设计模式：惰性初始化模式讲解以及Go实现_惰性初始模式(1)，Golang高级工程师面试实战

}

func main() { // 使用配置 config := GetConfig() fmt.Println(config) }

在这个例子中，`sync.Once` 保证了`Config`的实例`configInstance`只会被初始化一次，即使在多线程环境下也能正确工作。这正是Go语言在并发处理上的强项之一。


##### 类图




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uses


















LazyInitializedObject




-static instance: LazyInitializedObject




-LazyInitializedObject()




+static getInstance()
















Client




-LazyInitializedObject obj




+doSomething()









##### 流程图




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请求对象/资源









存在









不存在
































 开始 
 










 检查对象是否存在 
 










 返回现有对象 
 



![img](https://p3-xtjj-sign.byteimg.com/tos-cn-i-73owjymdk6/8cd4ff7b2da3407fbbd07c78a8eaaadc~tplv-73owjymdk6-jj-mark-v1:0:0:0:0:5o6Y6YeR5oqA5pyv56S-5Yy6IEAg5py65Zmo5a2m5Lmg5LmL5b-DQUk=:q75.awebp?rk3s=f64ab15b&x-expires=1771252630&x-signature=OZl%2BmryZgto%2B9fboohUpESo6SQc%3D)
![img](https://p3-xtjj-sign.byteimg.com/tos-cn-i-73owjymdk6/26172eae82504cc1a402ebfa72061de9~tplv-73owjymdk6-jj-mark-v1:0:0:0:0:5o6Y6YeR5oqA5pyv56S-5Yy6IEAg5py65Zmo5a2m5Lmg5LmL5b-DQUk=:q75.awebp?rk3s=f64ab15b&x-expires=1771252630&x-signature=Oywn7eGL1vmKasne0DlzoYAq5f8%3D)

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