Java String方法将字符串转换为字符，然后显示具有指定索引的字符

我试图编写一个关于字符串方法的代码，该方法接受字符串并返回getChars的值。索引应该是用户的输入。字符串应转换为将用作目标的字符数组。然而，我有一些令人困惑的错误

有什么帮助吗？ 这是代码/

    import java.util.*;
    public class Exercise5 {
    public static void main(String[] args) {
        //Stay Calm and Be Cool!
        Scanner a = new Scanner(System.in);
        String string = new String();

        System.out.print("Enter any String: ");
        string = a.nextLine();

        System.out.print("Enter source begin index: ");
        int begin = a.nextInt();

        System.out.print("Enter source end index: ");
        int end = a.nextInt();

        System.out.print("Enter destination index: ");
        int dest = a.nextInt();

        char[] sample = string.toCharArray();
        System.out.println("The value extracted from " + string + " with indexes "+ begin + " to "+ end + " is: " + 
                string.getChars(begin, end, sample, dest));
    }

}

错误：不允许使用void--如何消除该问题？

StringgetChars不返回任何值，它将结果写入dest参数：

final int length = end - begin;
char[] sample = new char[length];
string.getChars(begin, end, sample, dest);
System.out.println("The value extracted from " + string + " with indexes "+ begin + " to "+ end + " is: " + sample);

---

What char[]sample=string.toCharArraysample；应该怎么办？您正在尝试调用哪个方法？你能链接它的JavaDoc吗，因为我没有看到任何接受char[]的toCharArray。对不起，这个示例不能在那个paradensis中。。。