安卓中的网络编程

一. 使用URL对象请求网络

1、HttpURLConnection对象： 
//GET ： http://192.168.12.37:8080/xxx?a=aaa&b=bbb 
//POST : http://192.168.12.37:8080/xxx 
URL url = new URL(path); 
HttpURLConnection conn = (HttpURLConnection) url.openConnection();

2、设置请求头信息：GET（GET、POST）

conn.setRequestMethod("GET");
conn.setConnectTimeout(5000);

3、接收服务器端返回的响应数据，响应码：200 ok，404没有找到资源 ，503服务器端内部错误

int code = conn.getResponseCode();
if(code == 200){
      InputStream is = conn.getInputStream();

} 
GET和POST请求的请求参数设置不同： 
GET请求参数直接用？拼接到地址后面 
http://192.168.12.37:8080/xxx?a=aaa&b=bbb

POST请求参数
// 设置请求消息头信息
conn.setRequestProperty("Content-type","application/x-www-form-urlencoded");
conn.setRequestProperty("Content-length", reqData.length()+ "");
// 设置成允许发送数据给服务端，并发送数据
conn.setDoOutput(true);
conn.getOutputStream().write(reqData.getBytes());

二. HttpClient对象

GET方式:

final String path = "http://192.168.12.37:8080/androidServer01_login/servlet/ClientController"+ "?qqAccount="+ URLEncoder.encode(qqAccount)+ "&pwd="+ URLEncoder.encode(pwd); new Thread() {
    public void run() {
        // 1.获取一个代表浏览器的对象
        HttpClient client = new DefaultHttpClient();
        // 2.封装网址和请求参数到GET请求对象中
        HttpGet httpGet = new HttpGet(path);
        // 3.发送请求并接收响应数据
        try {
            HttpResponse response = client.execute(httpGet);
            // 获取响应状态吗
            int code = response.getStatusLine().getStatusCode();
            if (code == 200) {
                InputStream is = response.getEntity().getContent();
                //调用工具类方法，将输入流转换成字符串
                String res = ReadStreamUtil.stream2String(is);
                Message msg = Message.obtain();
                msg.obj = res;
                handler.sendMessage(msg);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }; }.start();

POST方式

final String path = "http://192.168.12.37:8080/androidServer01_login/servlet/ClientController";
new Thread() {
    public void run() {
        HttpClient client = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(path);
        List<BasicNameValuePair> parameters = new ArrayList<BasicNameValuePair>();
        parameters.add(new BasicNameValuePair("qqAccount", qqAccount));
        parameters.add(new BasicNameValuePair("pwd", pwd));
        try {
            UrlEncodedFormEntity encodedFormEntity = new UrlEncodedFormEntity(
                    parameters, "utf-8");
            httpPost.setEntity(encodedFormEntity);
            HttpResponse response = client.execute(httpPost);
            int code = response.getStatusLine().getStatusCode();
            if (code == 200) {
                InputStream is = response.getEntity().getContent();
                String res = ReadStreamUtil.stream2String(is);
                Message msg = Message.obtain();
                msg.obj = res;
                handler.sendMessage(msg);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    };
}.start();

三. 使用AsyncHttpClient对象请求网络（先引入第三方开源项目）

GET方式

AsyncHttpClient asyncHttpClient = new AsyncHttpClient();
asyncHttpClient.get("http://192.168.1.1:8080/xxx?a=aa&b=bb", new AsyncHttpResponseHandler() {
    @Override
    public void onSuccess(int statusCode, Header[] headers,
            byte[] responseBody) {
        Toast.makeText(getApplicationContext(),
                new String(responseBody), 0).show();
    }

    @Override
    public void onFailure(int statusCode, Header[] headers,
            byte[] responseBody, Throwable error) {
        Toast.makeText(getApplicationContext(),
                new String(responseBody), 0).show();
    }
});

POST方式

AsyncHttpClient asyncHttpClient = new AsyncHttpClient();
RequestParams params = new RequestParams();
params.add("qqAccount", qqAccount);
params.add("pwd", pwd);
asyncHttpClient.post("http://192.168.1.1:8080/xxx", params, new AsyncHttpResponseHandler() {
    @Override
    public void onSuccess(int statusCode, Header[] headers,
            byte[] responseBody) {
        Toast.makeText(getApplicationContext(),
                new String(responseBody), 0).show();
    }

    @Override
    public void onFailure(int statusCode, Header[] headers,
            byte[] responseBody, Throwable error) {
        Toast.makeText(getApplicationContext(),
                new String(responseBody), 0).show();
    }
});

4.XUtils

5.volley

6.okhttp

ps:文件上传使用AsyncHttpClient

多线程断点下载使用XUtils