设计模式之模板方法

1类图

2scala示例

package design
trait BuildCar{
def build()={
println("start to build a car");
buildHead();
buildBody();
buildBottom();
println("finish build a car");
}
def buildHead();
def buildBody();
def buildBottom();
}

class BuildBMWCar extends BuildCar{
def buildHead()={
println("I am building bmw head.");
}
def buildBody()={
println("I am building bmw body.");
}
def buildBottom()={
println("I am building bmw bottom.");
}
}
object TemplateMethod {
def main(args: Array[String]): Unit = {
val builder:BuildCar=new BuildBMWCar();
builder.build();
}
}