php - How to store data on data base in android studio with API 23? -

most of times don't post because can find need in others posts, 1 has me few days now, how guys store in databases? here java code

@override protected object doinbackground(object[] params) {    try {             url url = null;             url = new url("http://www.myserver.com/register.php");             httpurlconnection conn = null;             conn = (httpurlconnection) url.openconnection();             conn.setreadtimeout(connection_timeout);             conn.setconnecttimeout(connection_timeout);             conn.setrequestmethod("post");             conn.setdoinput(true);             conn.setdooutput(true);              dataoutputstream os = new dataoutputstream(conn.getoutputstream());              uri.builder builder = new uri.builder().appendqueryparameter("name", user.name)                                                     .appendqueryparameter("age", user.age + "")                                                     .appendqueryparameter("username", user.username)                                                     .appendqueryparameter("password", user.password);              string query = builder.build().getencodedquery();              bufferedwriter writer = new bufferedwriter(new outputstreamwriter(os, "utf-8"));              writer.write(query);             writer.flush();             writer.close();             os.close();          } catch (malformedurlexception e) {             e.printstacktrace();         } catch (protocolexception e) {             e.printstacktrace();         } catch (ioexception e) {             e.printstacktrace();         }   return null;   } 

i tried lot of solutions nothing works, can't put in database. every time find help, outdated. here php file. thank you.

<?php   $con = mysql_connect("hostname", "user", "passwd") or die (mysql_error()); mysql_select_db("database", $con) or die (mysql_error());  echo $name = $_post["name"]; echo $age = $_post["age"]; echo $username = $_post["username"]; echo $password = $_post["password"];   $sql_query = "insert userinfo values('', '$name','$age','$username','$password');";  $req = mysql_query($sql_query); ?> 

i used mysqli didn't work tried mysql_ here was

$statement = mysqli_prepare($con, "insert userinfo (name, age, username, password) value (?, ?, ?, ?);"); mysqli_stmt_bind_param($statement, "siss", $name, $age, $username, $password); mysqli_stmt_execute($statement);  mysqli_stmt_close($statement); mysqli_close($con); 

i haven't "exeption" or "failed to" , don't inderstand are

       e/surface﹕ getslotfrombufferlocked: unknown buffer: 0xab759330 

there android manifest

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android"     package="app_invaders.depaname" >  <uses-permission android:name="android.permission.internet"/>  <application     android:allowbackup="true"     android:icon="@mipmap/ic_launcher"     android:label="@string/app_name"     android:theme="@style/apptheme" >     <activity         android:name=".mainactivity"         android:label="@string/app_name" >         <intent-filter>             <action android:name="android.intent.action.main" />              <category android:name="android.intent.category.launcher" />         </intent-filter>     </activity>     <activity         android:name=".login"         android:label="@string/title_activity_login" >     </activity>     <activity         android:name=".register"         android:label="@string/title_activity_register" >     </activity> </application>  </manifest> 

i guess, you're trying add id value in,

$sql_query = "insert userinfo values('', '$name','$age','$username','$password');"; 

instead of this. try using this,

$sql_query = "insert userinfo values('$name','$age','$username','$password')";