題目：產生一個名為Elephant的Class延伸至Animal Class
此類別有一個成員變數為name
有一個覆寫成員方法speak，用以列印父類別的兩個成員變數和自己的成員變數
最後再main()中分別透過建構子產生兩個Animal
- Animal年紀3歲體重8.0公斤
- 另一個為Elephant年紀、體重、名字為8歲,1200.0公斤,大象
思考進程：
- 產生Elephant class 繼承Animal
- 寫出建構式並繼承Animal的建構式
- 覆寫方法speak()
- new出新物件並使用方法
Animal.java
public class Animal{
int age = 0;
float weight = 0;
void speak() {
System.out.println("age: " + age);
System.out.println("weight:" + weight);
}
Animal( int age, float weight){
this.age=age;
this.weight=weight;
}
}
Elephant.java
public class Elephant extends Animal{
String name="";
Elephant( int age, float weight ,String name){
super(age,weight);
this.name=name;
}
void speak() {
System.out.println("age: " + age);
System.out.println("weight:" + weight);
System.out.println("name:" + name);
}
}
AnimalTest.java
public class AnimalTest {
public static void main (String args[]) {
Animal animal1 = new Animal(3 , 8.0f);
Elephant elephant = new Elephant(8,1200.0f,"大象");
animal1.speak();
elephant.speak();
}
}