Java android应用程序崩溃并在注册时出错
我正在使用Android Studio开发注册应用程序,但是一旦用户尝试注册应用程序时只说注册错误,LogCat没有给出任何错误,以及调试应用程序时,我仍然没有收到任何错误 请您帮助并告诉我哪里出了问题,因为代码是正确的,因为它在几个月前还在工作,但由于我度假回来,它只说“注册时出错” 用户数据被输入数据库,但它不允许用户进入下一个活动,因为它说“注册时出错”。请问你能帮忙或提供建议吗 LogCatJava android应用程序崩溃并在注册时出错,java,android,json,Java,Android,Json,我正在使用Android Studio开发注册应用程序,但是一旦用户尝试注册应用程序时只说注册错误,LogCat没有给出任何错误,以及调试应用程序时,我仍然没有收到任何错误 请您帮助并告诉我哪里出了问题,因为代码是正确的,因为它在几个月前还在工作,但由于我度假回来,它只说“注册时出错” 用户数据被输入数据库,但它不允许用户进入下一个活动,因为它说“注册时出错”。请问你能帮忙或提供建议吗 LogCat 01-07 15:14:42.933 2161-4203/com.Oakland E/JSO
01-07 15:14:42.933 2161-4203/com.Oakland E/JSON Parser: Error parsing data org.json.JSONException: Value 2016-01-07 of type java.lang.String cannot be converted to JSONObject
01-07 15:14:42.938 2161-2161/com.Oakland E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.Oakland, PID: 2161
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.getString(java.lang.String)' on a null object reference
at com.Oakland.Register$ProcessRegister.onPostExecute(Register.java:211)
at com.Oakland.Register$ProcessRegister.onPostExecute(Register.java:171)
第211行-if(json.getString(KEY_SUCCESS)!=null){
Register.Java
@Override
protected JSONObject doInBackground(String... args) {
UserFunctions userFunction = new UserFunctions();
JSONObject json = userFunction.registerUser(fname, lname, email, uname, password);
return json;
}
@Override
protected void onPostExecute(JSONObject json) {
try {
if (json != null && json.getString(KEY_SUCCESS) != null) {
if (json != null && json.getString(KEY_SUCCESS) != null)
registerErrorMsg.setText("");
String res = json.getString(KEY_SUCCESS);
String red = json.getString(KEY_ERROR);
if(Integer.parseInt(res) == 1){
pDialog.setTitle("Getting Data");
pDialog.setMessage("Loading Info");
registerErrorMsg.setText("Successfully Registered");
DatabaseHandler db = new DatabaseHandler(getApplicationContext());
JSONObject json_user = json.getJSONObject("user");
/**
* Removes all the previous data in the SQlite database
**/
UserFunctions logout = new UserFunctions();
logout.logoutUser(getApplicationContext());
db.addUser(json_user.getString(KEY_FIRSTNAME),json_user.getString(KEY_LASTNAME),json_user.getString(KEY_EMAIL),json_user.getString(KEY_USERNAME),json_user.getString(KEY_UID),json_user.getString(KEY_CREATED_AT));
/**
* Stores registered data in SQlite Database
* Launch Registered screen
**/
Intent registered = new Intent(getApplicationContext(), Registered.class);
/**
* Close all views before launching Registered screen
**/
registered.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
pDialog.dismiss();
startActivity(registered);
finish();
}
else if (Integer.parseInt(red) ==2){
pDialog.dismiss();
registerErrorMsg.setText("User already exists");
}
else if (Integer.parseInt(red) ==3){
pDialog.dismiss();
registerErrorMsg.setText("Invalid Email id");
}
}
else{
pDialog.dismiss();
registerErrorMsg.setText("Error occurred in registration");
}
} catch (JSONException e) {
e.printStackTrace();
}
}}
public void NetAsync(View view){
new NetCheck().execute();
}}
Java
//URL of the PHP API
private static String registerURL = "http://10.0.2.2/Register_api/";
private static String register_tag = "register";
/**
* Function to Register
**/
public JSONObject registerUser(String fname, String lname, String email, String uname, String password){
// Building Parameters
