文檔查閱說明:
定義:將一個複雜對象的構建與它的表示分離,使得同樣的構建過程可以創建不同的表示
使用場景:
● 相同的方法,不同的執行順序,產生不同的事件結果時;
● 多個部件或零件,都可以裝配到一個對象中,但是產生的運行結果又不相同時;
● 產品類非常複雜,或者產品類中的調用順序不同產生了不同的效能
● 需要生成的對象具有複雜的內部結構;
● 需要生成的對象內部屬性本身相互依賴
public class Product {
List<String> list = new ArrayList<>();
public void add(String part) {
list.add(part);
}
public void show() {
for(String part: list) {
System.out.println("部件:"+part);
}
}
}
public abstract class Builder {
public abstract void buildPartA();
public abstract void buildPartB();
public abstract Product getProduct();
}
public class ConCreateBuilderA extends Builder {
private Product product = new Product();
@Override
public void buildPartA() {
// TODO Auto-generated method stub
product.add("頭");
product.add("軀幹");
product.add("雙手");
product.add("雙腳");
}
@Override
public void buildPartB() {
// TODO Auto-generated method stub
product.add("悠閒褲");
product.add("純色襯衫");
product.add("板鞋");
}
@Override
public Product getProduct() {
// TODO Auto-generated method stub
return product;
}
}
public class ConCreateBuilderB extends Builder {
private Product product = new Product();
@Override
public void buildPartA() {
// TODO Auto-generated method stub
product.add("龍頭");
product.add("龍軀幹");
product.add("龍雙手");
product.add("龍雙腳");
}
@Override
public void buildPartB() {
// TODO Auto-generated method stub
product.add("尾巴");
product.add("雙翼");
}
@Override
public Product getProduct() {
// TODO Auto-generated method stub
return product;
}
}
public class Director {
public void construct(Builder builder) {
builder.buildPartA();
builder.buildPartB();
}
}
public class Test {
public static void main(String[] args) {
Director director = new Director();
Builder b1 = new ConCreateBuilderA();
Builder b2 = new ConCreateBuilderB();
director.construct(b1);
Product p1 = b1.getProduct();
p1.show();
director.construct(b2);
Product p2 = b2.getProduct();
p2.show();
}
}