Java.lang.nullpointerException(Android)

Question

I was passing the value from AsyncTask class to the addValue method and get the value from getValue method. Here addValue works well but the getValue somehow cannot get the value and return Java.lang.nullPointerException in my apps when i click the image

package com.example.mobile_e_commerce;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.ResourceBundle;

import org.ksoap2.SoapEnvelope;
import org.ksoap2.serialization.PropertyInfo;
import org.ksoap2.serialization.SoapObject;
import org.ksoap2.serialization.SoapSerializationEnvelope;
import org.ksoap2.transport.HttpTransportSE;

import com.example.mobile_e_commerce.dummy.ProductInfo.ProductItem;

import android.app.Activity;
import android.app.Fragment;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.GridView;
import android.widget.Toast;
//include soap passing here

public class ProductCollection extends Activity {

public final static String EXTRA_MESSAGE = "com.example.mobile_e_commerce.product_name";
private static final ResourceBundle rb = ResourceBundle.getBundle("com.example.mobile_e_commerce.webserviceurl");
public static Map<String, ProductItem> ITEM_MAP = new HashMap<String, ProductItem>();


//Class involve asynctask(background running)//
public class objectTransfer extends AsyncTask<Void,Void,Void>{

the web services url and soap action all listed down here but i tested already and return value back too.

    private final String NAMESPACE = rb.getString("WSDLTargetNamespace");
    private  final String SoapURL = rb.getString("SoapAddress");
    private final String SOAP_ACTION = rb.getString("SoapAction");
    private final String METHOD_NAME = rb.getString("OperationName");
    private final String SOAP_ACTION2 = rb.getString("SoapAction2");
    private final String METHOD_NAME2 = rb.getString("OperationName2");
    private final String SOAP_ACTION3 = rb.getString("SoapAction3");
    private final String METHOD_NAME3 = rb.getString("OperationName3");
    private final String SOAP_ACTION4 = rb.getString("SoapAction4");
    private final String METHOD_NAME4 = rb.getString("OperationName4");
    private final String SOAP_ACTION5 = rb.getString("SoapAction5");
    private final String METHOD_NAME5 = rb.getString("OperationName5");
    private final String SOAP_ACTION6 = rb.getString("SoapAction6");//image location
    private final String METHOD_NAME6 = rb.getString("OperationName6");//image location
    private final String SOAP_ACTION7 = rb.getString("SoapAction7");
    private final String METHOD_NAME7 = rb.getString("OperationName7");

    //private Activity activity = new Activity();
  //  ImageView imageView = (ImageView)getActivity().findViewById(R.id.productImgDisplay);


    /**
     * A map of sample (dummy) items, by ID.
     */


    //  private File file = new File(Integer.toString(R.drawable.search));

         private String[] valuePass = new String[100];

         private int i;
         PropertyInfo pi = new PropertyInfo();


         private int n =0;
         PropertyInfo getInfo = new PropertyInfo();
         //  private int number = 0;



     @Override
      protected Void doInBackground(Void... arg0) {
         try
            {
            //get the no of the product
                Object response2 = null;
                    SoapObject request2 = new SoapObject(NAMESPACE,METHOD_NAME5);
                    SoapSerializationEnvelope envelope2 = new SoapSerializationEnvelope(SoapEnvelope.VER11);

                    envelope2.dotNet = true;

                envelope2.setOutputSoapObject(request2);

                HttpTransportSE httpTransport2 = new HttpTransportSE(SoapURL);

                httpTransport2.call(SOAP_ACTION5, envelope2);
                response2 = envelope2.getResponse();
                i = Integer.parseInt(response2.toString());

                    try
                    {
                        //get the name of the product
                        Object response = null;

                        while(n < i)
                        {
                            SoapObject request = new SoapObject(NAMESPACE,METHOD_NAME);
                            SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);

                                    envelope.dotNet = true;
                                    request.addProperty("number", n);


                        envelope.setOutputSoapObject(request);

                        HttpTransportSE httpTransport = new HttpTransportSE(SoapURL);

                    httpTransport.call(SOAP_ACTION, envelope);
                    response = envelope.getResponse();

                    //imageurl equal to byte type image data,will add to WS later



                         valuePass[n] = response.toString();
                        // Log.e("Value", valuePass[n]);
                         n++;

