的時候所以我是一個初學者到Java(未編程),我encoutered一個問題,即它不會讓我創建一個ArrayList:爪哇 - 錯誤創建的ArrayList
import java.io.*;
import java.util.ArrayList;
import java.util.*;
public class OrderingNumbers{
public static void main (String[] args)throws IOException{
boolean keepRunning = true;
List<String> numbers = new ArrayList<String>(); //<--this one does not work
ArrayList sortedNumbers = new ArrayList();//<-- This one works
while(keepRunning){
DataInputStream input = new DataInputStream(System.in);
System.out.print("Do you want to sort the numbers or add a number?");
String answer = input.readLine();
if(answer.equals("sort")){
for(int i = 0; i < numbers.size(); i++){
System.out.println(numbers.get(i));
}
System.out.println("Bye Bye.");
keepRunning = false;
}else if(answer.equals("add")){
System.out.print("What number to you want to add?");
numbers.add(input.readLine());
System.out.println("Added number.");
}else{
System.out.print("That is not an option.");
}
}
}
}
我試圖這樣做,以及,ArrayList<String> strArrayList = new ArrayList<String>();
但仍然無法正常工作。我想讓用戶可以添加另一個數字,如果他們想要的數組。
請勿使用原始類型。它怎麼不起作用? –
你正在編譯哪個版本的java? – Jack
@ElliottFrisch它說這是一個無效的assigment運算符 –