groovy/groovy-core/xdocs/loops.wiki

1 Looping

Groovy supports the usual while {...} and do {...} while loops like Java.

{code:groovy}
x = 0
y = 5

while ( y-- > 0 ) {
    x++
}

assert x == 5

x = 0
y = 5

do {
	x++
} 
while ( --y > 0 )

assert x == 5
{code}

1.1 for loop

The for loop in Groovy is much simpler and works with any kind of array, collection, Map etc.

{code:groovy}
// iterate over a range
x = 0
for ( i in 0..9 ) {
    x += i
}
assert x == 45

// iterate over a list
x = 0
for ( i in [0, 1, 2, 3, 4] ) {
    x += i
}
assert x == 10

// iterate over an array
array = (0..4).toArray()
x = 0
for ( i in array ) {
    x += i
}
assert x == 10

// iterate over the characters in a string
text = "abc"
list = []
for (c in text) {
    list.add(c)
}
assert list == ["a", "b", "c"]
{code}