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 arrayList = new ArrayList();
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 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() {
@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 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
