Android的错误转换结果显示java.lang.NullPointerException [英] Android error converting result java.lang.nullpointerexception
问题描述
我想创建Android中简单的登录和注册活动。 我收到错误
错误转换结果显示java.lang.NullPointerException,错误解析 数据org.json.JSONException。
下面是我的code: JSONPARSER
公共类JSONParser {
静态的InputStream是= NULL;
静态的JSONObject jObj = NULL;
静态JSON字符串=;
//构造
公共JSONParser(){
}
//功能得到URL JSON
//通过HTTP POST或GET方法
公众的JSONObject makeHtt prequest(URL字符串,字符串的方法,
名单<的NameValuePair> PARAMS){
//使HTTP请求
尝试 {
//检查请求的方法
如果(方法==POST){
//请求方法是POST
// defaultHttpClient
DefaultHttpClient的HttpClient =新DefaultHttpClient();
HttpPost httpPost =新HttpPost(URL);
httpPost.setEntity(新UrlEn codedFormEntity(PARAMS));
HTT presponse HTT presponse = httpClient.execute(httpPost);
HttpEntity httpEntity = HTT presponse.getEntity();
是= httpEntity.getContent();
}否则,如果(方法==GET){
//请求方法是GET
DefaultHttpClient的HttpClient =新DefaultHttpClient();
字符串中的paramString = URLEn codedUtils.format(PARAMS,UTF-8);
网址+ =? +中的paramString;
HTTPGET HTTPGET =新HTTPGET(URL);
HTT presponse HTT presponse = httpClient.execute(HTTPGET);
HttpEntity httpEntity = HTT presponse.getEntity();
是= httpEntity.getContent();
}
}赶上(UnsupportedEncodingException E){
e.printStackTrace();
}赶上(ClientProtocolException E){
e.printStackTrace();
}赶上(IOException异常E){
e.printStackTrace();
}
尝试 {
的BufferedReader读卡器=新的BufferedReader(新的InputStreamReader(
是,ISO-8859-1),8);
StringBuilder的SB =新的StringBuilder();
串线= NULL;
而((行= reader.readLine())!= NULL){
sb.append(行+\ N);
}
is.close();
JSON = sb.toString();
}赶上(例外五){
Log.e(缓冲区错误,转换的结果错误+ e.toString());
}
//尝试解析字符串到一个JSON对象
尝试 {
jObj =新的JSONObject(JSON);
}赶上(JSONException E){
Log.e(JSON解析器,错误分析数据+ e.toString());
}
//返回JSON字符串
返回jObj;
}
}
USERFUNCTIONS:
公共类UserFunctions {
私人JSONParser jsonParser;
//测试在本地主机使用WAMP或XAMPP
//使用http://10.0.2.2/连接到本地主机即http://本地主机/
私有静态字符串loginURL =http://49.249.85.221/android_api/;
私有静态字符串REGISTERURL =http://49.249.85.221/android_api/;
私有静态字符串login_tag =登陆;
私有静态字符串register_tag =注册;
//构造
公共UserFunctions(){
jsonParser =新JSONParser();
}
/ **
*功能使登录请求
* @参数电子邮件
* @参数密码
* * /
公众的JSONObject loginUser(字符串email,字符串密码){
//大厦参数
名单<的NameValuePair> PARAMS =新的ArrayList<的NameValuePair>();
params.add(新BasicNameValuePair(标签,login_tag));
params.add(新BasicNameValuePair(邮件,邮件));
params.add(新BasicNameValuePair(密码,密码));
字符串方法=新的String();
JSONObject的JSON = jsonParser.makeHtt prequest(loginURL,法,则params);
//返回JSON
// Log.e(JSON,json.toString());
返回JSON;
}
/ **
*功能使登录请求
* @参数名称
* @参数电子邮件
* @参数密码
* * /
公众的JSONObject registerUser(字符串名称,字符串email,字符串密码){
//大厦参数
名单<的NameValuePair> PARAMS =新的ArrayList<的NameValuePair>();
params.add(新BasicNameValuePair(标签,register_tag));
params.add(新BasicNameValuePair(姓名,名字));
params.add(新BasicNameValuePair(邮件,邮件));
params.add(新BasicNameValuePair(密码,密码));
字符串方法=新的String();
//获取JSON对象
JSONObject的JSON = jsonParser.makeHtt prequest(REGISTERURL,法,则params);
//返回JSON
返回JSON;
}
/ **
*函数来获取登录状态
* * /
公共布尔isUserLoggedIn(上下文的背景下){
数据库处理器DB =新的数据库处理器(上下文);
诠释计数= db.getRowCount();
如果(计数大于0){
//用户登录
返回true;
}
返回false;
}
/ **
*功能注销用户
*复位数据库
* * /
公共布尔logoutUser(上下文的背景下){
数据库处理器DB =新的数据库处理器(上下文);
db.resetTables();
返回true;
}
}
REGISTERACTIVITY:
公共类RegisterActivity延伸活动{
