");      String aa3 = j.getString("age");}  return  null;   }

HttpClient其实是一个interface类型，HttpClient封装了对象需要执行的Http请求、身份验证、连接管理和其它特性

HttpClient有三个已知的实现类分别是：

AbstractHttpClient, AndroidHttpClient, DefaultHttpClient

 AndroidHttpClient是对HttpClient的包装，内部带访问连接器，并设置为可以多线程使用，

public class MyApplication extends Application{ private AndroidHttpClient httpClient;         //  application oncreate的时候创建      public void onCreate(){          super.onCreate();          httpClient =  AndroidHttpClient.newInstance("Android");      }           //供外部调用      public AndroidHttpClient getHttpClient() {        if (httpClient == null){       httpClient = AndroidHttpClient.newInstance("Android");        }        return httpClient;      }  @Override  public void onLowMemory() {    super.onLowMemory();    shutdownHttpClient();  }  @Override  public void onTerminate() {    super.onTerminate();    shutdownHttpClient();  }        //关闭  private void shutdownHttpClient() {    if (httpClient != null) {      if (httpClient.getConnectionManager() != null) {        httpClient.getConnectionManager().shutdown();      }      httpClient.close();      httpClient = null;    }  }  }

外部调用的话

AndroidHttpClient httpClient = ((MyApplication)getApplication()).getHttpClient();