package J20250715.stringbuider; /** * @author WanJl * @version 1.0 * @title Demo02 * @description * @create 2025/7/15 */ public class Demo02 { public static void main(String[] args) { //创建StringBuilder可变字符串对象--无参数 StringBuilder sb=new StringBuilder(); System.out.println("sb:"+sb); System.out.println("sb.length() :"+sb.length()); //创建StringBuilder可变字符串对象--有参数 StringBuilder sb1=new StringBuilder("hello world"); System.out.println("sb1:"+sb1); System.out.println("sb1.length() :"+sb1.length()); //调用StringBuilder追加字符串的方法 append(任意类型); sb.append("今天"); sb.append("是个"); sb.append("好天气"); System.out.println("sb:"+sb); System.out.println("sb.length() :"+sb.length()); //调用方法实现字符串反转 sb.reverse(); System.out.println("字符串反转:"+sb); } }