java - 骰子声明错误

Question

Dice2 myDice2;
myDice2 = new Dice();

公共(public)类 RecordDice {

public static void main  (String [] args) {
//Declaring the variables of sides and choice
int i;
int choice;
//Declaring the dice2 

Dice2 myDice2;
myDice2 = new Dice();   
//Asking the user for input
System.out.println("How many sides do you want your dice to have?");
Scanner sc = new Scanner(System.in);
i = sc.nextInt();

if (i!= 4 )//||  6|| 8|| 12|| 20|| 100)
{
    System.out.println("You have entered an incorrect number");
}
else 
{
    //myDice2= new Dice(i);
}

//Starting the do statement
    do {
    System.out.print("1- Reroll the dice");
    System.out.print("2- Get the value");
    System.out.print("4- Get the minimum");
    System.out.print("Please make a choice");


    //Gathering the choice for the switch statement
    Scanner s= new Scanner (System.in);
    choice = s.nextInt();

//Starting the switch statement with varying cases dependent on entry   
switch(choice){
    case '1':
        myDice2.reroll();
    System.out.print("1- Reroll the dice");
    System.out.print("2- Get the value");
    System.out.print("4- Get the minimum");
    System.out.print("Please make a choice");

    break;

    case '2':
        myDice2.getValue();
    System.out.print("1- Reroll the dice");
    System.out.print("2- Get the value");
    System.out.print("4- Get the minimum");
    System.out.print("Please make a choice");
    break;

    /*case '3':
        myDice.getMaxValue();
    System.out.print("1- Reroll the dice");
    System.out.print("2- Get the value");
    System.out.print("4- Get the minimum");
    System.out.print("Please make a choice");
    break;

    case '4':
        myDice.getMinValue();
    System.out.print("1- Reroll the dice");
    System.out.print("2- Get the value");
    System.out.print("4- Get the minimum");
    System.out.print("Please make a choice");
    */
    default:
        System.out.println("Invalid choice entered");
}

//If the choice entered isn't the right value it exits the program
}while( choice < 0);

        System.exit(0);
}   }   

RecordDice.java:9:错误:需要类、接口(interface)或枚举 骰子2 myDice2; ^RecordDice.java:10:错误:需要类、接口(interface)或枚举 myDice2 = new Dice(); ^2 个错误

Exit code: 1

当我尝试编译程序时出现上述两个错误。抱歉，很长的帖子和业余代码我只是一个初学者。任何帮助将不胜感激。

Answer 1

在java中，你必须在类内部声明字段，不能在外部删除它们

public class RecordDice {
    public Dice2 myDice2 = new Dice();

<小时/>

看来你的继承是倒退的。如果没有实际看到 Dice 和 Dice2 的类声明，我无法确定，但命名约定表明 Dice2 继承自 骰子

public class RecordDice {
    public Dice myDice2 = new Dice2();