按钮btnRegister;
按钮btnLinkToLogin;
的EditText inputFullName;
的EditText inputEmail;
的EditText控件inputPassword;
TextView的registerErrorMsg;
// JSON响应节点名称
私有静态字符串KEY_SUCCESS =成功;
私有静态字符串KEY_ERROR =错误;
私有静态字符串KEY_ERROR_MSG =ERROR_MSG;
私有静态字符串KEY_UID =UID;
私有静态字符串KEY_NAME =名;
私有静态字符串KEY_EMAIL =电子邮件;
私有静态字符串KEY_CREATED_AT =created_at;
私有类MyAsyncTask扩展的AsyncTask<字符串,无效的JSONObject> {
受保护的JSONObject doInBackground(字符串... PARAMS){
UserFunctions userFunction =新UserFunctions();
如果(params.length!= 3)
返回null;
的JSONObject JSON = userFunction.registerUser(PARAMS [0],则params [1],则params [2]);
返回JSON;
}
保护无效onPostExecute(JSONObject的JSON){
//检查登录响应
尝试 {
如果(JSON = NULL和放大器;!&安培;!json.getString(KEY_SUCCESS)= NULL){
registerErrorMsg.setText();
字符串解析度= json.getString(KEY_SUCCESS);
如果(的Integer.parseInt(RES)== 1){
//用户成功registred
在SQLite数据库//存储用户信息
数据库处理器DB =新的数据库处理器(getApplicationContext());
JSONObject的json_user = json.getJSONObject(用户);
在数据库//清除所有previous数据
UserFunctions userFunction =新UserFunctions();
userFunction.logoutUser(getApplicationContext());
db.addUser(json_user.getString(KEY_NAME),json_user.getString(KEY_EMAIL),json.getString(KEY_UID),json_user.getString(KEY_CREATED_AT));
//启动仪表盘屏幕
仪表盘意图=新的意图(getApplicationContext(),DashboardActivity.class);
//关闭所有的观点发起仪表板前,
dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(仪表盘);
//关闭注册画面
完();
}其他{
//登记错误
registerErrorMsg.setText(发生错误登记);
}
}
}赶上(JSONException E){
e.printStackTrace();
}
}
}
@覆盖
公共无效的onCreate(包savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.register);
//导入所有资产如按钮,文本字段
inputFullName =(EditText上)findViewById(R.id.registerName);
inputEmail =(EditText上)findViewById(R.id.registerEmail);
控件inputPassword =(EditText上)findViewById(R.id.registerPassword);
btnRegister =(按钮)findViewById(R.id.btnRegister);
btnLinkToLogin =(按钮)findViewById(R.id.btnLinkToLoginScreen);
registerErrorMsg =(TextView中)findViewById(R.id.register_error);
//注册按钮点击事件
btnRegister.setOnClickListener(新View.OnClickListener(){
公共无效的onClick(视图查看){
字符串名称= inputFullName.getText()的toString()。
。字符串email = inputEmail.getText()的toString();
。字符串password = inputPassword.getText()的toString();
新MyAsyncTask()执行(姓名,电子邮件,密码)。
UserFunctions userFunction =新UserFunctions();
JSONObject的JSON = userFunction.registerUser(姓名,电子邮件,密码);
//检查登录响应
尝试 {
如果(json.getString(KEY_SUCCESS)!= NULL){
registerErrorMsg.setText();
字符串解析度= json.getString(KEY_SUCCESS);
如果(的Integer.parseInt(RES)== 1){
//用户成功registred
在SQLite数据库//存储用户信息
数据库处理器DB =新的数据库处理器(getApplicationContext());
JSONObject的json_user = json.getJSONObject(用户);
在数据库//清除所有previous数据
userFunction.logoutUser(getApplicationContext());
db.addUser(json_user.getString(KEY_NAME),json_user.getString(KEY_EMAIL),json.getString(KEY_UID),json_user.getString(KEY_CREATED_AT));
//启动仪表盘屏幕
仪表盘意图=新的意图(getApplicationContext(),DashboardActivity.class);
//关闭所有的观点发起仪表板前,
dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(仪表盘);
//关闭注册画面
完();
}其他{
//登记错误
registerErrorMsg.setText(发生错误登记);
}
}
}赶上(JSONException E){
e.printStackTrace();
}
}
});
//链接登录屏幕
btnLinkToLogin.setOnClickListener(新View.OnClickListener(){
公共无效的onClick(视图查看){
意图I =新的意图(getApplicationContext()
LoginActivity.class);
