單例模式:
單例模式是設計模式中最簡單的模式之一,其中由(餓漢式單例模式、懶漢式單例模式······【就敲了這兩個,還有別的··】)
餓漢式單例模式;靜態對象,在聲明時創建。(在類被加載的時候創建其對象)
懶漢式單例模式;又稱爲延遲加載。
對比;懶漢式更消耗內存時間,餓漢式更消耗運行時間。
懶漢式單例模式:
package Danlimoshi;
public class Lanhanmoshi
{
private static volatile Lanhanmoshi instance=null;
private Lanhanmoshi(){}
public static synchronized Lanhanmoshi getInstance()
{
if(instance==null)
{
instance=new Lanhanmoshi();
}
return instance;
}
}
餓漢單例模式:
package Danlimoshi;
public class Ehanmoshi
{
private static final Ehanmoshi instance=new Ehanmoshi();
private Ehanmoshi(){}
public static Ehanmoshi getInstance()
{
return instance;
}
}
public class Student {
static Student student = new Student();
//私有化構造方法,使得無法使用new來創建對象
private Student() {
}
public static Student getInstanceOfStudent() {
if (student == null)
student = new Student();
return student;
}
}