老铁们，能具体解释一下吗？
import java.util.Arrays;
public class Demo{
private String str="1234";
private char[] chars={'a','b','c'};
public static void main(String[] args){
Demo demo=new Demo();
System.out.println(demo.str+" "+ Arrays.toString(demo.chars));
change(demo.str,demo.chars);
System.out.println(demo.str+" "+ Arrays.toString(demo.chars));
}
public static void change(String str,char[] chars){
str="5678";
chars[2]='b';
}
}
