Android SQLiteLog:（14）无法打开文件
我正在设计我的第一个应用程序，我遇到以下错误： 运行应用程序时出错：Android SQLiteLog:（14）无法打开文件,android,Android,我正在设计我的第一个应用程序，我遇到以下错误： 运行应用程序时出错： 03-10 05:21:14.767 15427-15427/com.example.pratik.walkmeter E/SQLiteLog: (14) cannot open file at line 32456 of [bda77dda96] 03-10 05:21:14.767 15427-15427/com.example.pratik.walkmeter E/SQLiteLog: (14) os_unix.c:32
03-10 05:21:14.767 15427-15427/com.example.pratik.walkmeter E/SQLiteLog: (14) cannot open file at line 32456 of [bda77dda96]
03-10 05:21:14.767 15427-15427/com.example.pratik.walkmeter E/SQLiteLog: (14) os_unix.c:32456: (13) open(/data/user/0/com.example.pratik.walkmeter/databases/newuserdataDB.db) -
03-10 05:21:14.767 15427-15427/com.example.pratik.walkmeter E/SQLiteDatabase: Failed to open database '/data/user/0/com.example.pratik.walkmeter/databases/newuserdataDB.db'. android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:209)
at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:808)
at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:793)
at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:696)
at android.app.ContextImpl.openOrCreateDatabase(ContextImpl.java:652)
at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:289)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:223)
at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:163)
at com.example.pratik.walkmeter.DBHelper.databaseToString(DBHelper.java:54)
at com.example.pratik.walkmeter.NewUserInformation.printDatabase(NewUserInformation.java:55)
at com.example.pratik.walkmeter.NewUserInformation.onCreate(NewUserInformation.java:51)
at android.app.Activity.performCreate(Activity.java:6679)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
03-10 05:21:14.768 15427-15427/com.example.pratik.walkmeter D/AndroidRuntime: Shutting down VM
03-10 05:21:14.768 15427-15427/com.example.pratik.walkmeter E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.pratik.walkmeter, PID: 15427
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.pratik.walkmeter/com.example.pratik.walkmeter.NewUserInformation}: android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Caused by: android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:209)
at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:808)
at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:793)
at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:696)
at android.app.ContextImpl.openOrCreateDatabase(ContextImpl.java:652)
at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:289)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:223)
at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:163)
at com.example.pratik.walkmeter.DBHelper.databaseToString(DBHelper.java:54)
at com.example.pratik.walkmeter.NewUserInformation.printDatabase(NewUserInformation.java:55)
at com.example.pratik.walkmeter.NewUserInformation.onCreate(NewUserInformation.java:51)
at android.app.Activity.performCreate(Activity.java:6679)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DBHelper extends SQLiteOpenHelper{
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME="newuserdataDB.db";
public static final String TABLE_NAME = "newusertable";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_NAME= "name";
private static String DB_PATH = "";
public DBHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
String query = "CREATE TABLE " + TABLE_NAME + "(" +
COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
COLUMN_NAME + " TEXT " +
");";
db.execSQL(query);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
public void addProduct(NewUserData product){
ContentValues values = new ContentValues();
values.put(COLUMN_NAME, product.get_newusernamedata());
SQLiteDatabase db = getWritableDatabase();
db.insert(TABLE_NAME, null, values);
db.close();
}
public String databaseToString(){
String dbString = "";
SQLiteDatabase db = getWritableDatabase();
String query = "SELECT * FROM " + TABLE_NAME + " WHERE 1";// why not leave out the WHERE clause?
//Cursor points to a location in your results
Cursor recordSet = db.rawQuery(query, null);
//Move to the first row in your results
recordSet.moveToFirst();
//Position after the last row means the end of the results
while (!recordSet.isAfterLast()) {
// null could happen if we used our empty constructor
if (recordSet.getString(recordSet.getColumnIndex("name")) != null) {
dbString += recordSet.getString(recordSet.getColumnIndex("name"));
dbString += "\n";
}
recordSet.moveToNext();
}
db.close();
return dbString;
}
}
package com.example.pratik.walkmeter;
public class NewUserData {
private int _id;
private String _newusernamedata;
public NewUserData(){}
public NewUserData(String newusernamedata) {
this._newusernamedata = newusernamedata;
}
public int get_id() {
return _id;
}
public void set_id(int _id) {
this._id = _id;
}
public String get_newusernamedata() {
return _newusernamedata;
}
public void set_newusernamedata(String _newusernamedata) {
this._newusernamedata = _newusernamedata;
}
}
public class NewUserInformation extends AppCompatActivity {
EditText NewUserName, NewUserAge;
RadioGroup NewUserSex;
TextView dataoutput;
String sexlabel;
DBHelper dbHandler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_new_user_information);
//intialize the fields
NewUserName = (EditText) findViewById(R.id.NewUserName);
NewUserAge = (EditText) findViewById(R.id.NewUserAge);
NewUserSex = (RadioGroup) findViewById(R.id.NewUserSex);
dataoutput = (TextView) findViewById(R.id.dataoutput);
//Sex Group Selector
NewUserSex.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener(){
@Override
public void onCheckedChanged(RadioGroup group, @IdRes int checkedId) {
RadioButton rb = (RadioButton) group.findViewById(checkedId);
switch (rb.getId()){
case R.id.Male:
sexlabel = "M";
break;
case R.id.Female:
sexlabel = "F";
break;
}
}
});
//Intialize Database
dbHandler = new DBHelper(this, null, null, 1);
printDatabase();
}
public void printDatabase(){
String dbString = dbHandler.databaseToString();
dataoutput.setText(dbString);
NewUserName.setText("");
}
public void addButtonClicked(View view){
// dbHandler.add needs an object parameter.
