try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        String url = "jdbc:sqlserver://P5-GKTKX52//SQLARA:1433;databaseName=DBNAME";
        Connection conn = DriverManager.getConnection(url,"username","pass");

Cannot open database  requested by the login. The login failed.

1. String url = "jdbc:sqlserver://P5-GKTKX52\SQLARA:1433;databaseName=ARA;user=username;password=pass"

2. Connection conn = DriverManager.getConnection("jdbc:jtds:sqlserver://P5-GKTKX52:1433;instance=SQLARA;DatabaseName=DB","Login","pass");