Spring data jpa 時間注解

先定義一個構造函數(shù)：

function Person(name,age){    this.name = name;    this.age = age;    this.say = function(){        console.log("hello world")    }}Person.prototype.gender = male;

1.原型鏈繼承：將子類的構造函數(shù)的原型變?yōu)楦割惖膶嵗龑ο?/span>

Student.prototype = new Person();Student.prototype.constructor = Student

優(yōu)點:實現(xiàn)簡單
缺點:無法向父構造函數(shù)傳參

2.通過構造函數(shù)繼承

function Student(name,age){    Person.call(this,name,age)    this.name = name;    this.age = age;    this.say = function(){        console.log("hello world")    }}

缺點:無法訪問父構造函數(shù)的原型中的方法

3.將子構造函數(shù)的原型修改為父構造函數(shù)的原型

function Student(name,age){    Person.call(this,name,age)    this.name = name;    this.age = age;    this.say = function(){        console.log("hello world")    }}Student.prototype = Person.prototypeStudent.prototype.constructor = Student

缺點:破壞了原型鏈，給子類的原型添加屬性父類原型也會添加

4.將子類的原型設置為父類的實例對象

function Student(name,age){    Person.call(this,name,age)    this.name = name;    this.age = age;    this.say = function(){        console.log("hello world")        }    }  Student.prototype = new Person();

缺點：調(diào)用了兩次父類構造函數(shù)，消耗內(nèi)存