Sorting a Map by value with Groovy is very simple, due to the added ‘sort’ method on the Map interface.
[groovy language=”language="true”]
def map = [a:3, b:2, c:1]
map = map.sort {it.value}
assert map == [c:1, b:2, a:3]
[/groovy]
Turns out doing a reverse sort on a Map by values is almost as easy.
[groovy language=”language="true”]
def map = [a:1, b:2, c:3]
map = map.sort {a, b -> b.value <=> a.value}
assert map == [c:3, b:2, a:1]
[/groovy]
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!
