版权声明: https://blog.csdn.net/qq_38977441/article/details/84787063
为了让自己记住单例模式特意记录
线程不安全版
public class singleton{
private static Singleton instance;
private singleton(){};
public static Sinleton getInstance(){
if (instance==null){
instance=new singleton; }
return instance;
}
}
线程安全版
public class singleton{
private static Singleton instance;
private singleton(){};
public static synchronized Sinleton getInstance(){
if (instance==null){
instance=new singleton; }
return instance;
}
}
1无法实现多线程,不安全。
2.实现多线程,效率低下。