sqlite - Can't import DATABASE into AndroidProject -

i created assets forder in project, after copied database.sql file assets. have sqlitedbhelper.java , can't copy database file /data/data/ .i think can me.

this sqlitedbhelper.java

package com.ngo.evan.testmap;  private final context mycontext;  public sqlitedbhelper(context context) {     super(context, db_name, null, 1);     this.mycontext = context; }  public void createdatabase() throws ioexception{      boolean dbexist = checkdatabase();     if(dbexist){         //do nothing - database exist     }else{         //by calling method , empty database created default system path         //of application gonna able overwrite database our database.         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){         //database does't exist yet.     }      if(checkdb != null){         checkdb.close();     }      return checkdb != null ? true : false; }  private void copydatabase() throws ioexception{      //open local db input stream     inputstream myinput = mycontext.getassets().open(db_name);      // path created empty db     string outfilename = db_path + db_name;      //open empty db output stream     outputstream myoutput = new fileoutputstream(outfilename);      //transfer bytes inputfile outputfile     byte[] buffer = new byte[1024];     int length;     while ((length = myinput.read(buffer))>0){         myoutput.write(buffer, 0, length);     }     //close streams     myoutput.flush();     myoutput.close();     myinput.close(); }  public void opendatabase() throws sqlexception {     //open database     string mypath = db_path + db_name;     mydatabase = sqlitedatabase.opendatabase(mypath, null, sqlitedatabase.open_readonly); }  public synchronized void close() {     if(mydatabase != null)         mydatabase.close();     super.close(); }   @override public void oncreate(sqlitedatabase sqlitedatabase) { }  @override public void onupgrade(sqlitedatabase sqlitedatabase, int i, int i1) { } 

}

how can fix it?