JavaSE StringBuffer

public class StringBufferTest {
    public static void main(String[] args) {
        StringBuffer sb = new StringBuffer("张三");
        // StringBuilder sb = new StringBuilder("张三");
        // append 拼接
        sb.append("李四");
        // 删除一部分字符串
        sb.delete(sb.indexOf("三"), sb.indexOf("四"));
        // 插入
        sb.insert(1, "abc");
        // 查询
        int i = sb.indexOf("张");
        // 修改
        sb.replace(1, 2, "cba");
        // 反转
        sb.reverse();
        System.out.println(i);
        System.out.println(sb);

    }

}