startActivity(ⅰ);
//关闭注册查看
完();
}
});
}
}
当我运行调试它指的行如果(json.getString(KEY_SUCCESS)!= NULL)
在RegisterActivity。我无能,在那里我可能是错的。请指导我在此。
logcat的:
10-28 22:40:27.422:D / dalvikvm(373):GC_EXTERNAL_ALLOC释放78K,52%免费2599K / 5379K,外部897K / 1038K,暂停190ms
10-28 22:40:32.000:W / KeyCharacterMap(373):没有键盘ID 0
10-28 22:40:32.000:W / KeyCharacterMap(373):使用默认的键盘对应:/system/usr/keychars/qwerty.kcm.bin
10-28 22:40:45.879:E /缓存器的错误(373):错误转换结果显示java.lang.NullPointerException
10-28 22:40:45.899:E /缓存器的错误(373):错误转换结果显示java.lang.NullPointerException
10-28 22:40:45.983:E / JSON解析器(373):错误分析数据org.json.JSONException:输入的字符0结束
10-28 22:40:45.989:D / AndroidRuntime(373):关闭虚拟机
10-28 22:40:45.989:W / dalvikvm(373):主题ID = 1:螺纹退出与未捕获的异常(组= 0x40015560)
10-28 22:40:46.049:E / AndroidRuntime(373):致命异常:主要
10-28 22:40:46.049:E / AndroidRuntime(373):显示java.lang.NullPointerException
10-28 22:40:46.049:E / AndroidRuntime(373):在com.example.androidhive.RegisterActivity $ 1.onClick(RegisterActivity.java:112)
10-28 22:40:46.049:E / AndroidRuntime(373):在android.view.View.performClick(View.java:2485)
10-28 22:40:46.049:E / AndroidRuntime(373):在android.view.View $ PerformClick.run(View.java:9080)
10-28 22:40:46.049:E / AndroidRuntime(373):在android.os.Handler.handleCallback(Handler.java:587)
10-28 22:40:46.049:E / AndroidRuntime(373):在android.os.Handler.dispatchMessage(Handler.java:92)
10-28 22:40:46.049:E / AndroidRuntime(373):在android.os.Looper.loop(Looper.java:123)
10-28 22:40:46.049:E / AndroidRuntime(373):在android.app.ActivityThread.main(ActivityThread.java:3683)
10-28 22:40:46.049:E / AndroidRuntime(373):在java.lang.reflect.Method.invokeNative(本机方法)
10-28 22:40:46.049:E / AndroidRuntime(373):在java.lang.reflect.Method.invoke(Method.java:507)
10-28 22:40:46.049:E / AndroidRuntime(373):在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:839)
10-28 22:40:46.049:E / AndroidRuntime(373):位于c om.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
10-28 22:40:46.049:E / AndroidRuntime(373):在dalvik.system.NativeStart.main(本机方法)
10-28 22:40:46.309:E / JSON解析器(373):错误分析数据org.json.JSONException:输入的字符0结束
10-28 22:40:50.289:I /处理(373):发送信号。 PID:373 SIG:9
目前的主要问题是落实马丁提出的解决方案后解决。 现在我面临着一些其他错误。 logcat的连接如下:
10-28 23:17:19.183:D / dalvikvm(449):GC_EXTERNAL_ALLOC释放78K,52%免费2599K / 5379K,外部897K / 1038K,暂停232ms
10-28 23:17:23.259:W / KeyCharacterMap(449):没有键盘ID 0
10-28 23:17:23.269:W / KeyCharacterMap(449):使用默认的键盘对应:/system/usr/keychars/qwerty.kcm.bin
10-28 23:17:46.379:E /缓存器的错误(449):错误转换结果显示java.lang.NullPointerException
10-28 23:17:46.389:E /缓存器的错误(449):错误转换结果显示java.lang.NullPointerException
10-28 23:17:46.389:E / JSON解析器(449):错误分析数据org.json.JSONException:输入的字符0结束
10-28 23:17:46.409:E / JSON解析器(449):错误分析数据org.json.JSONException:输入的字符0结束
这可能是因为关键不存在一样,要求json.getString之前做到这一点(钥匙);方法:
的JSONObject JSON = yourJSON;
如果(JSON = NULL和放大器;!&安培;!json.isNull(KEY_SUCCESS)){
// Wahetever你需要
字符串值= json.getString(KEY_SUCCESS);
如果(值=空&安培;!&安培; value.length大于0){
//你会掉下这里只如果有一个值...
}
}
请注意,您首先需要确保的关键实际存在,otherway它可以抛出一个JSONException ...
希望这有助于...
商祺!
I am trying to create a simple login and registration activity in Android. I am getting the errors
