HttpUrlConnection的使用

1.发送get请求：

connect可以不写，url.openconnection已经包含了connect功能

public void doGet() {    try {        URL url = new URL("http://www.baidu.com");        HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();        httpURLConnection.connect();        InputStream inputStream = httpURLConnection.getInputStream();//字节输入流        InputStreamReader reader = new InputStreamReader(inputStream);//字符输入流        BufferedReader bufferedReader = new BufferedReader(reader);//带缓冲区的字符输入流        String strLine = null;        String strResult = "";        int iCode = httpURLConnection.getResponseCode();//得到状态码，200表示成功        while ((strLine = bufferedReader.readLine()) != null) {            strResult += strLine + "\n";        }        Log.d("qf", strResult);        bufferedReader.close();//关闭流        httpURLConnection.disconnect();//关闭socket连接，如果还要使用这个连接，可以不关闭    } catch (Exception e) {        e.printStackTrace();    }}

2.发送post请求：

public void doPost() {    try {        URL url = new URL("http://zhushou.72g.com/app/game/game_list/");        try {            HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();            httpURLConnection.setRequestMethod("POST");            httpURLConnection.setDoOutput(true);            httpURLConnection.connect();            OutputStream os = httpURLConnection.getOutputStream();            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));            String content = "platform=2";            writer.write(content);            writer.flush();            writer.close();            BufferedReader br = new BufferedReader(new InputStreamReader(httpURLConnection.getInputStream(), "UTF-8"));            String line = null;            StringBuilder sb = new StringBuilder();            while ((line = br.readLine()) != null) {                sb.append(line);            }            br.close();            String result = sb.toString();            Log.d("qf", result);        } catch (IOException e) {            e.printStackTrace();        }    } catch (MalformedURLException e) {        e.printStackTrace();    }}

3.下载

// 用于异步的显示图片private Handler handler = new Handler() {    public void handleMessage(Message msg) {        switch (msg.what) {            //下载成功            case LOAD_SUCCESS:                // 获取图片的文件对象                File file = new File(Environment.getExternalStorageDirectory(), "pic.jpg");                FileInputStream fis = null;                try {                    fis = new FileInputStream(file);                    Bitmap bitmap = BitmapFactory.decodeStream(fis);                    image.setImageBitmap(bitmap);                } catch (FileNotFoundException e) {                    e.printStackTrace();                }                break;            //下载失败            case LOAD_ERROR:                Toast.makeText(MainActivity.this, "加载失败", Toast.LENGTH_SHORT).show();                break;        }    }    ;};//下载图片的主方法private void getPicture() {    URL url = null;    InputStream is = null;    FileOutputStream fos = null;    try {        //构建图片的url地址        url = new URL("http://avatar.csdn.net/C/6/8/1_bz419927089.jpg");        //开启连接        HttpURLConnection conn = (HttpURLConnection) url.openConnection();        //设置超时的时间，5000毫秒即5秒        conn.setConnectTimeout(5000);        //设置获取图片的方式为GET        //conn.setRequestMethod("GET");        //响应码为200，则访问成功        if (conn.getResponseCode() == 200) {            //获取连接的输入流，这个输入流就是图片的输入流            is = conn.getInputStream();            //构建一个file对象用于存储图片            File file = new File("/sdcard/pic.jpg");            fos = new FileOutputStream(file);            int len = 0;            byte[] buffer = new byte[1024];            //将输入流写入到我们定义好的文件中            while ((len = is.read(buffer)) != -1) {                fos.write(buffer, 0, len);            }            //将缓冲刷入文件            fos.flush();            //告诉handler，图片已经下载成功            handler.sendEmptyMessage(LOAD_SUCCESS);        }    } catch (Exception e) {        //告诉handler，图片已经下载失败        handler.sendEmptyMessage(LOAD_ERROR);        e.printStackTrace();    } finally {        //在最后，将各种流关闭        try {            if (is != null) {                is.close();            }            if (fos != null) {                fos.close();            }        } catch (Exception e) {            handler.sendEmptyMessage(LOAD_ERROR);            e.printStackTrace();        }    }}

4.上传：

public void upload(){    List<String> list  = new ArrayList<String>();      list.add("/sdcard/Download/aaa.jpg");    try {        String BOUNDARY = "---------7d4a6d158c9"; // 定义数据分隔线        URL url = new URL("http://10.2.152.133/upload.php");        HttpURLConnection conn = (HttpURLConnection) url.openConnection();        // 发送POST请求必须设置如下两行        conn.setDoOutput(true);        conn.setDoInput(true);        conn.setUseCaches(false);        conn.setRequestMethod("POST");        conn.setRequestProperty("connection", "Keep-Alive");        //conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");        //conn.setRequestProperty("Charsert", "UTF-8");        conn.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + BOUNDARY);        OutputStream out = new DataOutputStream(conn.getOutputStream());        byte[] end_data = ("\r\n--" + BOUNDARY + "--\r\n").getBytes();// 定义最后数据分隔线        int leng = list.size();        for(int i=0;i<leng;i++){            String fname = list.get(i);            File file = new File(fname);            StringBuilder sb = new StringBuilder();            sb.append("--");            sb.append(BOUNDARY);            sb.append("\r\n");            sb.append("Content-Disposition: form-data;name=\"upload_file"+i+"\";filename=\""+ file.getName() + "\"\r\n");            sb.append("Content-Type:application/octet-stream\r\n\r\n");            byte[] data = sb.toString().getBytes();            out.write(data);            DataInputStream in = new DataInputStream(new FileInputStream(file));            int bytes = 0;            byte[] bufferOut = new byte[1024];            while ((bytes = in.read(bufferOut)) != -1) {                out.write(bufferOut, 0, bytes);            }            out.write("\r\n".getBytes()); //多个文件时，二个文件之间加入这个            in.close();        }        out.write(end_data);        out.flush();        out.close();        // 定义BufferedReader输入流来读取URL的响应        BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));        String line = null;        while ((line = reader.readLine()) != null) {            System.out.println(line);        }    } catch (Exception e) {        System.out.println("发送POST请求出现异常！" + e);        e.printStackTrace();    }}