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Java/练习题：抽象类与接口.md

@@ -46,10 +46,133 @@ public class GoShopping {
 
 #### 练习1：
 创建 Shape（图形）类，该类中有一个计算面积的方法。圆形和矩形都继承自图形类，输出圆形和矩形的面积。
+```java
+
+public class Circle extends Shape {
+	double radius;
+	
+	public Circle(double radius) {
+		this.radius = radius;
+	}
+
+	@Override
+	public double getArea() {
+		return Math.PI * this.radius * this.radius;
+	}
+}
+
+
+
+public class Rectangle extends Shape {
+	double length;
+	double width;
+
+	public Rectangle(double length, double width) {
+		this.length = length;
+		this.width = width;
+	}
+
+	@Override
+	public double getArea() {
+		return this.length * this.width;
+	}
+}
+
+
+
+public abstract class Shape {
+	String name;
+	
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+
+	public abstract double getArea();
+}
+
+
+
+public class Test {
+	public static void main(String[] args) {
+		Circle circle = new Circle(1.5);
+		circle.name = "圆形";
+		System.out.println(circle.name + "面积：" + circle.getArea());
+		Rectangle rectangle = new Rectangle(5.5, 2);
+		rectangle.name = "矩形";
+		System.out.println(rectangle.name + "面积：" + rectangle.getArea());
+	}
+}
+
+```
 
 #### 练习2：
 创建工厂类，工厂类中有一个抽象的生产方法，创建汽车厂和鞋厂类，重写工厂类中的抽象生产方法，输出汽车厂生产的是汽车，鞋厂生产的是鞋。
 
+```java
+
+public class AutoPlant extends Factory {
+	String productsName;
+	
+	public AutoPlant(String productsName) {
+		this.productsName = productsName;
+	}
+
+	@Override
+	public String produce() {
+		return this.productsName;
+	}
+}
+
+
+
+public abstract class Factory {
+	String name;
+	
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+
+	public abstract String produce();
+}
+
+
+
+public class ShoeFactory extends Factory {
+	String productsName;
+	
+	public ShoeFactory(String productsName) {
+		this.productsName = productsName;
+	}
+	
+	@Override
+	public String produce() {
+		return this.productsName;
+	}
+}
+
+
+
+public class Test {
+	public static void main(String[] args) {
+		AutoPlant autoPlant = new AutoPlant("汽车");
+		autoPlant.setName("汽车厂");
+		System.out.println(autoPlant.getName() + "生产的是" + autoPlant.productsName);
+		ShoeFactory shoeFactory = new ShoeFactory("鞋");
+		shoeFactory.setName("鞋厂");
+		System.out.println(shoeFactory.getName() + "生产的是" + shoeFactory.productsName);
+	}
+}
+
+```
+