feat: init

Author: chenlumin

go.work

@@ -0,0 +1,3 @@
+go 1.18
+
+use ./go

go/creational/prototype/prototype.go

@@ -0,0 +1,3 @@
+package prototype
+
+

go/go.mod

@@ -0,0 +1,3 @@
+module github.com/Miltian/design-pattern
+
+go 1.18

go/structural/REAME.md

@@ -0,0 +1,4 @@
+### 发布订阅者
+
+1. 一对多
+2. 当一个对象改变, 其他依赖的对象会被同步通知

go/structural/observer/event_bus.go

@@ -0,0 +1,76 @@
+package observer
+
+import (
+	"fmt"
+	"reflect"
+	"sync"
+)
+
+type IEventBus interface {
+	// on(eventName string, handler interface{})
+	// off(evnetName string, handler interface{})
+	// 订阅事件
+	Subscribe(eventName string, handler interface{}) error
+	// 取消订阅事件
+	UnSubscribe(eventName string, handler interface{}) error
+	// 发布事件
+	Publish(eventName string, args ...interface{})
+}
+
+type AsyncEventBus struct {
+	handlers map[string][]reflect.Value
+	lock     sync.Mutex
+}
+
+func NewAsyncEventBus() *AsyncEventBus {
+	return &AsyncEventBus{
+		handlers: make(map[string][]reflect.Value),
+		lock:     sync.Mutex{},
+	}
+}
+
+func (b *AsyncEventBus) Subscribe(eventName string, handler interface{}) error {
+
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	v := reflect.ValueOf(handler)
+	if v.Type().Kind() != reflect.Func {
+		return fmt.Errorf("handler must be Func but is %s", v.Type().Kind())
+	}
+
+	// 往事件注册函数, 不存在初始化数组
+	handlers, ok := b.handlers[eventName]
+	if !ok {
+		handlers = []reflect.Value{}
+	}
+	handlers = append(handlers, v)
+	b.handlers[eventName] = handlers
+	return nil
+}
+
+func (b *AsyncEventBus) UnSubscribe(eventName string, handler interface{}) error {
+	return nil
+}
+
+// 发布事件
+func (b *AsyncEventBus) Publish(eventName string, args ...interface{}) {
+	handlers, ok := b.handlers[eventName]
+	if !ok {
+		return
+	}
+
+	params := make([]reflect.Value, len(args))
+	for _, v := range args {
+		arg := reflect.ValueOf(v)
+		params = append(params, arg)
+	}
+
+	// 	// handler := reflect.ValueOf(v)
+	// 	go v.Call(params)
+	// }
+
+	for i := range handlers {
+		go handlers[i].Call(params)
+	}
+}

go/structural/observer/observer.go

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+package observer
+
+import "fmt"
+
+type ISubject interface {
+	Register(observer IObserver)
+	Remove(observer IObserver)
+	Notify(msg string)
+}
+
+type IObserver interface {
+	Update(msg string)
+}
+
+//发布者
+type Subject struct {
+	observers []IObserver
+}
+
+// 新增订阅者
+func (s *Subject) Register(observer IObserver) {
+	s.observers = append(s.observers, observer)
+}
+
+// 移除订阅者
+func (s *Subject) Remove(observer IObserver) {
+	for i, v := range s.observers {
+		if v == observer {
+			s.observers = append(s.observers[:i], s.observers[i:]...)
+		}
+	}
+}
+
+func (s *Subject) Notify(msg string) {
+	for _, v := range s.observers {
+		v.Update(msg)
+	}
+}
+
+// 订阅者
+type Observer1 struct{}
+
+func (o *Observer1) Update(msg string) {
+	fmt.Printf("%s observer1 update! \n", msg)
+}
+
+type Observer2 struct{}
+
+func (o *Observer2) Update(msg string) {
+	fmt.Printf("%s observer2 update! \n", msg)
+}

go/structural/observer/observer_test.go

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+package observer
+
+import "testing"
+
+func TestSubjectAndObserver(t *testing.T) {
+	s := Subject{}
+
+	o1 := Observer1{}
+	o2 := Observer2{}
+
+
+	s.Register(&o1)
+	s.Register(&o2)
+
+	s.Notify("hello")
+	
+}