建造者模式

　　建造者模式适用于需要生成的产品对象有复杂的内部结构。

//产品
public class AirShip {
    private Engine engine;    //发动机
    private Cabin cabin;    //机舱
    private Excape excape;    //逃生舱
    public Engine getEngine() {
        return engine;
    }
    public void setEngine(Engine engine) {
        this.engine = engine;
    }
    public Cabin getCabin() {
        return cabin;
    }
    public void setCabin(Cabin cabin) {
        this.cabin = cabin;
    }
    public Excape getExcape() {
        return excape;
    }
    public void setExcape(Excape excape) {
        this.excape = excape;
    }
}
class Engine{
    String name;
}
class Cabin{
    String name;
}
class Excape{
    String name;
}

//产品建造
public interface AirShipBuilder {
    Engine createEngine();
    Cabin createCabin();
    Excape createExcape();
}

//指挥者
public interface Director {
    AirShip createAirship();
}

//具体的指挥者
public class SxtDirector implements Director{
    AirShipBuilder builder;
    //根据不同的建造者
    public SxtDirector(AirShipBuilder builder) {
        this.builder = builder;
    }
    //相同的安装顺序
    @Override
    public AirShip createAirship() {
        AirShip ship = new AirShip();
        ship.setCabin(builder.createCabin());
        ship.setEngine(builder.createEngine());
        ship.setExcape(builder.createExcape());
        return ship;
    }
}

//具体的建造者
public class SxtAirShipBuilder implements AirShipBuilder{
    @Override
    public Engine createEngine() {
        System.out.println("engine is building");
        return new Engine();
    }
    @Override
    public Cabin createCabin() {
        System.out.println("cabin is building");
        return new Cabin();
    }
    @Override
    public Excape createExcape() {
        System.out.println("excape is building");
        return new Excape();
    }
}

//用户只需要与指挥者和建造者打交道就可以得到结构复杂的产品 
public class BuilderDemo {
    public static void main(String[] args) {
        AirShipBuilder bu = new SxtAirShipBuilder();
        AirShip ship = new SxtDirector(bu).createAirship();
    }
}