간단하다... 론 패턴.. loan pattern
package com.javaTest.lamda;
public class Person {
public Person(String name, int age) {
this.name = name;
this.age = age;
}
public Person() {
}
String name;
int age;
public String getName() {
return name;
}
public Person setName(String name) {
this.name = name;
return this;
}
public int getAge() {
return age;
}
public Person setAge(int age) {
this.age = age;
return this;
}
@Override
public String toString() {
return "{name:"+this.name+",age:"+this.age+"}";
//return super.toString();
}
public int ageDifference(Person other) {
return age - other.age;
}
}
자 흔한 vo 인데... 잘보면 return this; 즉 자신을 리턴하고 있다. 객체를...
public void chaining001() {
Person person = new Person().setAge(10).setName("dr.who");
System.out.println(person.toString());
}
자.. 이렇게 체이닝이 만들어진다. 간단하지?
근데 문제는... 만약 vo 가 확장 vo 라면?
확장시 타입을 확실히 선언해주면된다. ( 참고 https://stackoverflow.com/questions/1069528/method-chaining-inheritance-don-t-play-well-together )
// XXX base 가 되는 클래스는 타입을 선언해줘야함
class Pet<T extends Pet>
{
private String name;
private String color;
public T setName(String name) {
this.name = name;
return (T) this;
}
public String getName() {
return name;
}
public String getColor() {
return color;
}
public T setColor(String color) {
this.color = color;
return (T) this;
}
}
// XXX 확장한 클래스는 베이스 클래스에게 타입을 알려줘야함(여기서는 Cat)
class Cat extends Pet<Cat>
{
private String sand;
private String hair;
public String getSand() {
return sand;
}
public Cat setSand(String sand) {
this.sand = sand;
return this;
}
public String getHair() {
return hair;
}
public Cat setHair(String hair) {
this.hair = hair;
return this;
}
}
class Dog extends Pet<Dog>
{
private String takeawalk;
private String vitality;
public String getTakeawalk() {
return takeawalk;
}
public Dog setTakeawalk(String takeawalk) {
this.takeawalk = takeawalk;
return this;
}
public String getVitality() {
return vitality;
}
public Dog setVitality(String vitality) {
this.vitality = vitality;
return this;
}
}
@Test
public void chaining001() {
Person person = new Person().setAge(10).setName("dr.who");
System.out.println(person.toString());
Cat cat = new Cat();
cat.setName("shasha").setHair("short").setSand("normal").setColor("mix");
Dog dog = new Dog();
dog.setName("jindol").setVitality("very good").setColor("brown").setTakeawalk("daily");
}
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. – Bart Robinson Apr 10 at 18:46