创建型模式-工厂方法 （python实现 与 java实现）

python 实现

`
import abc

抽象类，定义方法，不具体实现方法，继承类具体实现方法

class Shape(metaclass=abc.ABCMeta):
@abc.abstractmethod
def draw(self):
pass

工厂类

class Rectangle(Shape):
"""A simple"""

def draw(self):
    print("Inside Rectangle::draw() method.")

工厂类

class Square:
"""A simple localizer a la gattext"""

def draw(self):
    print("Inside Square::draw() method.")

class ShapeFactory:
def getShape(self, shapeType: str):
if shapeType == None:
return
if shapeType.upper() == "RECTANGLE":
return Rectangle()
elif shapeType.lower() == "square":
return Square()
return

if name == 'main':
# 实例化工厂类
shapeFactory = ShapeFactory()
shape1 = shapeFactory.getShape("rectangle")
shape1.draw()

shape2 = shapeFactory.getShape("square")
shape2.draw()

`

java 实现

main.java

`
public interface Shape {
void draw();
}

public class Rectangle implements Shape{
@Override
public void draw() {
System.out.println("Inside Rectangle::draw() method.");
}
}

public class ShapeFactory {
public Shape getShape(String shapeType){
if (shapeType==null){
return null;
}
if (shapeType.equalsIgnoreCase("square")){
return new Square();
}
else if (shapeType.equalsIgnoreCase("rectangle")){
return new Rectangle();
}
return null;
}
}

public class Main {
public static void main(String[] args){
// 创建工厂类实例
ShapeFactory shapeFactory = new ShapeFactory();
// 使用工厂类实例 方法获取具体的 细节类
Shape shape1 = shapeFactory.getShape("Rectangle");
// 细节类调用
shape1.draw();

    // 使用工厂类实例 方法获取具体的 细节类
    Shape shape2 = shapeFactory.getShape("square");
    // 细节类调用
    shape2.draw();
}

}

`