从用户输入java修改arraylist

萨莎·克鲁兹（Sasha Cruz）

用我的代码运行菜单。但是，当用户键入水果名称（保留）时，我希望用户按下“ V”（去查看所有水果）时说“保留”

我已经阅读了Oracle Java Collections Arraylist，根据我的理解，我必须使用get方法或equals方法进行编码，但是我不太确定该怎么做（尽管我确实尝试过）

请帮忙！

import java.util.ArrayList;
import java.util.Scanner;
public class FruitApril {
public static void main(String[] args) {

     TheMenu();  
 }
public static void TheMenu()
{
    String Customer[] = new String[10]; 
    Scanner input = new Scanner(System.in);
    ArrayList<String> fruits = initFruits();


    String option; 
    do {   // loop back to here as long as Q isn't selected           
    System.out.println("\nMenu");
    System.out.println("V: Views all fruit");
    System.out.println("R: To reserve fruit"); 
    System.out.println("Q: To exit");

    option = input.next();  

    if (option.charAt(0) == 'V' ) 
    { 
        viewAllFruit(fruits,Customer);
    } 


    if (option.charAt(0) == 'R' ) 
    { 
        reserveFruit(fruits,Customer);
    }

    }
    while (option.charAt(0) != 'Q');
    }   



    public static ArrayList<String> initFruits() {
    ArrayList<String> theFruit = new ArrayList<String>();
    theFruit.add("Plums");
    theFruit.add("Grapes");
    theFruit.add("Oranges");
    theFruit.add("Prunes");
    theFruit.add("Apples");
    return theFruit;
  }

 public static void viewAllFruit(ArrayList<String> fruits, String
 CustomerRef[])
  {
    for (String fruit : fruits) {
        System.out.println("Fruit " + fruit + " is in stock ");   
    }
  }

 public static void reserveFruit(ArrayList<String> fruits,String
  CustomerRef[])
{

    Scanner input = new Scanner(System.in);

    while(true) {
        System.out.println("Please enter the name of the fruit you'd like 
        to reserve");
        String Fruitn = input.next();

        if (Fruitn.equals(fruits))
        {
            fruits.get(Fruitn);
      }
   }
}

普拉萨德

嗨，
我已经更改了您的代码

import java.util.ArrayList;
import java.util.Scanner;
public class FruitApril {
public static void main(String[] args) {

 TheMenu();  
}
public static void TheMenu()
{
String Customer[] = new String[10]; 
Scanner input = new Scanner(System.in);
ArrayList<String> fruits = initFruits();


String option; 
do {   // loop back to here as long as Q isn't selected           
System.out.println("\nMenu");
System.out.println("V: Views all fruit");
System.out.println("R: To reserve fruit"); 
System.out.println("Q: To exit");

option = input.next();  

if (option.charAt(0) == 'V' ) 
{ 
    viewAllFruit(fruits,Customer);
} 


if (option.charAt(0) == 'R' ) 
{ 
    reserveFruit(fruits,Customer);
}
if(option.charAt(0) == 'Q') // added this condition
{
    System.exit(0);
}

}while (option.charAt(0) == 'Q');

}

public static ArrayList<String> initFruits() {
ArrayList<String> theFruit = new ArrayList<String>();
theFruit.add("Plums");
theFruit.add("Grapes");
theFruit.add("Oranges");
theFruit.add("Prunes");
theFruit.add("Apples");
return theFruit;

}

 public static void viewAllFruit(ArrayList<String> fruits, String CustomerRef[])
  {
for (String fruit : fruits) {
    System.out.println("Fruit " + fruit + " is in stock ");   
}
  }

 public static void reserveFruit(ArrayList<String> fruits,String  CustomerRef[])
{

    Scanner input = new Scanner(System.in);

   while(true) {
    System.out.println("Please enter the name of the fruit you'd like to reserve");
    String Fruitn = input.next();
int index = fruits.indexOf(Fruitn);//added this line
    if (index>=0)// added this condition
    {
        String fruit = fruits.get(index); //added this line
    System.out.println("Reversed Fruit:"+fruit); // do according to your requirement
    }
  }
}
}

我已经从用户那里接受了输入。使用该输入，我在ArrayList中找到了水果的索引，然后我使用了get方法来获取该水果。您没有提到对反转字符串的要求。所以我只放了sopComplete其余代码根据您的要求。

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