when i tried to invoke thread.start() it is not working first time

i created this function and i want to use multthreading.

public String selectQuery(final String qry) {

        new Thread(new Runnable() {
            public void run() {
                statement = creatStatement();
                try {
                    resultSet = statement.executeQuery(qry);
                    while (resultSet.next()) {
                        fullName = resultSet.getString(1);
                } catch (SQLException e) {


    return fullName;

   // return null;

i invoked this function in button OnClick event but when i called the first time it doesn’t display anything because the run method not executed after start thread but the second time it works.

i used debug mode to watch what is going i searched the solution but i didn’t get the best solution.

So what is wrong in my code, i need help