Java中是否有命令使程序返回循環的開頭

Question

我正在嘗試用Java進行打字冒險類游戲，但是我至少需要一個與標題中的命令相似的命令，這是代碼

import java.util.Scanner;

public class MyFirstGameInJava {

public static void main(String[] args) {

System.out.println("Greetings, Enter your name and you may start your quest!");
Scanner Username = new Scanner(System.in);
String name = Username.nextLine();
System.out.println("Greetings " + name );
System.out.println("Welcome to an Unnamed Typing Advanture");
System.out.println("You find yourself on an island with very few trees, you can either hit a tree, or walk along");

String sc = Username.nextLine();

switch(sc){

case "Hit tree":
System.out.println("A coconut falls from the tree");
System.out.println("You can either eat the coconut or throw it");
break;
case "Walk":
System.out.println("You walk for a mile and find a village");
System.out.println("The village appears empty, you can either scream to see if anybody is there, or you can keep walking");
break;
default :
System.out.println("Nothing happens...");
}   

String sc1 = Username.nextLine();


switch(sc1){

case "Eat coconut":
System.out.println("You ate the coconut and got poisoned");
System.out.println("You died...");
break;
case "Throw coconut":
System.out.println("By throwing the coconut, you awaken a tiger and he eats you");
System.out.println("You are dead");
break;
case "Scream":
System.out.println("As soon as you scream, a man shoots you down from a window from one of the houses");
System.out.println("You died...");
break;
case "Walk":
System.out.println("You walked through the village, and you find a boat and leave the island");
System.out.println("You win! Updates coming soon!");
break;
default:
System.out.print("Nothing happend");



}

}

}

每當用戶鍵入除要求之外的其他內容時，就會發生默認情況，但是我需要它返回到循環的開始，因此用戶可以鍵入其他情況之一。

Answer 1

您可以使用continue語句繼續進行下一個迭代。

就是說，我沒有在示例代碼中看到循環。 您可以使用for ， while或do/while循環。 do / while循環至少執行一次-這通常是在詢問用戶問題時要執行的操作。

本Java分支語句教程提供了for循環中的continue語句示例。

   for (int i = 0; i < max; i++) {
        // interested only in p's
        if (searchMe.charAt(i) != 'p')
            continue;

        // process p's
        numPs++;
    }

Answer 2

使用continue; 以無條件循環為例

while(true){/* your code*/}

Answer 3

您的問題做出了錯誤的假設。 switch()語句不是循環。 這是一堆if / else-if語句的簡寫：

if(sc1.equals("Eat coconut")) {
    System.out.println("You ate the coconut and got poisoned");
    System.out.println("You died...");
}
else if(sc1.equals("Throw coconut")) {
//and so on

要執行所需的操作，您將需要一個實際的while()或for()循環。 （這些鏈接將帶您進入解釋這兩種構造的Java教程。）

Answer 4

我的CS課也遇到了同樣的問題：這就是我所做的。 首先，您需要使用循環。 我使用了一個“ while”循環。

因此，假設您在對話中的某個時刻，有人要問別人（例如武術大師問玩家），而答案選擇是“ y”或“ n”。 但是玩家輸入“ m”。 這將產生一個錯誤。 要解決此問題，您需要進行一些操作（循環），以繼續檢查用戶是否鍵入了有效的響應，並相應地繼續執行程序。 現在的代碼...

//Ask if they want to see the rules.    
System.out.println("Welcome Player One");  
System.out.println("Would you like to read the rules of the gem?");  
System.out.println("[y]Yes, please / [n]I know the rules."); //So you made it clear that the choices are 'y' or 'n' (yes or no).

//Decide if they hit yes or no.  
char Response; //Variable to hold user response.  
Scanner Console = new Scanner(System.in); //I don't know why, exactly, but you need this.  
Response = Console.next().charAt(0); //Set response to the user input. A input field will appear.  
while(true){  //Making the parameter 'true' makes the flow of the loop depend on the parameters in the if statements (I think).  
  if(Response == 'y' || Response == 'Y'){  
   System.out.println("Here are the rules:");  
   break; //break will make the flow exit the while loop (so you can continue adding the rest of your code).  
  }  
  else if(Response == 'n' || Response == 'N'){  
   System.out.println("Then let us continue:");  
   break;  
  }  
  else{  
   System.out.println("Would you like to read the rules of the gem?"  
   System.out.println("You have to enter (y)yes or (n)no...");  
   Response = Console.next().charAt(0); //Just like before, input field will  appear to give them the chance to change their response to a valid one.  
   continue; //This has to be 'continue' so that the loop will continue to "check" for the value that needs to be input by the user.  
  }  
}

希望這會有所幫助，歡呼。

Answer 5

不太詳細，更直接。 我已經解釋了簡單的答案。

for(int i = 0; i <= 10; i++){
        if(i == 4){
            continue;
        }
        //Should skip 4 and print out 1,2,3,5,6,7,8,9,10
        System.out.println(i);
    }