sqlite数据导入导出

public class ExportImportDB extends Activity {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            super.onCreate(savedInstanceState);
//creating a new folder for the database to be backuped to
            File direct = new File(Environment.getExternalStorageDirectory() + "/Exam Creator");

               if(!direct.exists())
                {
                    if(direct.mkdir()) 
                      {
                       //directory is created;
                      }

                }
            exportDB();
            importDB();

        }
    //importing database
        private void importDB() {
            // TODO Auto-generated method stub

            try {
                File sd = Environment.getExternalStorageDirectory();
                File data  = Environment.getDataDirectory();

                if (sd.canWrite()) {
                    String  currentDBPath= "//data//" + "PackageName"
                            + "//databases//" + "DatabaseName";
                    String backupDBPath  = "/BackupFolder/DatabaseName";
                    File  backupDB= new File(data, currentDBPath);
                    File currentDB  = new File(sd, backupDBPath);

                    FileChannel src = new FileInputStream(currentDB).getChannel();
                    FileChannel dst = new FileOutputStream(backupDB).getChannel();
                    dst.transferFrom(src, 0, src.size());
                    src.close();
                    dst.close();
                    Toast.makeText(getBaseContext(), backupDB.toString(),
                            Toast.LENGTH_LONG).show();

                }
            } catch (Exception e) {

                Toast.makeText(getBaseContext(), e.toString(), Toast.LENGTH_LONG)
                        .show();

            }
        }
    //exporting database 
        private void exportDB() {
            // TODO Auto-generated method stub

            try {
                File sd = Environment.getExternalStorageDirectory();
                File data = Environment.getDataDirectory();

                if (sd.canWrite()) {
                    String  currentDBPath= "//data//" + "PackageName"
                            + "//databases//" + "DatabaseName";
                    String backupDBPath  = "/BackupFolder/DatabaseName";
                    File currentDB = new File(data, currentDBPath);
                    File backupDB = new File(sd, backupDBPath);

                    FileChannel src = new FileInputStream(currentDB).getChannel();
                    FileChannel dst = new FileOutputStream(backupDB).getChannel();
                    dst.transferFrom(src, 0, src.size());
                    src.close();
                    dst.close();
                    Toast.makeText(getBaseContext(), backupDB.toString(),
                            Toast.LENGTH_LONG).show();

                }
            } catch (Exception e) {

                Toast.makeText(getBaseContext(), e.toString(), Toast.LENGTH_LONG)
                        .show();

            }
        }

    }

 <uses-permissionandroid:name="android.permission.WRITE_EXTERNAL_STORAGE">

</uses-permission>