Android网络基础

1.HttpClient

Apache提供的高效的网络访问模块。

Android 2.2(API 8)及以前使用HttpClient比价好，bug少。

但是在最新的Android版本中移除了，如果你还想使用这个，在build.gradle里面添加：

android {
    useLibrary 'org.apache.http.legacy'
}

具体使用方法：

String urlAddress = "http://192.168.1.102:8080/qualityserver/login.do";  
// 发送GET请求
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");  
    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) {  
        e.printStackTrace();  
        return "exception";  
    } catch (IOException e) {  
        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) { 
        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) {
        e.printStackTrace();  
        return "exception";  
    } catch (IOException e) {
        e.printStackTrace();  
        return "exception";  
    }     
}

2.HttpURLConnection

HttpURLConnection是一种多用途、轻量极的HTTP客户端，使用它来进行HTTP操作可以适用于大多数的应用程序。

注意事项

1. HttpURLConnection在Android 2.2及以前有一些bug。
2. 参看笔记：Android 4.0 Ice Cream Sandwich GET请求变POST请求

具体使用方法：

String urlAddress = "http://192.168.1.102:8080/AndroidServer/login.do";  
URL url;  
HttpURLConnection uRLConnection;  

//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;  
    }  
}

参考资料

http://blog.csdn.net/guolin_blog/article/details/12452307