Python
>>> help(5)
Help on int object:
(etc etc)
>>> dir(5)
['__abs__', '__add__', ...]
>>> abs.__doc__
'abs(number) -> number
Return the absolute value of the argument.'
1、单例模式 public class Singleton {
private static Singleton st;//懒汉式
private Singleton(){}
public static Singleton getInstance(){
if(st==null)
{st=new Singleton();}
return st;
}
public sta
