android - 获取 SQLiteCantOpenDatabaseException

Question

在我的应用程序中，我的 Assets 文件夹中有一个 SQLite 数据库的副本。据我所知，它工作正常。当我的应用程序第一次在我的模拟器中安装时，我收到如下错误:

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)

这是我打开数据库的初始代码:

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

这是我尝试过的另一种方法:

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

我也试过用这个:

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

关于如何解决这个问题有什么建议吗？

Answer 1

我总是按照以下步骤从 Assets 文件夹复制我的数据库:

  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();
}

一旦它被复制，我将检查如下:

  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;

}