如何在Android的SQLite数据库中实现Sql密码

Question

我首先在sqlite数据库浏览器上创建一个数据库，然后在数据库浏览器>文件>设置加密中设置密码。现在如何在Android上解密。当我编写此代码时显示错误。我在这一行出现错误：

mDataBase = SQLiteDatabase.openDatabase(dbPath, "123", null, SQLiteDatabase.NO_LOCALIZED_COLLATORS);

错误表明：原因：net.sqlcipher.database.SQLiteException：文件不是数据库：，正在编译：从sqlite_master中选择count（*）；谁能告诉我怎么了？

---

import android.content.Context;
import android.database.SQLException;
//import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import net.sqlcipher.database.SQLiteDatabase;
import net.sqlcipher.database.SQLiteDatabase;
import net.sqlcipher.database.SQLiteOpenHelper;
import net.sqlcipher.database.SQLiteDatabase.CursorFactory;


import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.File;
import net.sqlcipher.database.SQLiteDatabase;
import android.app.Activity;
import android.os.Bundle;

public class DatabaseHelper extends SQLiteOpenHelper {

    private static String TAG = DatabaseHelper.class.getName();
    private static String DB_PATH = "";
    private static String DB_NAME = "ecash.db";// Database name
    private SQLiteDatabase mDataBase;
    private final Context mContext;
    File databaseFile=null;
    public DatabaseHelper(Context context) {
        super(context, DB_NAME, null, 1);
        DB_PATH = context.getApplicationInfo().dataDir + "/databases/";
        this.mContext = context;
        SQLiteDatabase.loadLibs(context);
        File databaseFile = context.getDatabasePath(DB_NAME);
        databaseFile.mkdirs();
    }

    public void createDataBase() throws IOException {
        // If database not exists copy it from the assets
        boolean mDataBaseExist = checkDataBase();
        if (!mDataBaseExist) {
            this.getWritableDatabase("123");
            this.close();
            try {
                // Copy the database from assests
                copyDataBase();
                Log.e(TAG, "createDatabase database created");
            } catch (IOException mIOException) {
                throw new Error(mIOException.toString() + " : " + DB_PATH
                        + DB_NAME);// "ErrorCopyingDataBase"
            }
        }
    }

    private boolean checkDataBase() {
        File dbFile = new File(DB_PATH + DB_NAME);
        return dbFile.exists();
    }

    // Copy the database from assets
    private void copyDataBase() throws IOException {
        InputStream mInput = mContext.getAssets().open(DB_NAME);
        String outFileName = DB_PATH + DB_NAME;
        OutputStream mOutput = new FileOutputStream(outFileName);
        byte[] mBuffer = new byte[4096];
        int mLength;
        while ((mLength = mInput.read(mBuffer)) > 0) {
            mOutput.write(mBuffer, 0, mLength);
        }
        mOutput.flush();
        mOutput.close();
        mInput.close();
    }

    // Open the database, so we can query it
    public boolean openDataBase() throws SQLException {
        String mPath = DB_PATH + DB_NAME;
        //File dbFile = new File(DB_PATH + DB_NAME);
        //File databaseFile = mContext.getDatabasePath(DB_NAME);
        //databaseFile.mkdirs();
        //databaseFile.delete();

        SQLiteDatabase.loadLibs(mContext);

        String dbPath = mContext.getDatabasePath("ecash.db").getPath();


        //databaseFile.delete();
        SQLiteDatabase.loadLibs(mContext);
          //mDataBase = SQLiteDatabase.openOrCreateDatabase(databaseFile, "123456Sa", null);
        //mDataBase = SQLiteDatabase.openDatabase(mPath, "123456Sa",null, SQLiteDatabase.NO_LOCALIZED_COLLATORS);
        mDataBase = SQLiteDatabase.openDatabase(dbPath, "123", null, SQLiteDatabase.NO_LOCALIZED_COLLATORS);

        return mDataBase != null;
    }

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

    @Override
    public void onCreate(SQLiteDatabase db) {

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }


}

在我编写此代码时显示错误。我在这一行出现错误：

mDataBase = SQLiteDatabase.openDatabase(dbPath, "123", null, SQLiteDatabase.NO_LOCALIZED_COLLATORS);

错误表明：原因：net.sqlcipher.database.SQLiteException：文件不是数据库：，正在编译：从sqlite_master中选择count（*）； 怎么了 ？以及我该如何在android部分解密密码???