more interesting demos

This commit is contained in:
Fabian Jakobs 2012-03-21 12:56:31 +01:00
commit 0ff2e3540a
2 changed files with 99 additions and 27 deletions

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@ -1,26 +1,41 @@
//http://groovy.codehaus.org/Concurrency+with+Groovy
import java.util.concurrent.atomic.AtomicInteger
//http://groovy.codehaus.org/Martin+Fowler%27s+closure+examples+in+Groovy
def counter = new AtomicInteger()
synchronized out(message) {
println(message)
class Employee {
def name, salary
boolean manager
String toString() { return name }
}
def th = Thread.start {
for( i in 1..8 ) {
sleep 30
out "thread loop $i"
counter.incrementAndGet()
}
def emps = [new Employee(name:'Guillaume', manager:true, salary:200),
new Employee(name:'Graeme', manager:true, salary:200),
new Employee(name:'Dierk', manager:false, salary:151),
new Employee(name:'Bernd', manager:false, salary:50)]
def managers(emps) {
emps.findAll { e -> e.isManager() }
}
for( j in 1..4 ) {
sleep 50
out "main loop $j"
counter.incrementAndGet()
assert emps[0..1] == managers(emps) // [Guillaume, Graeme]
def highPaid(emps) {
threshold = 150
emps.findAll { e -> e.salary > threshold }
}
th.join()
assert emps[0..2] == highPaid(emps) // [Guillaume, Graeme, Dierk]
assert counter.get() == 12
def paidMore(amount) {
{ e -> e.salary > amount}
}
def highPaid = paidMore(150)
assert highPaid(emps[0]) // true
assert emps[0..2] == emps.findAll(highPaid)
def filename = 'test.txt'
new File(filename).withReader{ reader -> doSomethingWith(reader) }
def readersText
def doSomethingWith(reader) { readersText = reader.text }
assert new File(filename).text == readersText

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//http://www.scala-lang.org/node/227
/* Defines a new method 'sort' for array objects */
object implicits extends Application {
implicit def arrayWrapper[A : ClassManifest](x: Array[A]) =
new {
def sort(p: (A, A) => Boolean) = {
util.Sorting.stableSort(x, p); x
// http://www.scala-lang.org/node/54
package examples.actors
import scala.actors.Actor
import scala.actors.Actor._
abstract class PingMessage
case object Start extends PingMessage
case object SendPing extends PingMessage
case object Pong extends PingMessage
abstract class PongMessage
case object Ping extends PongMessage
case object Stop extends PongMessage
object pingpong extends Application {
val pong = new Pong
val ping = new Ping(100000, pong)
ping.start
pong.start
ping ! Start
}
class Ping(count: Int, pong: Actor) extends Actor {
def act() {
println("Ping: Initializing with count "+count+": "+pong)
var pingsLeft = count
loop {
react {
case Start =>
println("Ping: starting.")
pong ! Ping
pingsLeft = pingsLeft - 1
case SendPing =>
pong ! Ping
pingsLeft = pingsLeft - 1
case Pong =>
if (pingsLeft % 1000 == 0)
println("Ping: pong from: "+sender)
if (pingsLeft > 0)
self ! SendPing
else {
println("Ping: Stop.")
pong ! Stop
exit('stop)
}
}
}
val x = Array(2, 3, 1, 4)
println("x = "+ x.sort((x: Int, y: Int) => x < y))
}
}
class Pong extends Actor {
def act() {
var pongCount = 0
loop {
react {
case Ping =>
if (pongCount % 1000 == 0)
println("Pong: ping "+pongCount+" from "+sender)
sender ! Pong
pongCount = pongCount + 1
case Stop =>
println("Pong: Stop.")
exit('stop)
}
}
}
}