Android 網絡請求HttpURLConnection 和 HttpClient詳解

Android通常經過http協議向服務端接口發送請求,經常使用有POST和GET傳輸方式。這種請求一般藉助於HttpClient,HttpClient 是 Apache Jakarta Common 下的子項目,能夠用來提供高效的、最新的、功能豐富的支持 HTTP 協議的客戶端編程工具包。經過HttpClient能夠不借助瀏覽器,從而簡化了客戶端與服務器端之間的交互。
html

HttpPost httpPost=new HttpPost(reqUrl);
java

HttpResponse httpResponse=new DefaultHttpClient().execute(httpPost);
android

DefaultHttpClient是HttpClient接口的默認實現,new DefaultHttpClient().execute(httpPost);則是使用一個匿名內部類來處理請求。該匿名內部類繼承自DefaultHttpClient,而DefaultHttpClient實現了HttpClient接口,全部能夠重寫HttpClient接口下execute的方法來處理請求。
編程

Android Post請求的兩種方式瀏覽器

(1)、HttpPost緩存

 

 HttpPost httpRequest =new HttpPost(url);
    List <NameValuePair> params=new ArrayList<NameValuePair>();//Post方式用NameValuePair[]陣列儲存
    params.add(new BasicNameValuePair("name","name"));
    try{   
     //設置請求參數
     httpRequest.setEntity(new UrlEncodedFormEntity(params,HTTP.UTF_8));
     //建立HttpClient實例
     HttpClient client = new DefaultHttpClient();
     //請求超時
     client.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 20000);
     //讀取超時
     client.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 20000    );
     //取得HTTP response
     HttpResponse httpResponse = client.execute(httpRequest);
     //若狀態碼爲200 ok 
     if(httpResponse.getStatusLine().getStatusCode()==200){
      //取出迴應字串
      String strResult=EntityUtils.toString(httpResponse.getEntity());
     }else{;
     }
    }catch(ClientProtocolException e){
     Toast.makeText(getApplicationContext(), e.getMessage().toString(),Toast.LENGTH_SHORT).show();
     e.printStackTrace();
    } catch (UnsupportedEncodingException e) {
     Toast.makeText(getApplicationContext(), e.getMessage().toString(),Toast.LENGTH_SHORT).show();
     e.printStackTrace();
    } catch (IOException e) {
     Toast.makeText(getApplicationContext(), e.getMessage().toString(),Toast.LENGTH_SHORT).show();
     e.printStackTrace();
    }

(2)、HttpURLConnection 
try{
     //創建鏈接
     URL url=new URL(url);
     HttpURLConnection httpConn=(HttpURLConnection)url.openConnection();
     
     ////設置鏈接屬性
     httpConn.setDoOutput(true);//使用 URL 鏈接進行輸出
     httpConn.setDoInput(true);//使用 URL 鏈接進行輸入
     httpConn.setUseCaches(false);//忽略緩存
     httpConn.setRequestMethod("POST");//設置URL請求方法
     String requestString = "客服端要以以流方式發送到服務端的數據...";
     
     //設置請求屬性
    //得到數據字節數據,請求數據流的編碼,必須和下面服務器端處理請求流的編碼一致
          byte[] requestStringBytes = requestString.getBytes("utf-8");
          httpConn.setRequestProperty("Content-length", "" + requestStringBytes.length);
          httpConn.setRequestProperty("Content-Type", "application/octet-stream");
          httpConn.setRequestProperty("Connection", "Keep-Alive");// 維持長鏈接
          httpConn.setRequestProperty("Charset", "UTF-8");
          //
          String name=URLEncoder.encode("張三","utf-8");
          httpConn.setRequestProperty("name", name);
          
          //創建輸出流,並寫入數據
          OutputStream outputStream = httpConn.getOutputStream();
          outputStream.write(requestStringBytes);
          outputStream.close();
         //得到響應狀態
          int responseCode = httpConn.getResponseCode();
          if(HttpURLConnection.HTTP_OK == responseCode){//鏈接成功
           
           //當正確響應時處理數據
           StringBuffer sb = new StringBuffer();
              String readLine;
              BufferedReader responseReader;
             //處理響應流,必須與服務器響應流輸出的編碼一致
              responseReader = new BufferedReader(new InputStreamReader(httpConn.getInputStream(), ENCODING_UTF_8));
              while ((readLine = responseReader.readLine()) != null) {
               sb.append(readLine).append("\n");
              }
              responseReader.close();
          }
    }catch(Exception ex){
     ex.printStackTrace();
    }服務器