                         addValue(new ProductItem(Integer.toString(n) ,valuePass[n]));

                        }
                    }
                    catch (Exception exception)
                    {
                        exception.printStackTrace();
                        Log.e("Apps Error", exception.toString());
                    }
            }
            catch (Exception exception)
            {
                exception.printStackTrace();
                Log.e("Apps Error", exception.toString());
            }
                    return null;

     }

}

the addValue method should work well can include in the onBackground method above.I will try to check here later.

public void addValue(ProductItem Item)
{
    ITEM_MAP.put(Item.id, Item);
}

The getValue method is based on the String value that I will input in the onCreate method later

public String getValue(String id)
{   ProductItem value;
try{
    value = ITEM_MAP.get(id);//check here later

    Log.e("Value: ", value.toString());
    return "";  
}
catch(Exception ee)
{
    ee.printStackTrace();
}
    return "";
}

This is the class to initialize the variable and will be used in my save and retrieve value like mention just now:the name and id.

public static class ProductItem {//Instantiation of variable
    public String name;
    public String id;

    public ProductItem(String id,String name) {
        this.id = id;
        this.name = name;
    }
}

    /////*****////////

can ignore the MOBILE_OS since it is just for testing purpose to retrieve image

    static final String[] MOBILE_OS = new String[] { 
        "Samsung Galaxy S III 16GB", "Samsung Galaxy S IV Zoom","Samsung Galaxy Note 8.0 16GB", "Blackberry" };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
          final Intent intent = new Intent(this,ProductCollectionDetails.class);
          setContentView(R.layout.activity_product_collection);

          GridView gridview = (GridView) findViewById(R.id.productGridView);

          gridview.setAdapter(new ImageAdapter(this,MOBILE_OS)); 

          gridview.setOnItemClickListener(new OnItemClickListener() {
              public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
                  // Toast.makeText(ProductCollection.this, "" + MOBILE_OS[position], Toast.LENGTH_SHORT).show();

              //  Log.e("Item map value", ITEM_MAP.get(position).toString());
               //   for (Map.Entry<String,ProductItem> entry : ITEM_MAP.entrySet()) {

the getValue method calling here.

                     getValue(Integer.toString(position));
                //  }


                //   if((MOBILE_OS[position]).toString()== ITEM_MAP.get(position).toString())
                  //    {
                                //intent.putExtra(EXTRA_MESSAGE,(MOBILE_OS[position]).toString());
                                //startActivity(intent);
                   //   }
               }
            });


        if (savedInstanceState == null) {
            getFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment()).commit();
        }
    }

onResume and onPause method is just used to call the AsyncTask and clear the HashMap

@Override
protected void onResume()
{
    super.onResume();
    (new objectTransfer()).execute(null,null,null);
    //Log.e("Task Running", "AsyncTask");

}

@Override
protected void onPause()
{
    super.onPause();
    ITEM_MAP.clear();
}



    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.product_collection, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(
                    R.layout.fragment_product_collection, container, false);
            return rootView;
        }
    }

}

The logcat from my eclipse:

