Is there a way to accept null in resultset - sql-server

Question

I am trying to view data from the SQL Server and I have a column (note) that accept null value because it is not necessary for the user to input any values. I tried using the "rs.wasNull" method as below:
var Note : String = rs.getString("note")
if(rs.wasNull()){
Note = ""
}
But I have still facing the error saying that the "rs.getString("note) cannot be null. Is there any possible ways to return null value?
Below are my whole code:
private fun displayData() {
val sqlCon = SQLCon()
connection = sqlCon.connectionClass()!!
var cUser : String? = intent.getStringExtra("Current User")
if (connection == null) {
Toast.makeText(this, "Failed to make connection", Toast.LENGTH_LONG).show()
} else {
try {
val sql : String=
"SELECT * FROM Goals where Username = '$cUser' "
statement = connection!!.createStatement()
var rs : ResultSet = statement!!.executeQuery(sql)
while (rs.next())
{
var Note : String = rs.getString("note")
if(rs.wasNull()){
Note = ""
}
gList.add(GoalList(rs.getString("gName"), rs.getDouble("tAmount"), rs.getDouble("sAmount"), rs.getString("note"), rs.getString("date")))
}
rs.close()
statement!!.close()
Toast.makeText(this, "Success", Toast.LENGTH_LONG).show()
} catch (e: Exception) { Log.e("Error", e.message!!) }
}
}

Answer 1

You use non-nullable return type for note variable:
var Note : String = rs.getString("note")
First, the variable name should start with a lowercase letter -> note.
Secondly, return value must be nullable
var note : String? = rs.getString("note")
In accordance with JavaDoc getString function:
Returns: the column value; if the value is SQL NULL, the value
returned is null
So no need to check if it was null or not, you can use the following construction to pass default value:
var note : String = rs.getString("note") ?: ""