Android基础网络第二天

1 get方式提交数据乱码的解决

一般在公司开发客户端和服务端的编码要保持一致。
android端的默认编码是utf-8;
做url请求时需要对参数进行URLEncode编码.

final String urlStr = "http://192.168.1.104:8080/itheima74/servlet/LoginServlet?username=" + URLEncoder.encode(username, "utf-8") + "&pwd=" + URLEncoder.encode(password, "utf-8");

2 post方式提交数据乱码解决

connection.setDoOutput(true);
OutputStream out = connection.getOutputStream();
out.write(("username=" + URLEncoder.encode(username, "utf-8") + "&pwd=" + URLEncoder.encode(password, "utf-8")).getBytes());

2 服务器端都是这样

public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        
        String username = new String(request.getParameter("username").getBytes("iso-8859-1"),"utf-8");
        String pwd = new String(request.getParameter("pwd").getBytes("iso-8859-1"),"utf-8");

}

3 httpclient方式提交数据到服务器

 HttpClient:

get方式:
        //使用HttpClient请求服务器将用户密码发送服务器验证
            try{
            String path = "http://192.168.13.83:8080/itheima74/servlet/LoginServlet?username="+URLEncoder.encode(username,"utf-8")+"&pwd="+URLEncoder.encode(password,"utf-8");
            //1.创建一个httpClient对象
            HttpClient httpclient = new DefaultHttpClient();
            
            //2.设置请求的方式
            HttpGet httpget = new HttpGet(path);
            //3.执行一个http请求
            HttpResponse response = httpclient.execute(httpget);
            //4.获取请求的状态码，
            StatusLine statusLine = response.getStatusLine();
            int code = statusLine.getStatusCode();
            
            //5.判断状态码后获取内容
            if(code == 200){
                HttpEntity entity = response.getEntity();//获取实体内容，中封装的有http请求返回的流信息
                InputStream inputStream = entity.getContent();
                //将流信息转换成字符串
                String result = StreamUtils.streamToString(inputStream);
                
                Message msg = Message.obtain();
                msg.what = 1;
                msg.obj = result;
                handler.sendMessage(msg);
            }
            
            }catch (Exception e) {
                e.printStackTrace();
            }
post方式：


        //使用UrlConncetion请求服务器将用户密码发送服务器验证
            try{
                    String path = "http://192.168.13.83:8080/itheima74/servlet/LoginServlet";
                    //1.创建一个httpclient对象
                    HttpClient httpclient = new DefaultHttpClient();
                    //2.创建一个请求方式
                    HttpPost httppost = new HttpPost(path);
                    //创建集合封装数据
                    ArrayList<BasicNameValuePair> arrayList = new ArrayList<BasicNameValuePair>();
                    BasicNameValuePair nameValuePair = new BasicNameValuePair("username",username);
                    arrayList.add(nameValuePair);
                    BasicNameValuePair nameValuePair1 = new BasicNameValuePair("pwd",password);
                    arrayList.add(nameValuePair1);
                    
                    //创建一个Entity
                    UrlEncodedFormEntity entity = new UrlEncodedFormEntity(arrayList, "utf-8");
                    //设置请求时的内容
                    httppost.setEntity(entity);
                    
                    //3.执行一个请求,返回一个response对象
                    HttpResponse response = httpclient.execute(httppost);
                    //4.获取状态码
                    int code = response.getStatusLine().getStatusCode();
                    //5.判断并获取内容
                    if(code == 200){
                        HttpEntity entity1 = response.getEntity();//获取实体内容，中封装的有http请求返回的流信息
                        InputStream inputStream = entity1.getContent();
                        //将流信息转换成字符串
                        String result = StreamUtils.streamToString(inputStream);
                        Message msg = Message.obtain();
                        msg.what = 2;
                        msg.obj = result;
                        handler.sendMessage(msg);
                    }

            }catch (Exception e) {
                e.printStackTrace();
            }

4开源项目get post 方式提交 (asyncHttpClient)

    get方式：


                public static void requestNetForGetLogin(final Context context,final Handler handler ,final String username, final String password) {
            //使用HttpClient请求服务器将用户密码发送服务器验证
            try{
            String path = "http://192.168.13.83:8080/itheima74/servlet/LoginServlet?username="+URLEncoder.encode(username,"utf-8")+"&pwd="+URLEncoder.encode(password,"utf-8");
    
            //创建一个AsyncHttpClient对象
            AsyncHttpClient asyncHttpClient = new AsyncHttpClient();
            asyncHttpClient.get(path, new AsyncHttpResponseHandler() {
                
                @Override
                public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
                    //statusCode:状态码    headers：头信息  responseBody：返回的内容，返回的实体
                    //判断状态码
                    if(statusCode == 200){
                        //获取结果
                        try {
                            String result = new String(responseBody,"utf-8");
                            Toast.makeText(context, result, 0).show();
                        } catch (UnsupportedEncodingException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }
                }
                
                @Override
                public void onFailure(int statusCode, Header[] headers,
                        byte[] responseBody, Throwable error) {
                    
                    System.out.println("...............onFailure");
                    
                }
            });
            }catch (Exception e) {
                e.printStackTrace();
            }
}


    post方式：


                String path = "http://192.168.13.83:8080/itheima74/servlet/LoginServlet";