Error converting result java.lang.nullpointerexception,error parsing data org.json.JSONException.
Below is my code : JSONPARSER
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET method
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;
}
}
USERFUNCTIONS:
public class UserFunctions {
private JSONParser jsonParser;
// Testing in localhost using wamp or xampp
// use http://10.0.2.2/ to connect to your localhost ie http://localhost/
private static String loginURL = "http://49.249.85.221/android_api/";
private static String registerURL = "http://49.249.85.221/android_api/";
private static String login_tag = "login";
private static String register_tag = "register";
// constructor
public UserFunctions(){
jsonParser = new JSONParser();
}
/**
* function make Login Request
* @param email
* @param password
* */
public JSONObject loginUser(String email, String password){
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("tag", login_tag));
params.add(new BasicNameValuePair("email", email));
params.add(new BasicNameValuePair("password", password));
String method=new String();
JSONObject json = jsonParser.makeHttpRequest(loginURL,method, params);
// return json
// Log.e("JSON", json.toString());
return json;
}
/**
* function make Login Request
* @param name
* @param email
* @param password
* */
public JSONObject registerUser(String name, String email, String password){
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("tag", register_tag));
params.add(new BasicNameValuePair("name", name));
params.add(new BasicNameValuePair("email", email));
params.add(new BasicNameValuePair("password", password));
String method=new String();
// getting JSON Object
JSONObject json = jsonParser.makeHttpRequest(registerURL,method, params);
// return json
return json;
}
/**
* Function get Login status
* */
public boolean isUserLoggedIn(Context context){
DatabaseHandler db = new DatabaseHandler(context);
int count = db.getRowCount();
if(count > 0){
// user logged in
return true;
}
return false;
}
/**
* Function to logout user
* Reset Database
* */
public boolean logoutUser(Context context){
DatabaseHandler db = new DatabaseHandler(context);
db.resetTables();
return true;
}
}
REGISTERACTIVITY:
public class RegisterActivity extends Activity {
Button btnRegister;
Button btnLinkToLogin;
EditText inputFullName;
EditText inputEmail;
EditText inputPassword;
TextView registerErrorMsg;
// JSON Response node names
private static String KEY_SUCCESS = "success";
private static String KEY_ERROR = "error";
private static String KEY_ERROR_MSG = "error_msg";
private static String KEY_UID = "uid";
private static String KEY_NAME = "name";
private static String KEY_EMAIL = "email";
private static String KEY_CREATED_AT = "created_at";
private class MyAsyncTask extends AsyncTask<String, Void, JSONObject> {
protected JSONObject doInBackground(String... params) {
UserFunctions userFunction = new UserFunctions();
if (params.length != 3)
return null;
JSONObject json = userFunction.registerUser(params[0], params[1], params[2]);
return json;
}
protected void onPostExecute(JSONObject json) {
// check for login response
try {
