Java-代码不断返回';错误:不兼容的类型:无法将对象转换为int';
在我的代码中,我试图将数组列表的最后一个元素与一个随机数进行比较,但我不断收到错误“不兼容类型:对象无法转换为int”。我似乎找不到解决办法。问题发生在布尔类“checkLastGuess”上Java-代码不断返回';错误:不兼容的类型:无法将对象转换为int';,java,arraylist,Java,Arraylist,在我的代码中,我试图将数组列表的最后一个元素与一个随机数进行比较,但我不断收到错误“不兼容类型:对象无法转换为int”。我似乎找不到解决办法。问题发生在布尔类“checkLastGuess”上 import java.util.Scanner; import java.util.Random; import java.util.ArrayList; public class GuessingGame { int numToGuess = new Random().nextInt(10)
import java.util.Scanner;
import java.util.Random;
import java.util.ArrayList;
public class GuessingGame
{
int numToGuess = new Random().nextInt(10);
ArrayList guesses = new ArrayList();
void getGuess()
{
Scanner keyboard = new Scanner(System.in);
boolean valid = false;
int userGuess = 0;
while (valid == false)
{
System.out.print("What is your guess: ");
String num = keyboard.next();
char new_num = num.charAt(0);
if (Character.isDigit(new_num))
{
userGuess = Integer.parseInt(num);
if (userGuess >= 0 && userGuess < 10)
{
guesses.add(userGuess);
valid = true;
}
else
{
System.out.println("Invalid guess, please enter a number between 0 and 9.");
}
}
else
{
System.out.println("Invalid guess, please enter digit.");
}
}
}
void printGuesses() {
int list_length = guesses.size();
System.out.print("Your guesses: ");
for (int counter = 0; counter < list_length; counter++)
{
System.out.print(guesses.get(counter) + " ");
}
System.out.println();
}
boolean checkLastGuess()
{
int numToTest = guesses.get(guesses.size()-1);
if (numToTest == numToGuess)
{
return true;
}
else
{
return false;
}
}
}
您没有正确初始化arraylist。改变
ArrayList guesses = new ArrayList();
到
ArrayList guesses=new ArrayList();
ArrayList是通用的(
ArrayList
),因为它们要求在其构造中指定一个对象,以便您知道ArrayList中的内容。将猜测作为一个ArrayList
错误发生在哪一行?错误发生在“int numtoest=guesses.get(guesses.size()-1);”
ArrayList guesses = new ArrayList();
ArrayList<Integer> guesses = new ArrayList<Integer>();