模板模式

模板模式，模板定义一些方法，作为子类实现的虚方法（对客户端隐藏），并提供一个客户端一个统一方法，这个方法调用了相关虚方法，这样，我们就像实现一个模板一样按部就班的实现一个类了。

package template;

/**
 * 模板模式，这是一个汽车模板.
 * @author wwe
 *
 */
public abstract class CarTemplate {
    
    /**
     * 创造骨架，注意，因为建造函数不想暴露给客户端，这里用protected
     * 进行修饰.
     */
    protected abstract void bulidSkeleton();
    
    /**
     * 安装引擎.
     */
    protected abstract void installEngine();
    
    /**
     * 安装车门.
     */
    protected abstract void installDoor();
    
    public void buildCar() {
        bulidSkeleton();
        installEngine();
        installDoor();
    }
}

package template;

public class FerrariEnzo extends CarTemplate{

    @Override
    protected void bulidSkeleton() {
        System.out.println("FerrariEnzo's skeleton has been built!");
        
    }

    @Override
    protected void installEngine() {
        System.out.println("FerrariEnzo's engine has been installed!");
        
    }

    @Override
    protected void installDoor() {
        System.out.println("FerrariEnzo's doors have been installed!");
        
    }

}

package template;

public class Porsches911 extends CarTemplate{

    @Override
    protected void bulidSkeleton() {
        System.out.println("Porches911's skeleton has been built!");
        
    }

    @Override
    protected void installEngine() {
        System.out.println("Porches911's engine has been installed!");
        
    }

    @Override
    protected void installDoor() {
        System.out.println("Porches911's doors have been installed!");
        
    }

}

package template;

public class Client {
    public static void main(String[] args) {
        CarTemplate Enzo = new FerrariEnzo();
        Enzo.buildCar();
        CarTemplate _911 = new Porsches911();
        _911.buildCar();
    }
}

执行结果

FerrariEnzo's engine has been installed!
FerrariEnzo's doors have been installed!
Porches911's skeleton has been built!
Porches911's engine has been installed!
Porches911's doors have been installed!