import java.text.*;

   public class Gxjun

  {

     public static void main(String atgs[])

     {

        StringBuffer str= new StringBuffer();

        str.append("大家好");

        System.out.println("str:"+str);

        System.out.println("length:"+str.length());

        System.out.println("capacity:"+str.capacity());

        str.setCharAt(0,'w');

        str.setCharAt(1,'e');

        System.out.println(str);

        str.insert(2, "are all");

        System.out.println(str);

        int index=str.indexOf("好");

        str.replace(index, str.length(),"right");

        System.out.println(str);

     }

  }