Slide 21
Slide 21 text
もんにょり2: ボイラープレート（定型コード)
public final class Fruit {
private final String name;
private final int price;
private final Country country;
public Fruit(final String name, final int price, final Country country) {
this.name = name;
this.price = price;
this.country = country;
}
public String getName() {
return name;
}
public int getPrice() {
return price;
}
public Country getCountry() {
return country;
}
public Fruit withName(final String name) {
return new Fruit(name, price, country);
}
public Fruit withPrice(final int price) {
return new Fruit(name, price, country);
}
public Fruit withCountry(final Country country) {
return new Fruit(name, price, country);
}
// toStringとか
// equalsとか
// hashCodeとか
public static Builder builder() {
return new Builder();
}
public static class Builder {
private String name;
private int price;
private Country country;
public Fruit build() {
return new Fruit(name, price, country);
}
public Builder name(final String name) {
this.name = name;
return this;
}
public Builder price(final int price) {
this.price = price;
return this;
}
public Builder country(final Country country) {
this.country = country;
return this;
}
● データを表現するクラス
● イミュータブルにしたい
● private final フィールド
● コンストラクタ
● getter
● toString, equals, hashCode
● Builderクラス (Lombokライクな)
Fruitクラス