Update async2 example

Author: devlights

examples/basic/helloworld/async2.go

@@ -0,0 +1,38 @@
+package async2
+
+import (
+	"log"
+	"math/rand"
+	"sync"
+	"time"
+)
+
+// Async2 -- HelloWorld 非同期版 (2)
+func Async2() error {
+	log.SetFlags(0)
+
+	var (
+		wg    = new(sync.WaitGroup)
+		ch    = make(chan string)
+		delay = func() time.Duration {
+			return time.Duration(rand.Intn(200)) * time.Millisecond
+		}
+	)
+
+	var (
+		hello   = newRunner("hello", wg, ch, delay)
+		world   = newRunner("world", wg, ch, delay)
+		closer  = newCloser(wg, ch)
+		printer = newPrinter(ch)
+	)
+
+	wg.Add(2)
+
+	go hello.run()
+	go world.run()
+	go closer.run()
+
+	printer.run()
+
+	return nil
+}

examples/basic/helloworld/async2/async2.go

@@ -0,0 +1,22 @@
+package async2
+
+import "sync"
+
+type _closer struct {
+	wg *sync.WaitGroup
+	ch chan<- string
+}
+
+func newCloser(wg *sync.WaitGroup, ch chan<- string) *_closer {
+	c := new(_closer)
+
+	c.wg = wg
+	c.ch = ch
+
+	return c
+}
+
+func (me *_closer) run() {
+	defer close(me.ch)
+	me.wg.Wait()
+}

examples/basic/helloworld/async2/closer.go

@@ -0,0 +1,19 @@
+package async2
+
+import "log"
+
+type _printer struct {
+	ch <-chan string
+}
+
+func newPrinter(ch <-chan string) *_printer {
+	p := new(_printer)
+	p.ch = ch
+	return p
+}
+
+func (me *_printer) run() {
+	for v := range me.ch {
+		log.Println(v)
+	}
+}

examples/basic/helloworld/async2/printer.go

@@ -0,0 +1,42 @@
+package async2
+
+import (
+	"fmt"
+	"sync"
+	"time"
+)
+
+const (
+	LoopCount = 20
+)
+
+type _runner struct {
+	name  string
+	wg    *sync.WaitGroup
+	ch    chan<- string
+	delay func() time.Duration
+}
+
+func newRunner(name string, wg *sync.WaitGroup, ch chan<- string, delay func() time.Duration) *_runner {
+	r := new(_runner)
+
+	r.name = name
+	r.wg = wg
+	r.ch = ch
+	r.delay = delay
+
+	return r
+}
+
+func (me *_runner) String() string {
+	return me.name
+}
+
+func (me *_runner) run() {
+	defer me.wg.Done()
+	for i := 0; i < LoopCount; i++ {
+		d := me.delay()
+		time.Sleep(d)
+		me.ch <- fmt.Sprintf("%d:%s (%v)", i, me, d)
+	}
+}

examples/basic/helloworld/async2/runner.go

@@ -1,6 +1,9 @@
 package helloworld
 
-import "github.com/devlights/try-golang/mapping"
+import (
+	"github.com/devlights/try-golang/examples/basic/helloworld/async2"
+	"github.com/devlights/try-golang/mapping"
+)
 
 type (
 	register struct{}
@@ -15,6 +18,6 @@ func NewRegister() mapping.Register {
 func (r *register) Regist(m mapping.ExampleMapping) {
 	m["helloworld_sync"] = Sync
 	m["helloworld_async"] = Async
-	m["helloworld_async2"] = Async2
+	m["helloworld_async2"] = async2.Async2
 	m["helloworld_mixed"] = Mixed
 }