如何将一个类中一个方法的返回值连接到另一个类中的另一方法？

Question

我正在尝试使类方法playerTurn与另一个类交互。

import java.util.*;

public boolean PlayerTurn(){

    System.out.println("To determine who goes first, I am thinking of a number between 1 and 5, including 1 and 5.");
    int comp1 = rand.nextInt(5)+1;
    System.out.println(player1+", input guess: ");
    int g1 = scan.nextInt();
    System.out.println(player2+", input guess: ");
    int g2 = scan.nextInt();

    int p1 = Math.abs (comp1 -g1);
    int p2 = Math.abs(comp1-g2);
if(p1<p2){

    System.out.println("The number was "+comp1+". " +player1+", will go first.");

    return true ;



}
else 
    System.out.println("The number was "+comp1+". "+player2+", will go first.");
    return true;


}

它可以打印出正确的内容，但我需要与此相关的内容。 如果为true，则player1首先进入，那就是第一个if语句，但是它甚至没有运行，而是返回到PlayerTurn方法，即使它没有第二次被调用：

public class fullCard {
     ArrayList<Integer>cardDraw1 = new ArrayList<Integer>(12);
     ArrayList<Integer>cardDraw2 = new ArrayList<Integer>(12);
     Random rand = new Random();
    Scanner scan = new Scanner(System.in);
    Intro test = new Intro();
    Player p = new Player();

int MysteryCard, ans1, ans2;
int total1, total2, newHighCard, newLowCard;

public fullCard(){

    int total1= 0, total2= 0;
    int newHighCard=0;
    int newLowCard=0;
    MysteryCard = rand.nextInt(13)+1;
}


public String MysteryDeck(){

for(int i =0; i<12; i++){   
    System.out.println("Why");<--this prints
    if(p.PlayerTurn())//DOES NOT WORK AT ALL
        System.out.print(" Player 1   Type 1 to pick from a deck higher than the MysteryCard and Type 2 to draw from a deck lower.");
        ans1 = scan.nextInt();
        if(ans1 ==1)
            System.out.println("You have chosen to pick from cards between"+MysteryCard+" and 13");
            for(int k= 0; k < cardDraw1.size(); k++)
                newHighCard = rand.nextInt(13-MysteryCard)+(MysteryCard+1);
                cardDraw1.add(newHighCard);
            for(int v=0; v<cardDraw1.size(); v++)
                total1+=cardDraw1.get(v);
                System.out.println(total1);

        if(ans1== 2)
            System.out.println("You will draw from a deck 1 to "+MysteryCard);
            for(int k= 0; k<cardDraw1.size();k++)
                newLowCard = rand.nextInt(MysteryCard+1)+1;
                cardDraw1.add(newLowCard);

            for (int v=0; v<cardDraw1.size(); v++)
                total1+=cardDraw1.get(v);
        System.out.println(total1);



    if(!p.PlayerTurn())
        System.out.println("Player 2  Type 1 to pick from a deck higher than the MysterCard and type 2 to draw from a deck lower than the MysteryCard.");
        ans2=scan.nextInt();    
        if(ans2 ==1)
            System.out.println("You have chosen to pick from cards between "+MysteryCard+" and 13");
            for(int k= 0; k<cardDraw2.size(); k++)
                newHighCard = rand.nextInt(13-MysteryCard)+(MysteryCard+1);
                cardDraw2.add(newHighCard);

            for(int d = 0; d<cardDraw2.size(); d++)
                total2 +=cardDraw2.get(d);

                System.out.println(total2);
        if(ans2== 2)
            System.out.println("You will draw from a deck 1 to "+MysteryCard);
            for(int k= 0; k<cardDraw2.size(); k++)
                newLowCard = rand.nextInt(MysteryCard+1)+1;
                cardDraw2.add(newLowCard);
                System.out.println(cardDraw2);
}   

return ("");

}

}

Answer 1

您忘记在PlayerTurn()方法中为else block添加{} 。

else
{ // add this
    System.out.println("The number was "+comp1+". "+player2+", will go first.");
    return true;
} // and this

