def map = [a:3, b:2, c:1]
map = map.sort {it.value}
assert map == 1

Turns out doing a reverse sort on a Map by values is almost as easy.

def map = [a:1, b:2, c:3]
map = map.sort {a, b -> b.value <=> a.value}
assert map == 1

Using the spaceship operator (‘< =>‘) you can define a very terse syntax for accessing ‘compareTo’, as long as the values in the map implement Comparable that is.
Nice!

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