StringBuffer 클래스

import java.util.*;

public class Main {
	
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scanner=new Scanner(System.in);
		
		StringBuffer sb=new StringBuffer("This");
		
		sb.append(" is pencil");
		System.out.println(sb);
		
		sb.insert(7, " my");
		System.out.println(sb);
		
		sb.replace(8, 10, "your");
		System.out.println(sb);
		
		sb.delete(8, 13);
		System.out.println(sb);
		
		sb.setLength(4);
		System.out.println(sb);
		
		scanner.close();
	}

}