I'm getting difficulties with storing JSON data to sqlite. This is actually the code that we am attempting to implement at this time. The JSON information is not particularly large with only 40 lines inside it.

The primary activity is:

public class DatabaseActivity extends Activity {
/** Called when the activity is first created. */

public DBAdapter
DBAdapter =new DBAdapter(this);

TextView txt;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Create a crude view - this should really be set via the layout resources  
// but since its an example saves declaring them in the XML.  
LinearLayout rootLayout = new LinearLayout(getApplicationContext());  
txt = new TextView(getApplicationContext());  
rootLayout.addView(txt);  
setContentView(rootLayout);  

// Set the text and call the connect function.  
txt.setText("Connecting..."); 
//call the method to run the data retreival
txt.setText(getServerData(KEY_13)); 

}

public static final String KEY_13 = "http://xxx.xxx.xxx/api/train.php";


private String getServerData(String returnString) {

InputStream is = null;

String result = "";
//the train line to send
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("code","A"));

//http post
try{
        HttpClient httpclient = new DefaultHttpClient();
        HttpPost httppost = new HttpPost(KEY_13);
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
        HttpResponse response = httpclient.execute(httppost);
        HttpEntity entity = response.getEntity();
        is = entity.getContent();

}catch(Exception e){
        Log.e("log_tag", "Error in http connection "+e.toString());
}

//convert response to string
try{
        BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        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());
}

//parse json data
try{
        JSONArray jArray = new JSONArray(result);
        for(int i=0;i<jArray.length();i++){
                JSONObject json_data = jArray.getJSONObject(i);
                DBAdapter.insertTrain(json_data.getString("id"),
                                    json_data.getString("code"),
                                    json_data.getString("station"),
                                    json_data.getString("platform"),
                                    json_data.getString("timetillstation"),
                                    json_data.getString("traindestination"),

                //Get an output to the screen
                returnString += "\n\t" + jArray.getJSONObject(i); 
        }
}catch(JSONException e){
        Log.e("log_tag", "Error parsing data "+e.toString());
}
return returnString; 
}    

}

The adapter is:

public class DBAdapter{
public static final String KEY_ID = "id";
public static final String KEY_Code = "code";
public static final String KEY_Station = "station";
public static final String KEY_Platform = "platform";
public static final String KEY_TimeTillStation = "timetillstation";
public static final String KEY_TrainDestination = "traindestination";
private static final String TAG = "DBAdapter";

private static final String DATABASE_NAME = "trains";
private static final String DATABASE_TABLE = "Mekerel";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_CREATE =
    "create table titles (id integer primary key, "
    + "code text not null,"
    + "station text not null,"
    + "platform text not null,"
    + "timetillstation text not null,"
    + "traindestination text not null);";

private final Context context; 

private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
  {
      this.context = ctx;
      DBHelper = new DatabaseHelper(context);
      this.db=DBHelper.getWritableDatabase();
  }

private static class DatabaseHelper extends SQLiteOpenHelper 
{
    DatabaseHelper(Context context) 
    {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }
    @Override
    public void onCreate(SQLiteDatabase db) 
    {
        db.execSQL(DATABASE_CREATE);        }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, 
    int newVersion) 
    {
        Log.w(TAG, "Upgrading database from version " + oldVersion 
                + " to "
                + newVersion + ", which will destroy all old data");
        db.execSQL("DROP TABLE IF EXISTS titles");
        onCreate(db);
    }
}    

//---opens the database---
public DBAdapter open() throws SQLException 
{
    db = DBHelper.getWritableDatabase();
    return this;
}
//---closes the database---    
public void close() 
{
    DBHelper.close();
}

//---insert a train into the database---
public long insertTrain(String id, String code, String station, String platform, String timetillstation, String traindestination) 
{
    ContentValues initialValues = new ContentValues();
    initialValues.put(KEY_ID, id);
    initialValues.put(KEY_Code, code);
    initialValues.put(KEY_Station, station);
    initialValues.put(KEY_Platform, platform);
    initialValues.put(KEY_TimeTillStation, timetillstation);
    initialValues.put(KEY_TrainDestination, traindestination);
    return db.insert(DATABASE_TABLE, null, initialValues);
}
//---retrieves all the ttrain---
public Cursor getAllTrains() 
{
    return db.query(DATABASE_TABLE, new String[] {
            KEY_ID,
            KEY_Code,
            KEY_Station,
            KEY_Platform,
            KEY_TimeTillStation,
            KEY_TrainDestination},
            null, 
            null, 
            null, 
            null, 
            null,
            null);
}
//---retrieves a particular train---
public Cursor getTrain(long id) throws SQLException 
{
    Cursor mCursor =
            db.query(true, DATABASE_TABLE, new String[] {
            KEY_ID,
            KEY_Code, 
            KEY_Station,
            KEY_Platform,
            KEY_TimeTillStation,
            KEY_TrainDestination}, 
        KEY_ID + "=" + id, 
        null,
        null, 
        null, 
        null, 
        null);
    if (mCursor != null) {
        mCursor.moveToFirst();
    }
    return mCursor;
}
//---updates a train---
public boolean updateTrain(long id, String code, String station, String platform, String timetillstation, String traindestination) 
{
    ContentValues args = new ContentValues();
    args.put(KEY_Code, code);
    args.put(KEY_Station, station);
    args.put(KEY_Platform, platform);
    args.put(KEY_TimeTillStation, timetillstation);
    args.put(KEY_TrainDestination, traindestination);
    return db.update(DATABASE_TABLE, args, 
                     KEY_ID + "=" + id, null) > 0;
}
}

I don't know what to do came from here as you will find still issues. The log cat shows the next:

12-04 12:43:09.691: E/AndroidRuntime(21334): FATAL EXCEPTION: main
12-04 12:43:09.691: E/AndroidRuntime(21334): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{ta.dabase/ta.dabase.DatabaseActivity}: java.lang.NullPointerException
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1680)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.app.ActivityThread.access$1500(ActivityThread.java:123)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.os.Handler.dispatchMessage(Handler.java:99)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.os.Looper.loop(Looper.java:130)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.app.ActivityThread.main(ActivityThread.java:3835)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at java.lang.reflect.Method.invokeNative(Native Method)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at java.lang.reflect.Method.invoke(Method.java:507)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at dalvik.system.NativeStart.main(Native Method)
12-04 12:43:09.691: E/AndroidRuntime(21334): Caused by: java.lang.NullPointerException
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:203)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:118)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at ta.dabase.DBAdapter.<init>(DBAdapter.java:43)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at ta.dabase.DatabaseActivity.<init>(DatabaseActivity.java:32)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at java.lang.Class.newInstanceImpl(Native Method)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at java.lang.Class.newInstance(Class.java:1409)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
12-04 12:43:09.691: E/AndroidRuntime(21334):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1672)
12-04 12:43:09.691: E/AndroidRuntime(21334):    ... 11 more

Finally, I'm wondering if anybody may help me with debugging in this way what and where you can place appropriate logging code to identify where code is certainly going wrong exactly? Thanks