04-17 14:14:55.820: D/dalvikvm(14073): GC_FOR_ALLOC freed 124K, 27% free 6530K/8899K, paused 0ms
04-17 14:14:55.820: I/dalvikvm-heap(14073): Grow heap (frag case) to 10.931MB for 2524908-byte allocation
04-17 14:14:55.890: D/dalvikvm(14073): GC_CONCURRENT freed 1K, 22% free 8995K/11395K, paused 0ms+0ms
04-17 14:14:56.020: D/dalvikvm(14073): GC_FOR_ALLOC freed 2468K, 40% free 7629K/12547K, paused 0ms
04-17 14:14:56.140: I/PGA(14073): New SOCKET connection: bile_e_commerce (pid 14073, tid 14073)
04-17 14:14:59.960: D/dalvikvm(14073): GC_CONCURRENT freed 1259K, 34% free 8402K/12547K, paused 0ms+0ms
04-17 14:15:00.100: E/dalvikvm(14073): No JIT support for bytecode f0 at offsetPC 0
04-17 14:15:00.100: E/dalvikvm(14073): JIT implementation not found
04-17 14:15:00.100: I/dalvikvm(14073): codeGenBasicBlockJit returns negative number
04-17 14:15:00.100: E/dalvikvm(14073): No JIT support for bytecode f0 at offsetPC 0
04-17 14:15:00.100: E/dalvikvm(14073): JIT implementation not found
04-17 14:15:00.100: I/dalvikvm(14073): codeGenBasicBlockJit returns negative number
04-17 14:15:00.160: D/dalvikvm(14073): GC_FOR_ALLOC freed 540K, 24% free 9553K/12547K, paused 10ms
04-17 14:15:00.210: D/dalvikvm(14073): GC_FOR_ALLOC freed 1172K, 32% free 9056K/13315K, paused 10ms
04-17 14:15:00.210: I/dalvikvm-heap(14073): Grow heap (frag case) to 15.110MB for 4320012-byte allocation
04-17 14:15:00.310: D/dalvikvm(14073): GC_FOR_ALLOC freed <1K, 25% free 13274K/17539K, paused 90ms
04-17 14:15:00.330: D/dalvikvm(14073): GC_CONCURRENT freed 0K, 25% free 13274K/17539K, paused 0ms+0ms
04-17 14:15:00.350: D/dalvikvm(14073): GC_FOR_ALLOC freed 2K, 25% free 13282K/17539K, paused 0ms
04-17 14:15:00.360: I/dalvikvm-heap(14073): Grow heap (frag case) to 16.948MB for 1920012-byte allocation
04-17 14:15:00.370: D/dalvikvm(14073): GC_FOR_ALLOC freed <1K, 23% free 15156K/19459K, paused 10ms
04-17 14:15:00.390: D/dalvikvm(14073): GC_FOR_ALLOC freed 4221K, 44% free 10943K/19459K, paused 0ms
04-17 14:15:00.400: I/dalvikvm-heap(14073): Grow heap (frag case) to 14.978MB for 2250012-byte allocation
04-17 14:15:00.440: D/dalvikvm(14073): GC_CONCURRENT freed <1K, 33% free 13140K/19459K, paused 0ms+0ms
04-17 14:15:01.050: D/dalvikvm(14073): GC_CONCURRENT freed 3141K, 39% free 11952K/19459K, paused 0ms+0ms
04-17 14:15:04.030: W/System.err(14073): java.lang.NullPointerException
04-17 14:15:04.030: W/System.err(14073):    at com.example.mobile_e_commerce.ProductCollection.getValue(ProductCollection.java:162)
04-17 14:15:04.030: W/System.err(14073):    at com.example.mobile_e_commerce.ProductCollection$1.onItemClick(ProductCollection.java:202)
04-17 14:15:04.040: W/System.err(14073):    at android.widget.AdapterView.performItemClick(AdapterView.java:292)
04-17 14:15:04.040: W/System.err(14073):    at android.widget.AbsListView.performItemClick(AbsListView.java:1058)
04-17 14:15:04.040: W/System.err(14073):    at android.widget.AbsListView$PerformClick.run(AbsListView.java:2514)
04-17 14:15:04.040: W/System.err(14073):    at android.widget.AbsListView$1.run(AbsListView.java:3168)
04-17 14:15:04.040: W/System.err(14073):    at android.os.Handler.handleCallback(Handler.java:605)
04-17 14:15:04.040: W/System.err(14073):    at android.os.Handler.dispatchMessage(Handler.java:92)
04-17 14:15:04.040: W/System.err(14073):    at android.os.Looper.loop(Looper.java:137)
04-17 14:15:04.040: W/System.err(14073):    at android.app.ActivityThread.main(ActivityThread.java:4424)
04-17 14:15:04.040: W/System.err(14073):    at java.lang.reflect.Method.invokeNative(Native Method)
04-17 14:15:04.040: W/System.err(14073):    at java.lang.reflect.Method.invoke(Method.java:511)
04-17 14:15:04.040: W/System.err(14073):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:825)
04-17 14:15:04.040: W/System.err(14073):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:592)
04-17 14:15:04.040: W/System.err(14073):    at dalvik.system.NativeStart.main(Native Method)

Answer 1

Check your getValue() Method

Try this

public String getValue(String id)
{   
  ProductItem value;               
   try{           
  if(ITEM_MAP != null )               
    value = ITEM_MAP.get(id.trim());//check here later       
  if(value != null){         
    Log.e("Value: ", value.toString());        
}       
    return "";  
}
catch(Exception ee)
{
    ee.printStackTrace();
}
    return "";
}