mirror of
https://github.com/crazybber/go-pattern-examples.git
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48 lines
681 B
Go
48 lines
681 B
Go
package observer
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import "fmt"
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type Subject struct {
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observers []Observer
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context string
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}
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func NewSubject() *Subject {
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return &Subject{
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observers: make([]Observer, 0),
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}
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}
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func (s *Subject) Attach(o Observer) {
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s.observers = append(s.observers, o)
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}
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func (s *Subject) notify() {
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for _, o := range s.observers {
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o.Update(s)
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}
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}
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func (s *Subject) UpdateContext(context string) {
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s.context = context
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s.notify()
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}
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type Observer interface {
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Update(*Subject)
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}
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type Reader struct {
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name string
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}
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func NewReader(name string) *Reader {
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return &Reader{
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name: name,
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}
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}
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func (r *Reader) Update(s *Subject) {
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fmt.Printf("%s receive %s\n", r.name, s.context)
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}
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