Checking to see if the password matches the particular user- PostgreSQL and Java

I am trying to implement a section of code which checks that the hashed_password and user_name match. The code below first checks to see if the username is valid, then if valid the code will then check to see if the password matches the username. However, that is section of the code that is not working. I can enter the correct username from the database and the corresponding correct password from the database and it displays the correct message You can proceed!. But if I enter the correct username from the database but an incorrect password it still displays You can proceed!. Any help is appreciated!

public void letsLogin() throws SQLException
 {

  System.out.print("Enter your user name: ");
  username = in.next();


  sql = "SELECT " + "username " + "FROM" + " users_table" + " where username = "
        + "'" + username + "'";


  result = s.executeQuery(sql);

 // select hashed_password
  sql_hash = "SELECT " + "hashed_password = " + "crypt(" + "'"
                 + hashed_password + "'" + ","+ "hashed_password)" +
                 " as matched " + "from users" +  " where username = "
                 + "'" + username + "'";

 result2 = s2.executeQuery(sql_hash);

  if(result.next())
  {
        System.out.println("You are registered!");
         // ask user to enter password

        System.out.println("Enter your password: ");
        hashed_password = stdin2.next();

        // check to see if username and hashed_password match
        if(result2.next())
        {
           System.out.println("You can proceed!");
        }

        else
        {
           System.exit(0);
        }


  }