Tengo un problema al cerrar una conexión a MySQL.

Me sale el error:

java.sql.SQLException: operación no permitida después de ResultSet cerrado

Mi código:

public static ResultSet sqlquery (String query)
{
 ResultSet rs=null;
 Connection connection=null;
 Statement st=null;
 try{   
     Class.forName("com.mysql.jdbc.Driver");
     connection = DriverManager.getConnection("databaseadress","username","password");
     st = connection.createStatement();  
     rs = st.executeQuery(query);

    }catch(SQLException e){System.out.println("SQL error: " + e);}
      catch(Exception e){System.out.println("Error: " + e);}
       finally {
       try{
          if(rs != null) rs.close();
          if(st!= null) st.close();
          if(connection != null)  connection.close();
  }catch(SQLException e){System.out.println("SQL error : " + e);}

    }
     return rs;
}