我正在制作一个 java 程序来检查用户的输入，看看它是否是回文。我的代码在下面，但在：
if(isPalindrome() = true)
System.out.println("You typed a palindrome!");
部分我收到错误消息“赋值的左侧必须是变量”。不是变量吗？我能做些什么来解决它？任何建议表示赞赏！
public class PalindromeChecker
{
public static void main(String [] args)
{
String answer;
while(answer.equalsIgnoreCase("y"))
{
System.out.println("Please enter a String of characters. I will check to see if");
System.out.println("what you typed is a palindrome.");
Scanner keys = new Scanner(System.in);
String string = keys.nextLine();
if(isPalindrome() = true)
System.out.println("You typed a palindrome!");
else
System.out.println("That is not a palindrome.");
System.out.print("Check another string? Y/N: ");
answer = keys.next();
}
}
public static boolean isPalindome(String string)
{
if(string.length() <= 0)
System.out.println("Not enough characters to check.");
string = string.toUpperCase();
return isPalindrome(string,0,string.length()-1);
}
private static boolean isPalindrome(String string, int last, int first)
{
if(last <= first)
return true;
if(string.charAt(first) < 'A' || (string.charAt(first) > 'Z'))
return isPalindrome(string,first + 1, last);
if(string.charAt(last) < 'A' || (string.charAt(last) > 'Z'))
return isPalindrome(string,first, last - 1);
if(string.charAt(first) != string.charAt(last))
return false;
return isPalindrome(string,first + 1, last - 1);
}
}