List params = new ArrayList();
params.add(new BasicNameValuePair("tag", register_tag));
params.add(new BasicNameValuePair("fname", fname));
params.add(new BasicNameValuePair("lname", lname));
params.add(new BasicNameValuePair("email", email));
params.add(new BasicNameValuePair("uname", uname));
params.add(new BasicNameValuePair("password", password));
JSONObject json = jsonParser.getJSONFromUrl(registerURL,params);
return json;
}
Jsonpasar.java
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) {
// Making HTTP request
try {
// 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();
} 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();
Log.e("JSON", json);
} 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;
}
}
公共类JSONParser{
静态InputStream为空;
静态JSONObject jObj=null;
静态字符串json=“”;
//建造师
公共JSONParser(){
}
公共JSONObject getJSONFromUrl(字符串url,列表参数){
//发出HTTP请求
试一试{
//defaultHttpClient
DefaultHttpClient httpClient=新的DefaultHttpClient();
HttpPost HttpPost=新的HttpPost(url);
setEntity(新的UrlEncodedFormEntity(参数));
HttpResponse HttpResponse=httpClient.execute(httpPost);
HttpEntity HttpEntity=httpResponse.getEntity();
is=httpEntity.getContent();
}捕获(不支持的编码异常e){
e、 printStackTrace();
}捕获(客户端协议例外e){
e、 printStackTrace();
}捕获(IOE异常){
e、 printStackTrace();
}
试一试{
BufferedReader reader=新的BufferedReader(新的InputStreamReader(
is,“iso-8859-1”),8);
StringBuilder sb=新的StringBuilder();
字符串行=null;
而((line=reader.readLine())!=null){
sb.追加(第+行“\n”);
}
is.close();
json=sb.toString();
Log.e(“JSON”,JSON);
}捕获(例外e){
Log.e(“缓冲区错误”,“错误转换结果”+e.toString());
}
//尝试将字符串解析为JSON对象
试一试{
jObj=新的JSONObject(json);
}捕获(JSONException e){
Log.e(“JSON解析器”,“错误解析数据”+e.toString());
}
//返回JSON字符串
返回jObj;
}
}
DatabaseHandler.java
public class DatabaseHandler extends SQLiteOpenHelper {
// All Static variables
// Database Version
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "cloud_contacts";
// Login table name
private static final String TABLE_LOGIN = "login";
// Login Table Columns names
private static final String KEY_ID = "id";
private static final String KEY_FIRSTNAME = "fname";
private static final String KEY_LASTNAME = "lname";
private static final String KEY_EMAIL = "email";
private static final String KEY_USERNAME = "uname";
private static final String KEY_UID = "uid";
private static final String KEY_CREATED_AT = "created_at";
public DatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
// Creating Tables
@Override
public void onCreate(SQLiteDatabase db) {
String CREATE_LOGIN_TABLE = "CREATE TABLE " + TABLE_LOGIN + "("
+ KEY_ID + " INTEGER PRIMARY KEY,"
+ KEY_FIRSTNAME + " TEXT,"
+ KEY_LASTNAME + " TEXT,"
+ KEY_EMAIL + " TEXT UNIQUE,"
+ KEY_USERNAME + " TEXT,"
+ KEY_UID + " TEXT,"
+ KEY_CREATED_AT + " TEXT" + ")";
db.execSQL(CREATE_LOGIN_TABLE);
}
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_LOGIN);
// Create tables again
onCreate(db);
}
/**
* Storing user details in database
* */
public void addUser(String fname, String lname, String email, String uname, String uid, String created_at) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_FIRSTNAME, fname); // FirstName
values.put(KEY_LASTNAME, lname); // LastName
values.put(KEY_EMAIL, email); // Email
values.put(KEY_USERNAME, uname); // UserName
values.put(KEY_UID, uid); // Email
values.put(KEY_CREATED_AT, created_at); // Created At
// Inserting Row
