I have a Map in EL as ${map} and I am trying to get the value of it using a key which is by itself also an EL variable ${key} with the
$ is not the start of a variable name, it indicates the start of an expression. You should use ${map[key]} to access the property key in map map.
You can try it on a page with a GET parameter, using the following query string for example ?whatEver=something
whatEver:
This will output:
whatEver: something
See: https://stackoverflow.com/tags/el/info and scroll to the section "Brace notation".