HttpClient和HttpURLConnection是訪問HTTP的兩種方式,
HttpURLConnection是一個抽象類,繼承自URLConnection抽象類,基於標準Java接口(java.net),能夠實現簡單的基於URL請求、響應功能;HttpClient基於Apache接口(org.appache.http),使用起來更方面更強大。通常來講,使用這種接口比較多。運用這兩種方式,android能夠訪問網頁、下載圖片或文件、上傳文件,甚至參數配置適當時,能夠抓取服務器的不少數據。如用android作多圖上傳到服務器。
網絡

首先咱們先解析目標url請求時的一些參數app


如提請求的url地址Request URL,提交的方式Request Method,服務器端的IP地址及端口Remote Address,請求頭Request Headers,請求負載(表單參數)Request Payload,進而咱們就能夠在代碼裏面進行設置,而後發送請求ide

 

	/**
	 * 解析multipart/form-data方式提交的請求,並以一樣的方式再提交
	 */
	@SuppressWarnings("unchecked")
	public static HttpURLConnection doPostMultipartFormData(java.net.URL url,MultipartHttpServletRequest request){
		
		//分割字符串
		String BOUNDARY = UUIDTool.getUUID().toUpperCase();
		String BOUNDARYSP = "--";
		String BOUNDARYSTR = BOUNDARYSP + BOUNDARY;
		
		String LINESP = "\r\n";
		
		
		HttpURLConnection conn  = null;
		try{
		conn = (HttpURLConnection) url.openConnection();
		conn.setUseCaches(false);
		conn.setDoOutput(true);// 是否輸入參數
		conn.setConnectTimeout(3000);
		conn.setRequestMethod("POST");
		conn.setRequestProperty(
						"Accept",
						"text/html, application/xhtml+xml, */*");
		conn.setRequestProperty("Accept-Language", "zh-CN");
		conn.setRequestProperty(
						"User-Agent",
						"Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");
		conn.setRequestProperty("Connection", "Keep-Alive");
		conn.setRequestProperty("Accept-Charset", "UTF-8");
		//conn.setRequestProperty("contentType", "UTF-8");
		
		conn.setRequestProperty("Content-Type","multipart/form-data; boundary=" + BOUNDARY+"; charset=UTF-8");
		
		OutputStream out = new DataOutputStream(conn.getOutputStream()); 
		
		//byte[] end_data = ("\r\n--" + BOUNDARY + "--\r\n").getBytes();// 定義最後數據分隔線  
		
		StringBuffer multiParamsData = new StringBuffer();
		
		//組裝普通參數
		Map params = request.getParameterMap();
		for(Object key : params.keySet()){
			Object paramvalue = params.get(key);
			if(paramvalue!=null){
				if(paramvalue instanceof String[]){
					for(String param : (String[])paramvalue){
						multiParamsData.append(BOUNDARYSTR);
						multiParamsData.append(LINESP);
						multiParamsData.append("Content-Disposition: form-data; name=\""+key+"\"");
						multiParamsData.append(LINESP);
						multiParamsData.append("Content-Type: text/plain; charset=UTF-8");
						multiParamsData.append(LINESP);
						multiParamsData.append(LINESP);
						multiParamsData.append(param);
						multiParamsData.append(LINESP);
					}
				}else{
					multiParamsData.append(BOUNDARYSTR);
					multiParamsData.append(LINESP);
					multiParamsData.append("Content-Disposition: form-data; name=\""+key+"\"");
					multiParamsData.append(LINESP);
					multiParamsData.append("Content-Type: text/plain; charset=UTF-8");
					multiParamsData.append(LINESP);
					multiParamsData.append(LINESP);
					multiParamsData.append(paramvalue);
					multiParamsData.append(LINESP);
				}
			}
		}
		//System.out.println(multiParamsData.toString());
		out.write(multiParamsData.toString().getBytes("UTF-8"));
		//組裝文件
		Map<String, MultipartFile> files = request.getFileMap();
		int i = 1;
		for(String key : files.keySet()){
			StringBuffer multiFilesData = new StringBuffer();
			MultipartFile multipartFile = files.get(key);
			multiFilesData.append(BOUNDARYSTR);
			multiFilesData.append(LINESP);
			multiFilesData.append("Content-Disposition: form-data; name=\""+key+"\"; filename=\""+multipartFile.getOriginalFilename()+"\"");
			multiFilesData.append(LINESP);
			multiFilesData.append("Content-Type:application/octet-stream");
			multiFilesData.append(LINESP);
			multiFilesData.append(LINESP);
			//multiData.append(paramvalue);
			out.write(multiFilesData.toString().getBytes("UTF-8"));
			DataInputStream in = new DataInputStream(multipartFile.getInputStream());  
			int bytes = 0;  
            byte[] bufferOut = new byte[1024];  
            while ((bytes = in.read(bufferOut)) != -1) {  
                out.write(bufferOut, 0, bytes);  
            }  
        	out.write(LINESP.getBytes("UTF-8"));
            in.close();
           // System.out.println(multiFilesData.toString()+"<file content; length:"+readStream(multipartFile.getInputStream()).length+">");
		}
		 //System.out.println(BOUNDARYSTR+BOUNDARYSP);
		 out.write((BOUNDARYSTR+BOUNDARYSP+LINESP).getBytes("UTF-8"));  
         out.flush();    
         out.close(); 	
		//byte[] bypes = params.getBytes("UTF-8");
		//System.out.println("2>>>>>>"+new String(params,"UTF-8"));
//		conn.getOutputStream().write(params);
		}
		catch(ConnectException e){
		}
		catch(Exception e){
			logger.error("HttpRequest Error:",e);
		}
		return conn;
	}