db.insert(TABLE_LOGIN, null, values);
db.close(); // Closing database connection
}
/**
* Getting user data from database
* */
public HashMap<String, String> getUserDetails(){
HashMap<String,String> user = new HashMap<String,String>();
String selectQuery = "SELECT * FROM " + TABLE_LOGIN;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// Move to first row
cursor.moveToFirst();
if(cursor.getCount() > 0){
user.put("fname", cursor.getString(1));
user.put("lname", cursor.getString(2));
user.put("email", cursor.getString(3));
user.put("uname", cursor.getString(4));
user.put("uid", cursor.getString(5));
user.put("created_at", cursor.getString(6));
}
cursor.close();
db.close();
// return user
return user;
}
/**
* Getting user login status
* return true if rows are there in table
* */
public int getRowCount() {
String countQuery = "SELECT * FROM " + TABLE_LOGIN;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
int rowCount = cursor.getCount();
db.close();
cursor.close();
// return row count
return rowCount;
}
/**
* Re crate database
* Delete all tables and create them again
* */
public void resetTables(){
SQLiteDatabase db = this.getWritableDatabase();
// Delete All Rows
db.delete(TABLE_LOGIN, null, null);
db.close();
}
公共类DatabaseHandler扩展了SQLiteOpenHelper{
//所有静态变量
//数据库版本
私有静态最终int数据库_VERSION=1;
//数据库名称
私有静态最终字符串数据库\u NAME=“cloud\u contacts”;
//登录表名
私有静态最终字符串表\u LOGIN=“LOGIN”;
//登录表列名称
私有静态最终字符串密钥\u ID=“ID”;
私有静态最终字符串密钥\u FIRSTNAME=“fname”;
私有静态最终字符串密钥\u LASTNAME=“lname”;
私有静态最终字符串密钥\u EMAIL=“EMAIL”;
私有静态最终字符串密钥\u USERNAME=“uname”;
私有静态最终字符串键\u UID=“UID”;
私有静态最终字符串密钥\u CREATED\u AT=“CREATED\u AT”;
公共数据库处理程序(上下文){
super(上下文、数据库名称、null、数据库版本);
}
//创建表
@凌驾
public void onCreate(SQLiteDatabase db){
字符串CREATE\u LOGIN\u TABLE=“CREATE TABLE”+TABLE\u LOGIN+”(“
+密钥ID+“整数主键,”
+键_FIRSTNAME+“文本,”
+键\u LASTNAME+“文本,”
+密钥_电子邮件+“文本唯一,”
+键\用户名+“文本,”
+键UID+“文本,”
+在“+”文本“+”)处创建的按键;
execSQL(创建登录表);
}
//升级数据库
@凌驾
public void onUpgrade(SQLiteDatabase db,int-oldVersion,int-newVersion){
//删除旧表(如果存在)
db.execSQL(“如果存在删除表”+表登录);
//再次创建表
onCreate(db);
}
/**
*在数据库中存储用户详细信息
* */
public void addUser(字符串fname、字符串lname、字符串email、字符串uname、字符串uid、字符串created_at){
SQLiteDatabase db=this.getWritableDatabase();
ContentValues=新的ContentValues();
value.put(KEY_FIRSTNAME,fname);//FIRSTNAME
value.put(KEY_LASTNAME,lname);//LASTNAME
value.put(KEY_EMAIL,EMAIL);//EMAIL
value.put(KEY_USERNAME,uname);//USERNAME
value.put(KEY_UID,UID);//电子邮件
value.put(KEY_CREATED_AT,CREATED_AT);//CREATED AT
//插入行
db.insert(TABLE_LOGIN,null,value);
db.close();//关闭数据库连接
}
/**
*从数据库获取用户数据
* */
公共HashMap getUserDetails(){
HashMap用户=新建HashMap();
String selectQuery=“SELECT*FROM”+表\u登录;
SQLiteDatabase db=this.getReadableDatabase();
Cursor Cursor=db.rawQuery(selectQuery,null);
//移到第一排
cursor.moveToFirst();
if(cursor.getCount()>0){
user.put(“fname”,cursor.getString(1));
user.put(“lname”,cursor.getString(2));
user.put(“email”,cursor.getString(3));
user.put(“uname”,cursor.getString(4));
user.put(“uid”,cursor.getString(5));
user.put(“created_at”,cursor.getString(6));
}
cursor.close();
db.close();
//返回用户
返回用户;
}
/**
*获取用户登录状态
*如果表中有行,则返回true
* */
public int getRowCount(){
字符串计数查询
db.addUser(json_user.getString(KEY_FIRSTNAME),json_user.getString(KEY_LASTNAME),json_user.getString(KEY_EMAIL),json_user.getString(KEY_USERNAME),json_user.getString(KEY_UID),json_user.getString(KEY_CREATED_AT));