sqlite-SQLite不能打開數據庫的異常

SQLite不能打開數據庫的異常

在程序的中我從assets中復制了SQLite數據庫，可以使用。當把程序第一次安裝在仿真器中運行時，獲得以下錯誤。

Failed to open the database. closing it.

android.database.sqlite.SQLiteCantOpenDatabaseException: unable to open database file

E/SQLiteDatabase(7516): at android.database.sqlite.SQLiteDatabase.dbopen(Native Method)
E/SQLiteDatabase(29308):    at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:1013)

E/SQLiteDatabase(29308):    at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:986)



E/SQLiteDatabase(29308):    at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:962)

E/SQLiteDatabase(29308):    at com.guayama.database.URLDatabaseHelper.checkDBExists(URLDatabaseHelper.java:86)

 E/SQLiteDatabase(29308):   at com.guayama.database.URLDatabaseHelper.createURLDB(URLDatabaseHelper.java:54)

 E/SQLiteDatabase(29308):   at com.guayama.database.URLDatabaseHelper.<init>(URLDatabaseHelper.java:38)

打開數據庫用的代碼：

SQLiteDatabase.openDatabase(mPath, null,SQLiteDatabase.CREATE_IF_NECESSARY);

也試過以下的代碼打開：

checkDB = SQLiteDatabase.openDatabase(mPath, null,
                SQLiteDatabase.OPEN_READONLY);

還有這個代碼片段：

 SQLiteDatabase.openDatabase(mPath, null,SQLiteDatabase.NO_LOCALIZED_COLLATORS);

可以幫我看下問題所在嗎？謝謝！

最佳回答：

我經常用下面的步驟從assets文件夾中復制數據庫

private void copyDatabase() throws IOException{

        InputStream inputStream = context.getAssets().open(DB_NAME);
        String dbCreatePath = DB_PATH+DB_NAME;
        OutputStream outputStream = new FileOutputStream(dbCreatePath);
        byte[] buffer = new byte[1024];
        int length;
        while((length = inputStream.read(buffer))>0){
            outputStream.write(buffer,0,length);
        }
        outputStream.flush();
        outputStream.close();
        inputStream.close();
}

然後我會用下面的方法檢查一遍：

private boolean checkDatabase(){
    SQLiteDatabase checkDB = null;
    try {
        String dbPath = DB_PATH+DB_NAME;
        checkDB = SQLiteDatabase.openDatabase(dbPath, null,     
            SQLiteDatabase.OPEN_READWRITE);
    } catch (SQLiteException e) {
        // TODO: handle exception
    }
    if(checkDB!=null){
        checkDB.close();}
    return checkDB != null ? true:false;

}