if (json != null && json.getString(KEY_SUCCESS) != null) {
registerErrorMsg.setText("");
String res = json.getString(KEY_SUCCESS);
if(Integer.parseInt(res) == 1){
// user successfully registred
// Store user details in SQLite Database
DatabaseHandler db = new DatabaseHandler(getApplicationContext());
JSONObject json_user = json.getJSONObject("user");
// Clear all previous data in database
UserFunctions userFunction = new UserFunctions();
userFunction.logoutUser(getApplicationContext());
db.addUser(json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL), json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT));
// Launch Dashboard Screen
Intent dashboard = new Intent(getApplicationContext(), DashboardActivity.class);
// Close all views before launching Dashboard
dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(dashboard);
// Close Registration Screen
finish();
}else{
// Error in registration
registerErrorMsg.setText("Error occured in registration");
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.register);
// Importing all assets like buttons, text fields
inputFullName = (EditText) findViewById(R.id.registerName);
inputEmail = (EditText) findViewById(R.id.registerEmail);
inputPassword = (EditText) findViewById(R.id.registerPassword);
btnRegister = (Button) findViewById(R.id.btnRegister);
btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen);
registerErrorMsg = (TextView) findViewById(R.id.register_error);
// Register Button Click event
btnRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
String name = inputFullName.getText().toString();
String email = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
new MyAsyncTask().execute(name, email, password);
UserFunctions userFunction = new UserFunctions();
JSONObject json = userFunction.registerUser(name, email, password);
// check for login response
try {
if (json.getString(KEY_SUCCESS) != null) {
registerErrorMsg.setText("");
String res = json.getString(KEY_SUCCESS);
if(Integer.parseInt(res) == 1){
// user successfully registred
// Store user details in SQLite Database
DatabaseHandler db = new DatabaseHandler(getApplicationContext());
JSONObject json_user = json.getJSONObject("user");
// Clear all previous data in database
userFunction.logoutUser(getApplicationContext());
db.addUser(json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL), json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT));
// Launch Dashboard Screen
Intent dashboard = new Intent(getApplicationContext(), DashboardActivity.class);
// Close all views before launching Dashboard
dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(dashboard);
// Close Registration Screen
finish();
}else{
// Error in registration
registerErrorMsg.setText("Error occured in registration");
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
// Link to Login Screen
btnLinkToLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),
LoginActivity.class);
startActivity(i);
// Close Registration View
finish();
}
});
}
}
When I ran debugger it pointed to the line if (json.getString(KEY_SUCCESS) != null)
in RegisterActivity. I am clueless as to where I might be wrong. Please guide me on this.