NewUserData product = new NewUserData(NewUserName.getText().toString());
dbHandler.addProduct(product);
printDatabase();
}
}
获取可写数据库时
getWritableDatabase（）thisthis.getWritableDatabase（）同样适用于getReadableDatabase（）
类似的这个.getReadableDatabase
，因为在编写数据库之前，您没有打开它。
将此方法添加到DBHelper
类
// check the state of db ??....
public boolean isOpen() {
return database != null && database.isOpen();
}
@Override
public synchronized void close() {
if (database!= null)
database.close();
super.close();
}
现在，您的addProduct
方法将是-
public void addProduct(NewUserData product) {
if (!isOpen()) openDataBase();
SQLiteDatabase database = this.getWritableDatabase();
// perform your operations here...
// call close to close the db after writing it.
}
Tadaaa…似乎您没有将数据库复制到该位置。错误似乎是db文件不可用。请尝试以下代码：
public class DatabaseHelper extends SQLiteOpenHelper {
class DB {
public static Uri URI;
public static int VERSION = 1;
public static final String NAME = "yourdatabase.db";
public static String PATH = "";
}
//region Variable Declarations
// The Android's default system path of your application database.
public static SQLiteDatabase myDataBase;
private final Context myContext;
//endregion
//region Private Methods
/**
* Constructor Takes and keeps a reference of the passed context in order to
* access to the application assets and resources.
*/
public DatabaseHelper(Context context) {
super(context, DB.NAME, null, 1);
this.myContext = context;
DB.PATH = myContext.getDatabasePath(DB.NAME).getPath();
DB.URI = Uri.fromFile(myContext.getDatabasePath(DB.NAME));
// try {
// openDataBase();
// } catch (SQLException e) {
// // TODO Auto-generated catch block
// Utils.PrintStackTrace(e);
// } catch (IOException e) {
// // TODO Auto-generated catch block
// Utils.PrintStackTrace(e);
// }
}
/**
* *****************************************
* Creates a empty database on the system
* and rewrites it with your own database.
* ******************************************
*/
public void createDataBase() throws IOException {
boolean dbExist = checkDataBase();
if (!dbExist) {
// By calling this method and empty database will be created into
// the default system path
// of your application so we are gonna be able to overwrite that
// database with our database.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
/**
* *******************************************
* Check if the database already exist to avoid
* re-copying the file each
* time you open the application.
*
* @return true if it exists, false if it doesn't
* *******************************************
*/
private boolean checkDataBase() {
SQLiteDatabase checkDB = null;
try {
String myPath = DB.PATH;
checkDB = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.OPEN_READONLY
| SQLiteDatabase.NO_LOCALIZED_COLLATORS);
/*int DB_EXIST_VERSION = PreferenceManager
.getDefaultSharedPreferences(myContext).getInt(
"DB_VERSION", 0);
if (DB.VERSION != DB_EXIST_VERSION) {
checkDB = null;
}*/
} catch (SQLiteException e) {
Utils.PrintStackTrace(e);
} catch (Exception e1) {
Utils.PrintStackTrace(e1);
}
if (checkDB != null) {
checkDB.close();
}
return checkDB != null;
}
/**
* *******************************************
* Copies your database from your local
* assets-folder to the just created empty
* database in the system folder, from
* where it can be accessed and handled.
* This is done by transferring bytestream.
* *******************************************
*/
private void copyDataBase() throws IOException {
// Open your local db as the input stream
InputStream myInput = myContext.getAssets().open(DB.NAME);
// Path to the just created empty db
String outFileName = DB.PATH;
// Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
// transfer bytes from the input file to the output file
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0) {
myOutput.write(buffer, 0, length);
}
// Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
PreferenceManager.getDefaultSharedPreferences(myContext).edit()
.putInt("DB_VERSION", DB.VERSION).commit();
}
/**
* *****************************************
* Method to open the database
* ******************************************
*/
public void openDataBase() throws SQLException, IOException {
createDataBase();
// Open the database
String myPath = DB.PATH;
myDataBase = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.NO_LOCALIZED_COLLATORS);
}
/**
* *****************************************
* Method to close database
* ******************************************
*/
@Override
public synchronized void close() {
try {
if (myDataBase != null)
myDataBase.close();
myDataBase = null;
super.close();
} catch (Exception e) {
// TODO Auto-generated catch block
Utils.PrintStackTrace(e);
}
}
/**
* *****************************************
* Method onCreate
* ******************************************
*/
@Override
public void onCreate(SQLiteDatabase db) {
}
/**
* *****************************************
* Method onUpgrade
* ******************************************
*/
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
//endregion
}