Can you do something like this in a velocity template?
#set ($map = $myobject.getMap() )
#foreach ($mapEntry in $map.entrySet())
$mapEntry.key()&
Your mistake is referring to key and value as methods (with trailing "()" parenthesis) instead of as properties. Try this:
#set ($map = $myobject.getMap() )
#foreach ($mapEntry in $map.entrySet())
$mapEntry.key
$mapEntry.value
#end
In other words, use either a property, like mapEntry.key, or the method, like mapEntry.getKey().