        AsyncHttpClient asyncHttpClient = new AsyncHttpClient();
        RequestParams params = new RequestParams();
        params.put("username", username);
        params.put("pwd", password);
        
        //url:   parmas：请求时携带的参数信息   responseHandler：是一个匿名内部类接受成功过失败
        asyncHttpClient.post(path, params, new AsyncHttpResponseHandler() {
            
            @Override
            public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
                //statusCode:状态码    headers：头信息  responseBody：返回的内容，返回的实体
                
                //判断状态码
                if(statusCode == 200){
                    //获取结果
                    try {
                        String result = new String(responseBody,"utf-8");
                        Toast.makeText(context, result, 0).show();
                    } catch (UnsupportedEncodingException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                
            }
            
            @Override
            public void onFailure(int statusCode, Header[] headers,
                    byte[] responseBody, Throwable error) {
                
            }
        });

5 文件上传的操作

//服务器端
public void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {

        boolean isMultipart = ServletFileUpload.isMultipartContent(request);
        if (isMultipart) {   
            String realpath = request.getSession().getServletContext().getRealPath("/files");
            System.out.println("realpath-"+realpath);
            File dir = new File(realpath);
            if (!dir.exists())
                dir.mkdirs(); 
            FileItemFactory factory = new DiskFileItemFactory();
            ServletFileUpload upload = new ServletFileUpload(factory); 
            upload.setHeaderEncoding("UTF-8");
            try {
                List<FileItem> items = upload.parseRequest(request);
                for (FileItem item : items) {
                    if (item.isFormField()) { 
                        String name1 = item.getFieldName();
                        String value = item.getString("UTF-8");
                        System.out.println(name1 + "=" + value);
                    } else {
                        item.write(new File(dir, System.currentTimeMillis()
                                + item.getName().substring(item.getName().lastIndexOf("."))));
                    }
                }
            } catch (Exception e) {
                e.printStackTrace();
            }finally{
            }
        }
    }

使用第三方 AsyncHttpClient 做文件上传。
        
public void fileupload(View v){
    try{
    EditText et_filepath = (EditText) findViewById(R.id.et_filepath);
    //获取输入的文件地址
    String filepath = et_filepath.getText().toString().trim();
    
    //使用开源Utils做上传操作
    AsyncHttpClient asyncHttpClient = new AsyncHttpClient();
    
    RequestParams params = new RequestParams();
    params.put("filename", new File(filepath));
    //url : 请求服务器的url
    asyncHttpClient.post("http://192.168.13.83:8080/itheima74/servlet/UploaderServlet", params, new AsyncHttpResponseHandler() {
        
        @Override
        public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
            if(statusCode == 200){
                Toast.makeText(MainActivity.this, "上传成功", 0).show();
            }
        }
        @Override
        public void onFailure(int statusCode, Header[] headers,
                byte[] responseBody, Throwable error) {
        }
    });
    
    }catch (Exception e) {
        e.printStackTrace();
    }
}

6 多线程加速下载的原理

    1.线程越多下载越快？？ 不是。 与 本地网络带宽， 服务器资源的带宽 有关
    2.迅雷：3-5个。

    多线程下载的步骤：

    1.要知道服务端资源的大小。
    
        通过URLConnection请求服务器url获取。
        UrlConnection.getContentLength();//资源的大小
        
    2.在本地创建一个与服务端资源同样大小的一个文件（占位）
            //file :  文件； mode:文件的模式，rwd：直接写到底层设备，硬盘
            RandomAccessFile randomfile =new RandomAccessFile(File file,String mode)
                
            randomfile.setLength(long size);//创建一个文件和服务器资源一样大小
            
    3.要分配每个线程下载文件的开始位置和结束位置。
            
    4.开启线程去执行下载
            通过UrlConnection下载部分资源。
            注意：
             1.需要Range头，key：Range   value：bytes:0-499 
                    urlconnection.setRequestPropety("Range","bytes:0-499")
             2.需要设置每个线程在本地文件的保存的开始位置
                    RandomAccessFile randomfile =new RandomAccessFile(File file,String mode)
                    randomfile.seek(int startPostion);//本次线程下载保存的开始位置。
                    
    5.要知道每个线程下载完毕。

7 javase 多线程下载

8 多线程断点续传实现

9 Android版本多线程下载

        安智： sdcard没有判断。uc

10 开源项目实现多线程下载 (xutils)

    public void download(View v){
    EditText et_url = (EditText) findViewById(R.id.et_url);
    String url = et_url.getText().toString().trim();
    //1.创建httpUtils对象
    HttpUtils httpUtils = new HttpUtils();
    //2.调用download方法  url:下载的地址  target：下载的目录   callback：回调 
    httpUtils.download(url, "/sdcard/feiqiu/feiq.exe", new RequestCallBack<File>() {
        @Override
        public void onLoading(long total, long current, boolean isUploading) {
            System.out.println("total:"+total+";current:"+current);
            super.onLoading(total, current, isUploading);
        }
        @Override
        public void onSuccess(ResponseInfo<File> responseInfo) {
            System.out.println(responseInfo.result);
        }
        @Override
        public void onFailure(HttpException error, String msg) {
            // TODO Auto-generated method stub
            
        }
    });
}

2天网络内容大复习