如何在Android中获取预填充的数据库时解决此错误？

Question

我从从用于SQLite的数据库浏览器创建的填充数据库中获取数据时遇到了一些麻烦，自从我第一次这样做以来，我真的无法理解问题。我遵循的步骤来自这个video，它已经很老了，但是我试了一下，还读了这个article，但是这篇文章基于 kotlin ，我在 java 中工作的问题是我对kotlin一无所知，我只阅读了他的解释，但仍然让我难以理解代码。
以下是我尝试过的代码：

MainActivity：

package com.example.prepolulateddatabase;

import android.database.Cursor;
import android.database.SQLException;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

import java.io.IOException;

public class MainActivity extends AppCompatActivity {

    Cursor c = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        findViewById(R.id.button01).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                DatabaseHelper myDbHelper = new DatabaseHelper(MainActivity.this);
                try {
                    myDbHelper.createDataBase();
                } catch (IOException ioe) {
                    throw new Error("Unable to create database");
                }
                try {
                    myDbHelper.openDataBase();
                } catch (SQLException sqle) {
                    throw sqle;
                }
                Toast.makeText(MainActivity.this, "Successfully Imported", Toast.LENGTH_SHORT).show();

                c = myDbHelper.query("tablename", null, null, null, null, null, null);
                if (c.moveToFirst()) {
                    do {
                        Toast.makeText(MainActivity.this,
                                "_id: " + c.getString(0) + "\n" +
                                        "Name: " + c.getString(1) + "\n" +
                                        "RollNumber: " + c.getString(2) + "\n",
                                Toast.LENGTH_SHORT).show();
                    } while (c.moveToNext());
                }
            }
        });

    }
}

DatabaseHelper

package com.example.prepolulateddatabase;

import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;


public class DatabaseHelper extends SQLiteOpenHelper {

    String DB_PATH = null;
    private static String DB_NAME = "mydatabase";
    private SQLiteDatabase myDataBase;
    private final Context myContext;

    public DatabaseHelper(Context context) {
        super(context, DB_NAME, null, 1);
        this.myContext = context;
        this.DB_PATH = "/data/data/" + context.getPackageName() + "/" + "databases/";
        Log.e("Path 1", DB_PATH);
    }


    public void createDataBase() throws IOException {
        boolean dbExist = checkDataBase();
        if (dbExist) {
        } else {
            this.getReadableDatabase();
            try {
                copyDataBase();
            } catch (IOException e) {
                throw new Error("Error copying database");
            }
        }
    }

    private boolean checkDataBase() {
        SQLiteDatabase checkDB = null;
        try {
            String myPath = DB_PATH + DB_NAME;
            checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
        } catch (SQLiteException e) {
        }
        if (checkDB != null) {
            checkDB.close();
        }
        return checkDB != null ? true : false;
    }

    private void copyDataBase() throws IOException {
        InputStream myInput = myContext.getAssets().open(DB_NAME);
        String outFileName = DB_PATH + DB_NAME;
        OutputStream myOutput = new FileOutputStream(outFileName);
        byte[] buffer = new byte[10];
        int length;
        while ((length = myInput.read(buffer)) > 0) {
            myOutput.write(buffer, 0, length);
        }
        myOutput.flush();
        myOutput.close();
        myInput.close();

    }

    public void openDataBase() throws SQLException {
        String myPath = DB_PATH + DB_NAME;
        myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);

    }

    @Override
    public synchronized void close() {
        if (myDataBase != null)
            myDataBase.close();
        super.close();
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        if (newVersion > oldVersion)
            try {
                copyDataBase();
            } catch (IOException e) {
                e.printStackTrace();
            }
    }

    public Cursor query(String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy) {
        return myDataBase.query("tablename", null, null, null, null, null, null);   
   }
}

调试错误

E/SQLiteLog: (14) cannot open file at line 36667 of [c255889bd9]
    (14) os_unix.c:36667: (2) open(/data/user/0/com.example.prepolulateddatabase/files/com.example.prepolulateddatabase/databases/mydatabase) - 
E/SQLiteDatabase: Failed to open database '/data/user/0/com.example.prepolulateddatabase/files/com.example.prepolulateddatabase/databases/mydatabase'.
    android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14 SQLITE_CANTOPEN): Could not open database
        at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
        at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:211)
        at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:195)
        at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:503)
        at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:204)
        at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:196)
        at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:880)
        at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:865)
        at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:766)
        at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:714)
        at com.example.prepolulateddatabase.DatabaseHelper.checkDataBase(DatabaseHelper.java:49)
        at com.example.prepolulateddatabase.DatabaseHelper.createDataBase(DatabaseHelper.java:33)
        at com.example.prepolulateddatabase.MainActivity$1.onClick(MainActivity.java:29)
        at android.view.View.performClick(View.java:6608)
        at android.view.View.performClickInternal(View.java:6585)
        at android.view.View.access$3100(View.java:782)
        at android.view.View$PerformClick.run(View.java:25945)
        at android.os.Handler.handleCallback(Handler.java:874)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:198)
        at android.app.ActivityThread.main(ActivityThread.java:6729)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.prepolulateddatabase, PID: 11509
    java.lang.Error: Error copying database
        at com.example.prepolulateddatabase.DatabaseHelper.createDataBase(DatabaseHelper.java:40)
        at com.example.prepolulateddatabase.MainActivity$1.onClick(MainActivity.java:29)
        at android.view.View.performClick(View.java:6608)
        at android.view.View.performClickInternal(View.java:6585)
        at android.view.View.access$3100(View.java:782)
        at android.view.View$PerformClick.run(View.java:25945)
        at android.os.Handler.handleCallback(Handler.java:874)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:198)
        at android.app.ActivityThread.main(ActivityThread.java:6729)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

请告诉我是否需要提供有关它的更多信息。如果可能的话，我也需要几天的快速解决方案。
如果此方法无效，则任何其他替代解决方案均有效。
预先感谢你们。快乐编码。