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https://github.com/chai2010/advanced-go-programming-book.git
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57 lines
806 B
Go
57 lines
806 B
Go
// Copyright © 2017 ChaiShushan <chaishushan{AT}gmail.com>.
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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package main
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import (
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"sync"
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)
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type ObjectId int32
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var refs struct {
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sync.Mutex
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objs map[ObjectId]interface{}
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next ObjectId
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}
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func init() {
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refs.Lock()
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defer refs.Unlock()
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refs.objs = make(map[ObjectId]interface{})
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refs.next = 1000
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}
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func NewObjectId(obj interface{}) ObjectId {
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refs.Lock()
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defer refs.Unlock()
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id := refs.next
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refs.next++
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refs.objs[id] = obj
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return id
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}
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func (id ObjectId) IsNil() bool {
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return id == 0
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}
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func (id ObjectId) Get() interface{} {
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refs.Lock()
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defer refs.Unlock()
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return refs.objs[id]
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}
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func (id ObjectId) Free() interface{} {
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refs.Lock()
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defer refs.Unlock()
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obj := refs.objs[id]
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delete(refs.objs, id)
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return obj
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}
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