I have created a HashMap called instantHashMap and loaded it with data from
a query .

I can load a variable with an explicit value for the HashMap key and
successfully output the HashMap value:

<c:set var = "gameno" value="2" />
<c:out value = "${instantHashMap[gameno]}" />

But when I load my variable value from my data like this...

<c:set var = "gameno" value="${rvo.gameNo}" />
<c:out value = "${instantHashMap[gameno]}" />

...it doesn't work.

My loaded variable value is correct because this statement does work and
reflects the data obtained from my query:

<c:out value = "${gameno}" />

I have determined that the hashmap key must be a string because if I change
the original statement

<c:set var = "gameno" value="2" />

to

<c:set var = "gameno" value="${ 1 + 1 }" />

this statement

<c:out value = "${gameno}" />

prints a 2, but the statatement

<c:out value = "${instantHashMap[gameno]}" />

now fails.

The database data type of my gameno field is varchar, so Java should see it
as a string.

What am I doing wrong?