Android and PHP connection to MySQL Database -

i have following code , struggling working . there 2 errors in java file , can not find fix.

here mysqldata.java file

package com.example.qosmetre2; import java.io.bufferedreader; import java.io.inputstream; import java.io.inputstreamreader; import java.util.arraylist;  import org.apache.http.httpentity; import org.apache.http.httpresponse; import org.apache.http.namevaluepair; import org.apache.http.client.httpclient; import org.apache.http.client.entity.urlencodedformentity; import org.apache.http.client.methods.httppost; import org.apache.http.impl.client.defaulthttpclient; import org.json.jsonarray; import org.json.jsonexception; import org.json.jsonobject;  import android.app.activity; import android.net.parseexception; import android.os.bundle; import android.util.log; import android.widget.toast; import java.util.arraylist;  import java.util.hashmap;  import java.util.list;   import org.apache.http.namevaluepair;  import org.json.jsonarray;  import org.json.jsonexception;  import org.json.jsonobject;   import android.app.listactivity;  import android.app.progressdialog;  import android.content.intent;  import android.os.asynctask;  import android.os.bundle;  import android.util.log;  import android.view.view;  import android.widget.adapterview;  import android.widget.adapterview.onitemclicklistener;  import android.widget.listadapter;  import android.widget.listview;  import android.widget.simpleadapter;  import android.widget.textview;  public class mysqldata extends listactivity { @override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);     string result = null;     inputstream = null;     stringbuilder sb=null;     string result=null;     //http post      try{         httpclient httpclient = new defaulthttpclient();         httppost httppost = new httppost("http://localhost/android_test/fetch_data2.php");         httppost.setentity(new urlencodedformentity(namevaluepairs));         httpresponse response = httpclient.execute(httppost);         httpentity entity = response.getentity();         = entity.getcontent();     }catch(exception e){         log.e("log_tag", "error in http connection"+e.tostring());     }      //convert response string      try{         bufferedreader reader = new bufferedreader(new inputstreamreader(is,"iso-8859-1"),8);         sb = new stringbuilder();         sb.append(reader.readline() + "\n");         string line="0";         while ((line = reader.readline()) != null) {             sb.append(line + "\n");         }          is.close();         result=sb.tostring();      }catch(exception e){          log.e("log_tag", "error converting result "+e.tostring());     }     //paring data      string nam;     int rec_pow;     int tow;     int stat;      try{     jsonarray jarray = new jsonarray(result);     jsonobject json_data=null;      for(int i=0;i<jarray.length();i++){             json_data = jarray.getjsonobject(i);             nam=json_data.getstring("name");             rec_pow=json_data.getint("recieved_power");             tow=json_data.getint("tower");             stat=json_data.getint("status");      }      }catch(jsonexception e1){         toast.maketext(getbasecontext(), "could not parse data", toast.length_long).show();     }catch (parseexception e1){         e1.printstacktrace();      }  }  } 

there error on following 2 lines:

string result=null; httppost.setentity(new urlencodedformentity(namevaluepairs)); 

the first error says duplicate local variable result, , second error says namevaluepairs cannot resolved variable.

i have php file put in wamp server , infro thats showing on local server in application. read somewhere might have port forward acces app on internet, don't know. app wont run until errors fixed.

here php file fetch_data2.php

  <?php mysql_connect("888888","8888888","*******"); mysql_select_db("*******"); $q=mysql_query("select * users");    while($row=mysql_fetch_assoc($q))  $output[]=$row;    print(json_encode($output));    mysql_close();  ?> 

in reviewing code, see variable result defined twice , don't see namevaluepairs defined anywhere. think compiler correct :})