 

HttpPsot結合Handle

 

new Thread(new Runnable() {
			
			@Override
			public void run() {
				// TODO Auto-generated method stub
				Message message=new Message();
				
				HttpPost httpPost=new HttpPost(reqUrl);
				try{
					httpPost.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
					HttpResponse httpResponse;
					try{
						httpResponse=new DefaultHttpClient().execute(httpPost);
						if(httpResponse.getStatusLine().getStatusCode()==200){
							String result = EntityUtils.toString(httpResponse.getEntity());
							if(!result.isEmpty()){
								message.what=0;
								message.obj=result;
								myHandler.sendMessage(message);
							}else{
								message.what=1;
								myHandler.sendMessage(message);
							}
						}else{
							message.what=1;
							myHandler.sendMessage(message);
						}
					}catch(Exception e){
						e.printStackTrace();
					}
				}catch(Exception e){
					e.printStackTrace();
				}
			}
		}).start();
static Handler myHandler=new Handler(){
		@Override
		public void handleMessage(android.os.Message msg) {
			
			if(msg.what==1){
				resultCallback.getReslt("1");
			}else if(msg.what==0){
				String result=(String) msg.obj;
			}
		};
	};

涉及到網絡數據傳輸,AndroidManifest.xml中要設置相應的權限。

 

 

<uses-permission android:name="android.permission.INTERNET" />

同時能夠對網絡狀態作一些相應的處理。

 

 

/** 
     * 檢測網絡是否鏈接
     * @return 
     */  
    private boolean isNetConnected() {  
        ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);  
        if (cm != null) {  
            NetworkInfo[] infos = cm.getAllNetworkInfo();  
            if (infos != null) {  
                for (NetworkInfo ni : infos) {  
                    if (ni.isConnected()) {  
                        return true;  
                    }  
                }  
            }  
        }  
        return false;  
    }  
	/**
	 * 設置網絡
	 * @param context
	 */
	private void isNetworkAvailable(Context context) {
		new AlertDialog.Builder(LoginActivity.this)
			.setTitle("網絡設置提示")
			.setMessage("網絡不可用,是否如今設置網絡?")
			.setPositiveButton("設置",
			 new DialogInterface.OnClickListener() {
				@Override
				public void onClick(DialogInterface dialog,
						int which) {
					if(android.os.Build.VERSION.SDK_INT > 10 ){
					     //3.0以上打開設置界面,也能夠直接用ACTION_WIRELESS_SETTINGS打開到wifi界面
					    startActivity(new Intent(android.provider.Settings.ACTION_SETTINGS));
					} else {
					    startActivity(new Intent(android.provider.Settings.ACTION_WIRELESS_SETTINGS));
					}
					overridePendingTransition(R.anim.push_left_in, R.anim.push_left_out);
				}
			 }).setNegativeButton("取消", null).show();
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