父類

public class Uncle {
private String name;
private int age;
public Uncle(){
System.out.println("uncle構(gòu)造方法");
}

public void fahongbao(){
    System.out.println("舅舅發(fā)紅包");
}

}

子類一：

public class UncleOne extends Uncle{
public UncleOne(){
super();
System.out.println("uncleone的構(gòu)造方法");
}
public void chouyan(){
System.out.println("大舅喜歡抽煙");
}
public void fahongbao(){
System.out.println("大舅家道中落，發(fā)不起紅包了，該送祝福了");
}
}
多層繼承：

public class UncleUneSon extends UncleOne{
public UncleUneSon(){

    System.out.println("UncleOneSon的構(gòu)造方法");
}
public void fahongbao(){
    System.out.println("大舅的兒子厲害了，接著發(fā)紅包");
}

}

子類二：

public class UncleTwo extends Uncle{
public void hejiu(){
System.out.println("二舅喜歡喝酒");
}
//方法的重寫 復(fù)寫 覆寫
public void fahongbao(){
System.out.println("二舅不僅發(fā)紅包還送茅臺(tái)");
}

}

public class Demo {
public static void main(String[] args) {
/* UncleOne uncleOne=new UncleOne();
uncleOne.fahongbao();
uncleOne.chouyan();

    UncleTwo uncleTwo=new UncleTwo();
    uncleTwo.fahongbao();
    uncleTwo.hejiu();

    UncleUneSon uncleUneSon=new UncleUneSon();
    uncleUneSon.fahongbao();*/
   UncleUneSon uncleUneSon= new UncleUneSon();
}

}
package edu.xcdq;

public class Demo01 {
public static void main(String[] args) {
final double PI=3.14;
//PI=6.25;
final int[]a=new int[]{1,2,3};
a[0]=10;
a[1]=20;
a[2]=30;
int []b=new int[3];

    System.out.println(a[0]);
    System.out.println(a[1]);
    System.out.println(a[2]);
}

}