Android Network request

HTTP requests and Responses

HTTP request Packet Structure

Cases:

Post/meme.php/home/user/login http/1.1    114.215.86.90    cache-control:no-cache    Postman-token:bd243d6b-da03-902f-0a2c-8e9377f6f6ed    Content-type:application/x-www-form-  urlencoded    Tel=13637829200&password=123456

HTTP response Packet Structure

Cases:

http/1.1 13:20:55 GMT    server:apache/2.4.6 (CentOS) php/5.6.14 x
        c4>-powered-by:php/5.6.14    Content-length:78    Keep-alive:timeout=5, max=100     Connection:keep-Alive    Content-type:application/json; charset=utf-8    {" Status ": 202," info ":" \u6b64\u7528\u6237\u4e0d\u5b58\u5728\uff01 "," data ":null}

HTTP request mode

Commonly used are post and get

Get mode

Fill in the parameters in the URL:http://xxxx.xx.com/xx.php?params1=value1&params2=value2

Post mode

The parameters are encoded in the request body. The encoding is included x-www-form-urlencoded with the form-data .

x-www-form-urlencodedis encoded in this way: tel=13637829200&password=123456

form-datais encoded in this way:

----WEBKITFORMBOUNDARY7MA4YWXKTRZU0GW  Content-disposition:form-data; name= "Tel"  13637829200  ----WEBKITFORMBOUNDARY7MA4YWXKTRZU0GW  Content-disposition:form-data; name= "Password"  123456  ----WEBKITFORMBOUNDARY7MA4YWXKTRZU0GW

x-www-form-urlencodedCan only pass the key value pair, form-data may pass the binary system

HttpClient & HttpURLConnection

HttpClient has been abandoned.

The use of HttpURLConnection

 Public classNetUtils { Public Staticstring post (string URL, string content) {HttpURLConnection conn=NULL; Try {                //Create a URL objectURL Murl =Newurl (URL); //Call the OpenConnection () method of the URL to get the HttpURLConnection objectconn =(HttpURLConnection) murl.openconnection (); Conn.setrequestmethod ("POST");//set the request method to postConn.setreadtimeout (5000);//set read timeout to 5 secondsConn.setconnecttimeout (10000);//Set the connection network timeout to 10 secondsConn.setdooutput (true);//set this method to allow content to be output to the server//parameters for the POST requestString data =content; //get an output stream to write data to the server, by default, the system does not allow the output of content to the serverOutputStream out = Conn.getoutputstream ();//get an output stream to write data to the serverOut.write (Data.getbytes ());                Out.flush ();                Out.close (); intResponsecode = Conn.getresponsecode ();//Calling this method eliminates the need to use the Conn.connect () method                if(Responsecode = = 200) {InputStream is=Conn.getinputstream (); String Response=Getstringfrominputstream (IS); returnresponse; } Else {                    Throw NewNetworkerrorexception ("Response status is" +responsecode); }            } Catch(Exception e) {e.printstacktrace (); } finally {                if(Conn! =NULL) {conn.disconnect ();//Close Connection                }            }            return NULL; }         Public Staticstring get (string url) {HttpURLConnection conn=NULL; Try {                //building a URL object with a string URLURL Murl =Newurl (URL); Conn=(HttpURLConnection) murl.openconnection (); Conn.setrequestmethod ("GET"); Conn.setreadtimeout (5000); Conn.setconnecttimeout (10000); intResponsecode =Conn.getresponsecode (); if(Responsecode = = 200) {InputStream is=Conn.getinputstream (); String Response=Getstringfrominputstream (IS); returnresponse; } Else {                    Throw NewNetworkerrorexception ("Response status is" +responsecode); }            } Catch(Exception e) {e.printstacktrace (); } finally {                if(Conn! =NULL) {conn.disconnect (); }            }            return NULL; }        Private StaticString Getstringfrominputstream (InputStream is)throwsIOException {bytearrayoutputstream os=NewBytearrayoutputstream (); //The template code must be skilled            byte[] buffer =New byte[1024]; intLen =-1;  while(len = is.read (buffer))! =-1) {os.write (buffer,0, Len);            } is.close (); String State= Os.tostring ();//converts the data in a stream into a string, using the encoding utf-8 (the emulator default encoding)Os.close (); returnState ; }    }

To add Network permissions:<uses-permission android:name="android.permission.INTERNET"/>

Synchronous & Asynchronous

Async mode:

//in the main thread new handler, the main thread will be processed later.     PrivateHandler Handler =NewHandler (); PrivateTextView TextView; @Overrideprotected voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);        Setcontentview (R.layout.activity_main); TextView=(TextView) Findviewbyid (R.id.text); NewThread (NewRunnable () {@Override Public voidrun () {//getting data from the network                FinalString response = Netutils.get ("http://www.baidu.com"); //sending processing operations to handlerHandler.post (NewRunnable () {@Override Public voidrun () {//updating the UI on the UI threadTextview.settext (response);            }                });    }}). Start (); }

Reference: http://www.jianshu.com/p/3141d4e46240

Android Network request