LOGCAT:
10-28 22:40:27.422: D/dalvikvm(373): GC_EXTERNAL_ALLOC freed 78K, 52% free 2599K/5379K, external 897K/1038K, paused 190ms
10-28 22:40:32.000: W/KeyCharacterMap(373): No keyboard for id 0
10-28 22:40:32.000: W/KeyCharacterMap(373): Using default keymap: /system/usr/keychars/qwerty.kcm.bin
10-28 22:40:45.879: E/Buffer Error(373): Error converting result java.lang.NullPointerException
10-28 22:40:45.899: E/Buffer Error(373): Error converting result java.lang.NullPointerException
10-28 22:40:45.983: E/JSON Parser(373): Error parsing data org.json.JSONException: End of input at character 0 of
10-28 22:40:45.989: D/AndroidRuntime(373): Shutting down VM
10-28 22:40:45.989: W/dalvikvm(373): threadid=1: thread exiting with uncaught exception (group=0x40015560)
10-28 22:40:46.049: E/AndroidRuntime(373): FATAL EXCEPTION: main
10-28 22:40:46.049: E/AndroidRuntime(373): java.lang.NullPointerException
10-28 22:40:46.049: E/AndroidRuntime(373): at com.example.androidhive.RegisterActivity$1.onClick (RegisterActivity.java:112)
10-28 22:40:46.049: E/AndroidRuntime(373): at android.view.View.performClick(View.java:2485)
10-28 22:40:46.049: E/AndroidRuntime(373): at android.view.View$PerformClick.run(View.java:9080)
10-28 22:40:46.049: E/AndroidRuntime(373): at android.os.Handler.handleCallback(Handler.java:587)
10-28 22:40:46.049: E/AndroidRuntime(373): at android.os.Handler.dispatchMessage(Handler.java:92)
10-28 22:40:46.049: E/AndroidRuntime(373): at android.os.Looper.loop(Looper.java:123)
10-28 22:40:46.049: E/AndroidRuntime(373): at android.app.ActivityThread.main(ActivityThread.java:3683)
10-28 22:40:46.049: E/AndroidRuntime(373): at java.lang.reflect.Method.invokeNative(Native Method)
10-28 22:40:46.049: E/AndroidRuntime(373): at java.lang.reflect.Method.invoke(Method.java:507)
10-28 22:40:46.049: E/AndroidRuntime(373): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:839)
10-28 22:40:46.049: E/AndroidRuntime(373): at c om.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
10-28 22:40:46.049: E/AndroidRuntime(373): at dalvik.system.NativeStart.main(Native Method)
10-28 22:40:46.309: E/JSON Parser(373): Error parsing data org.json.JSONException: End of input at character 0 of
10-28 22:40:50.289: I/Process(373): Sending signal. PID: 373 SIG: 9
The main issue is resolved after implementing the solution suggested by Martin. I am facing some other errors now. LOGCAT is attached below.
10-28 23:17:19.183: D/dalvikvm(449): GC_EXTERNAL_ALLOC freed 78K, 52% free 2599K/5379K, external 897K/1038K, paused 232ms
10-28 23:17:23.259: W/KeyCharacterMap(449): No keyboard for id 0
10-28 23:17:23.269: W/KeyCharacterMap(449): Using default keymap: /system/usr/keychars/qwerty.kcm.bin
10-28 23:17:46.379: E/Buffer Error(449): Error converting result java.lang.NullPointerException
10-28 23:17:46.389: E/Buffer Error(449): Error converting result java.lang.NullPointerException
10-28 23:17:46.389: E/JSON Parser(449): Error parsing data org.json.JSONException: End of input at character 0 of
10-28 23:17:46.409: E/JSON Parser(449): Error parsing data org.json.JSONException: End of input at character 0 of
That might be because the key not even exist, do this before calling json.getString("key"); method:
JSONObject json = yourJSON;
if(json != null && !json.isNull(KEY_SUCCESS)){
//Wahetever you need
String value = json.getString(KEY_SUCCESS);
if(value != null && value.length > 0){
//You will fall here only if there's a value...
}
}
Notice that you first need to make sure that the key actually exist, otherway it could throw a JSONException...
Hope this helps...
Regards!
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