http://qiita.com/items/ebd8a56b41711ba459f9

Baseball.groovy

class Baseball {
	def strike = 0, ball = 0, out = 0
	def s = {
		if(2 < ++strike) {
			strike = 0; o()
		}
	}
	def b = {
		if(3 < ++ball) {
			h()
		}
	}
	def o = {
		if(2 < ++out) {
			strike = ball = out = 0
		}
	}
	def f = {
		if(strike < 2) {
			s()
		}
	}
	def h = { strike = ball = 0 }
	def p = { h(); o() }
	def resolve = {
		it.collect {
			this[it](); "$out$strike$ball"
		}.join(",")
	}
}

BaseballTest.groovy

import static org.junit.Assert.*

import org.junit.Test


class BaseballTest {
	@Test
	void test() {
		'''s -> 010
sss -> 010,020,100
bbbb -> 001,002,003,000
ssbbbb -> 010,020,021,022,023,000
hsbhfhbh -> 000,010,011,000,010,000,001,000
psbpfpbp -> 100,110,111,200,210,000,001,100
ppp -> 100,200,000
ffffs -> 010,020,020,020,100
ssspfffs -> 010,020,100,200,210,220,220,000
bbbsfbppp -> 001,002,003,013,023,000,100,200,000
sssbbbbsbhsbppp -> 010,020,100,101,102,103,100,110,111,100,110,111,200,000,100
ssffpffssp -> 010,020,020,020,100,110,120,200,210,000'''.eachLine {
					def (i,o) = it.split(' -> ')
					Baseball target = new Baseball()
					assert target.resolve(i) == o
				}
	}
}