线程安全的单例模式写法
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@ThreadSafe
public class SafeLazyInitialization {
private static Resource resource;
public synchronized static Resource getInstance() {
if (resource == null)
resource = new Resource();
return resource;
}
}
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另外一种写法：
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@ThreadSafe
public class EagerInitialization {
private static Resource resource = new Resource();
public static Resource getResource() { return resource; }
}
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延迟初始化的写法：
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@ThreadSafe
public class ResourceFactory {
private static class ResourceHolder {
public static Resource resource = new Resource();
}
public static Resource getResource() {
return ResourceHolder.resource ;
}
}
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二次检查锁定/Double Checked Locking的写法（反模式）
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public class SingletonDemo {
private static volatile SingletonDemo instance = null;//注意需要volatile
private SingletonDemo() { }
public static SingletonDemo getInstance() {
if (instance == null) { //二次检查，比直接用独占锁效率高
synchronized (SingletonDemo .class){
if (instance == null) {
instance = new SingletonDemo ();
}
}
}
return instance;
}
}
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本文作者：StanWind
文章标题： 线程安全的单例模式写法
本文地址：https://www.stanwind.com/post/67
版权声明：若无注明，本文皆为“Make it Better”原创，转载请保留文章出处。
本文地址：https://www.stanwind.com/post/67
版权声明：若无注明，本文皆为“Make it Better”原创，转载请保留文章出处。
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