JAVA的SringBuilder的用法

public class Demo1 {
    public static void main(String[] args) {
        //StringBuilder的链式输出
        StringBuilder sb=new StringBuilder();
        sb.append("hello").append("kk").append(100);
        System.out.println(sb);
        //StringBuilder的反转
        sb.reverse();
        System.out.println(sb);
    }
}