visitor demo

Author: kimi0230

Visitor/demo.go

@@ -0,0 +1,102 @@
+package visitor
+
+import "fmt"
+
+type Action interface {
+	GetManConclusion(Man)
+	GetWomanConclusion(Woman)
+}
+
+type Success struct {
+	Name string
+}
+
+func (s *Success) GetManConclusion(m Man) {
+	if s == nil {
+		return
+	}
+	fmt.Printf("%s %s 時, 背後多半有一個偉大的女人 \n", m.Name, s.Name)
+}
+
+func (s *Success) GetWomanConclusion(w Woman) {
+	if s == nil {
+		return
+	}
+	fmt.Printf("%s %s 時, 背後多半有一個不成功的男人 \n", w.Name, s.Name)
+}
+
+type Failing struct {
+	Name string
+}
+
+func (s *Failing) GetManConclusion(m Man) {
+	if s == nil {
+		return
+	}
+	fmt.Printf("%s %s 時, 悶頭喝酒, 誰也不用勸 \n", m.Name, s.Name)
+}
+
+func (s *Failing) GetWomanConclusion(w Woman) {
+	if s == nil {
+		return
+	}
+	fmt.Printf("%s %s 時, 眼淚汪汪, 誰也勸不了 \n", w.Name, s.Name)
+}
+
+type Person interface {
+	Accept(Action)
+}
+
+type Man struct {
+	Name string
+}
+
+func (m *Man) Accept(visitor Action) {
+	if m == nil {
+		return
+	}
+	visitor.GetManConclusion(*m)
+}
+
+type Woman struct {
+	Name string
+}
+
+func (w *Woman) Accept(visitor Action) {
+	if w == nil {
+		return
+	}
+	visitor.GetWomanConclusion(*w)
+}
+
+type ObjectStructurePerson struct {
+	elemetes []Person
+}
+
+func (o *ObjectStructurePerson) Attach(ele Person) {
+	if o == nil || ele == nil {
+		return
+	}
+	o.elemetes = append(o.elemetes, ele)
+}
+
+func (o *ObjectStructurePerson) Detach(ele Person) {
+	if o == nil || ele == nil {
+		return
+	}
+	for i, val := range o.elemetes {
+		if val == ele {
+			o.elemetes = append(o.elemetes[:i], o.elemetes[i+1:]...)
+			break
+		}
+	}
+}
+
+func (o *ObjectStructurePerson) Accept(v Action) {
+	if o == nil {
+		return
+	}
+	for _, val := range o.elemetes {
+		val.Accept(v)
+	}
+}

Visitor/dmeo_test.go

@@ -0,0 +1,16 @@
+package visitor
+
+import "testing"
+
+func TestDemo(t *testing.T) {
+	o := new(ObjectStructurePerson)
+	o.Attach(&Man{"男人"})
+	o.Attach(&Woman{"女人"})
+
+	// 成功
+	conreteVA := &Success{"成功"}
+	// 失敗
+	conreteVB := &Failing{"失敗"}
+	o.Accept(conreteVA)
+	o.Accept(conreteVB)
+}