以画图形为例：Shape 接口和实现 Shape 接口的实体类Rectangle、Square、Circle
类图
- 形状接口
public interface Shape {
void draw();
}
- 实现类
public class Circle implements Shape {
@Override
public void draw() {
System.out.println("Draw Circle!");
}
}
public class Square implements Shape {
@Override
public void draw() {
System.out.println("Draw Square!");
}
}
public class Rectangle implements Shape {
@Override
public void draw() {
System.out.println("Draw Rectangle!");
}
}
- 工厂
public class ShapeFactory {
public Shape getShape(String shapeType){
switch (shapeType.toUpperCase()){
case "CIRCLE":
return new Circle();
case "RECTANGLE":
return new Rectangle();
case "SQUARE":
return new Square();
default:
return null;
}
}
}
- 测试类
public class TestFactory {
public static void main(String[] args) {
ShapeFactory shapeFactory = new ShapeFactory();
//图形：rectangle
Shape shape1 = shapeFactory.getShape("rectangle");
shape1.draw();
//图形：circle
Shape shape2 = shapeFactory.getShape("circle");
shape2.draw();
//图形：square
Shape shape3 = shapeFactory.getShape("square");
shape3.draw();
}
}
- 结果:
Draw Rectangle!
Draw Circle!
Draw Square!
