/**
* 使用同步机制将单例模式中的懒汉模式改写为线程安全的
* @author hehuasen
* @create 2021-12-01 17:50
*/
public class BankTest {
}
class Bank{
private Bank(){
}
public static Bank instance=null;
// public static Bank getInstance(){
// //方式一:效率稍差
// synchronized (Bank.class){
// if (instance == null) {
// instance=new Bank();
// }
// return instance;
// }
// }
public static Bank getInstance(){
//方式二:效率更高
if (instance == null) {
synchronized (Bank.class){
if (instance == null) {
instance=new Bank();
}
}
}
return instance;
}
}