StringBuilder书写出现报错

Question

Java中StringBuilder书写出现报错，集中在length和字符串上

public class StringBuilder {
    public static void main(String[] args) {
        StringBuilder sb=new StringBuilder();
        System.out.println("sb:"+sb);
        System.out.println("sb.length():" + sb.length());//此处会报错

        StringBuilder sb2= new StringBuilder("hello");//"hello"也会报错
        System.out.println("sb2:"+sb2);
        System.out.println("sb2.length:"+sb2.length());//此处也会报错
    }
}

Answer 1

你的类名有问题，你的类名不能为StringBuilder，重名了！！！！