Extends 继承 (1)

“Extends” simulates the relationship between the things in real world.
父类: Superclass
子类: Subclass
A Java superclass is a class which gives a method or methods to a Java subclass. A Java class may be either a subclass, a superclass, both, or neither!

———-TestExtends.java———-
package ch.allenstudy.newway02;

public class TestExtends {
public static void main(String[] args)
{
Graduate gd = new Graduate();
System.out.printf(“%s %f\n”, gd.name, gd.score);
}
}

class Human
{
public String name = “zhangsan”;
public int age = 22;

}

class Student extends Human //学生，继承人类
{
public double score = 66.6;
}

class Graduate extends Student //研究生，继承学生
{
public String daoshi = “Allen”;
}
——–Result——-
zhangsan 66.600000