String Buffer Trim in a java pgm

String Buffer Trim

public class JavaStringBufferTrimExample

{

public static void main(String[] args)

{

 StringBuffer sbf = new StringBuffer("   Hello World  !  ");

 String str = sbf.toString().trim();

System.out.println("StringBuffer trim: \"" + str +"\"");

System.out.println("\"" + trim(sbf) + "\"");

}

private static String trim(StringBuffer sbf)

{

int start, end;

for(start = 0; start < sbf.length(); start++)

{

if(sbf.charAt(start) != ' ')

break;

}

for(end = sbf.length(); end > start ; end--)

{

if(sbf.charAt(end-1) != ' ')

break;

}

return sbf.substring(start, end);

    }

}