Java Data Type - 如何使用for循环交换字符串字符

public class Main {
  public static void main(String args[]) {
    String name = "premkumarg";
    int len = name.length();
    char[] c = name.toCharArray();
    for (int i = 0; i < len - 1; i = i + 2) {
      char temp = c[i];
      c[i] = c[i + 1];
      c[i + 1] = temp;
    }

    System.out.println("Swapping string is: ");
    System.out.println(c);

  }
}