如果要一起执行多条指令，请确保在其余的代码中添加{} for if block ， else block和for loop block 。

例如，让我们获取这段代码

if(ans1 ==1)
            System.out.println("You have chosen to pick from cards between"+MysteryCard+" and 13");
            for(int k= 0; k < cardDraw1.size(); k++)
                newHighCard = rand.nextInt(13-MysteryCard)+(MysteryCard+1);
                cardDraw1.add(newHighCard);
            for(int v=0; v<cardDraw1.size(); v++)
                total1+=cardDraw1.get(v);
                System.out.println(total1);

在这里，只有System.out.println("You have chosen to pick from cards between"+MysteryCard+" and 13"); 每当ans1 ==1时将执行。

我认为您想按以下步骤进行操作（添加{} ）

 if(ans1 ==1)
 { //add this
                System.out.println("You have chosen to pick from cards between"+MysteryCard+" and 13");
                for(int k= 0; k < cardDraw1.size(); k++)
                    newHighCard = rand.nextInt(13-MysteryCard)+(MysteryCard+1);
                    cardDraw1.add(newHighCard);
                for(int v=0; v<cardDraw1.size(); v++)
                    total1+=cardDraw1.get(v);
                    System.out.println(total1);
}// ans this

这就是整个MysteryDeck()方法，其中添加了您错过的{} 。

public String MysteryDeck(){

for(int i =0; i<12; i++){   
    System.out.println("Why");<--this prints
    if(p.PlayerTurn())
    { // here
        System.out.print(" Player 1   Type 1 to pick from a deck higher than the MysteryCard and Type 2 to draw from a deck lower.");
        ans1 = scan.nextInt();
        if(ans1 ==1)
        { // here
            System.out.println("You have chosen to pick from cards between"+MysteryCard+" and 13");
            for(int k= 0; k < cardDraw1.size(); k++)
            { // here
                newHighCard = rand.nextInt(13-MysteryCard)+(MysteryCard+1);
                cardDraw1.add(newHighCard);
            } // here
            for(int v=0; v<cardDraw1.size(); v++)
            {// here optional
                total1+=cardDraw1.get(v);
            } //here optional
                System.out.println(total1);
        } // here


        if(ans1== 2)
        { // here
            System.out.println("You will draw from a deck 1 to "+MysteryCard);
            for(int k= 0; k<cardDraw1.size();k++)
            { // here
                newLowCard = rand.nextInt(MysteryCard+1)+1;
                cardDraw1.add(newLowCard);
            } // here
            for (int v=0; v<cardDraw1.size(); v++)
            { // here optional
                total1+=cardDraw1.get(v);
            } // here optional
            System.out.println(total1);
        } // here

    } // here

    if(!p.PlayerTurn())
    { // here
        System.out.println("Player 2  Type 1 to pick from a deck higher than the MysterCard and type 2 to draw from a deck lower than the MysteryCard.");
        ans2=scan.nextInt();    
        if(ans2 ==1)
        { // here
            System.out.println("You have chosen to pick from cards between "+MysteryCard+" and 13");
            for(int k= 0; k<cardDraw2.size(); k++)
            { // here
                newHighCard = rand.nextInt(13-MysteryCard)+(MysteryCard+1);
                cardDraw2.add(newHighCard);
            } // here

            for(int d = 0; d<cardDraw2.size(); d++)
            { // here optional
                total2 +=cardDraw2.get(d);
            } // here optional

                System.out.println(total2);
        } // here
        if(ans2== 2)
        { // here
            System.out.println("You will draw from a deck 1 to "+MysteryCard);
            for(int k= 0; k<cardDraw2.size(); k++)
            { // here
                newLowCard = rand.nextInt(MysteryCard+1)+1;
                cardDraw2.add(newLowCard);
            } // here
                System.out.println(cardDraw2);
        }//here
    }// here
}   

return ("");

}