JSON error Caused by: java.lang.NullPointerException
- by user3821853
im trying to make a register page on android using JSON.
everytime i press register button on avd, i get an error "unfortunately database has stopped".
i have a error on my logcat that i cannot understand.
this my code.
please someone help me.
this my register.java
import android.app.Activity;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.List;
public class Register extends Activity implements OnClickListener{
private EditText user, pass;
private Button mRegister;
// Progress Dialog
private ProgressDialog pDialog;
// JSON parser class
JSONParser jsonParser = new JSONParser();
//php register script
//localhost :
//testing on your device
//put your local ip instead, on windows, run CMD > ipconfig
//or in mac's terminal type ifconfig and look for the ip under en0 or en1
// private static final String REGISTER_URL = "http://xxx.xxx.x.x:1234/webservice/register.php";
//testing on Emulator:
private static final String REGISTER_URL = "http://10.0.2.2:1234/webservice/register.php";
//testing from a real server:
//private static final String REGISTER_URL = "http://www.mybringback.com/webservice/register.php";
//ids
private static final String TAG_SUCCESS = "success";
private static final String TAG_MESSAGE = "message";
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.register);
user = (EditText)findViewById(R.id.username);
pass = (EditText)findViewById(R.id.password);
mRegister = (Button)findViewById(R.id.register);
mRegister.setOnClickListener(this);
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new CreateUser().execute();
}
class CreateUser extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(Register.this);
pDialog.setMessage("Creating User...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected String doInBackground(String... args) {
// TODO Auto-generated method stub
// Check for success tag
int success;
String username = user.getText().toString();
String password = pass.getText().toString();
try {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("username", username));
params.add(new BasicNameValuePair("password", password));
Log.d("request!", "starting");
//Posting user data to script
JSONObject json = jsonParser.makeHttpRequest(
REGISTER_URL, "POST", params);
// full json response
Log.d("Registering attempt", json.toString());
// json success element
success = json.getInt(TAG_SUCCESS);
if (success == 1) {
Log.d("User Created!", json.toString());
finish();
return json.getString(TAG_MESSAGE);
}else{
Log.d("Registering Failure!", json.getString(TAG_MESSAGE));
return json.getString(TAG_MESSAGE);
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String file_url) {
// dismiss the dialog once product deleted
pDialog.dismiss();
if (file_url != null){
Toast.makeText(Register.this, file_url, Toast.LENGTH_LONG).show();
}
}
}
}
this is JSONparser.java
import android.util.Log;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URLEncodedUtils;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.List;
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(final String url) {
// Making HTTP request
try {
// Construct the client and the HTTP request.
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
// Execute the POST request and store the response locally.
HttpResponse httpResponse = httpClient.execute(httpPost);
// Extract data from the response.
HttpEntity httpEntity = httpResponse.getEntity();
// Open an inputStream with the data content.
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
// Create a BufferedReader to parse through the inputStream.
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
// Declare a string builder to help with the parsing.
StringBuilder sb = new StringBuilder();
// Declare a string to store the JSON object data in string form.
String line = null;
// Build the string until null.
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
// Close the input stream.
is.close();
// Convert the string builder data to an actual string.
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// Try to parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// Return the JSON Object.
return jObj;
}
// function get json from url
// by making HTTP POST or GET mehtod
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
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();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
and this my error
08-18 23:40:02.381 2000-2018/com.example.blackcustomzier.database E/Buffer Error? Error converting result java.lang.NullPointerException: lock == null
08-18 23:40:02.381 2000-2018/com.example.blackcustomzier.database E/JSON Parser? Error parsing data org.json.JSONException: End of input at character 0 of
08-18 23:40:02.391 2000-2018/com.example.blackcustomzier.database W/dalvikvm? threadid=15: thread exiting with uncaught exception (group=0xb0f37648)
08-18 23:40:02.391 2000-2018/com.example.blackcustomzier.database E/AndroidRuntime? FATAL EXCEPTION: AsyncTask #4
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:299)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
at java.util.concurrent.FutureTask.run(FutureTask.java:239)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:841)
Caused by: java.lang.NullPointerException
at com.example.blackcustomzier.database.Register$CreateUser.doInBackground(Register.java:108)
at com.example.blackcustomzier.database.Register$CreateUser.doInBackground(Register.java:74)
at android.os.AsyncTask$2.call(AsyncTask.java:287)
at java.util.concurrent.FutureTask.run(FutureTask.java:234)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:841)
08-18 23:40:02.501 2000-2000/com.example.blackcustomzier.database W/EGL_emulation? eglSurfaceAttrib not implemented
08-18 23:40:02.591 2000-2000/com.example.blackcustomzier.database W/EGL_emulation? eglSurfaceAttrib not implemented
08-18 23:40:02.981 2000-2000/com.example.blackcustomzier.database E/WindowManager? Activity com.example.blackcustomzier.database.Register has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b1294c60 V.E..... R......D 0,0-1026,288} that was originally added here
android.view.WindowLeaked: Activity com.example.blackcustomzier.database.Register has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b1294c60 V.E..... R......D 0,0-1026,288} that was originally added here
at android.view.ViewRootImpl.<init>(ViewRootImpl.java:345)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:239)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
at android.app.Dialog.show(Dialog.java:281)
at com.example.blackcustomzier.database.Register$CreateUser.onPreExecute(Register.java:85)
at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
at android.os.AsyncTask.execute(AsyncTask.java:534)
at com.example.blackcustomzier.database.Register.onClick(Register.java:70)
at android.view.View.performClick(View.java:4240)
at android.view.View.onKeyUp(View.java:7928)
at android.widget.TextView.onKeyUp(TextView.java:5606)
at android.view.KeyEvent.dispatch(KeyEvent.java:2647)
at android.view.View.dispatchKeyEvent(View.java:7343)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393)
at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1933)
at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1408)
at android.app.Activity.dispatchKeyEvent(Activity.java:2384)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1860)
at android.view.ViewRootImpl$ViewPostImeInputStage.processKeyEvent(ViewRootImpl.java:3791)
at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:3774)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3379)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3429)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3398)
at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3483)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3406)
at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:3540)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3379)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3429)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3398)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3406)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3379)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3429)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3398)
at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3516)
at android.view.ViewRootImpl$ImeInputStage.onFinishedInputEvent(ViewRootImpl.java:3666)
at android.view.inputmethod.InputMethodManager$PendingEvent.run(InputMethodManager.java:1982)
at android.view.inputmethod.InputMethodManager.invokeFinishedInputEventCallback(InputMethodManager.java:1698)
at android.view.inputmethod.InputMethodManager.finishedInputEvent(InputMethodManager.java:1689)
at android.view.inputmethod.InputMethodManager$ImeInputEventSender.onInputEventFinished(InputMethodManager.java:1959)
at android.view.InputEventSender.dispatchInputEventFinished(InputEventSender.java:141)
at android.os.MessageQueue.nativePollOnce(Native Method)
at android.os.MessageQueue.next(MessageQueue.java:132)
at android.os.Looper.loop(Looper.java:124)
at android.app.ActivityThread.main(ActivityThread.java:5103)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCal
please help me to solve this thx
