String predefined method doubt???

[Vishal Hegde]

public class SB
{
public static void main(String args[])
{
StringBuffer s1=new StringBuffer();
StringBuffer s2=new StringBuffer();
s1.insert(0,"Hello from Java");
s2.insert(0, s2);
System.out.println(s1);
System.out.println(s2);
}

}

s2 is displaying nothing not even null as it is not even referecing to any object ,why is this happening???

[salvin francis]

Answer seems to be posted here:
http://www.coderanch.com/t/473341/Java-General/java/with-string-predefined-method

Please note OP in both the cases

[Rob Spoor]

This problem is slightly different.

Vishal, what does s2 contain when you try to add it to itself? Also, please use code tags in the future.

[Campbell Ritchie]

And also, your thread title doesn't quite tell us what the question is about. StringBuffer, not String, please.

By the way: StringBuilder is usually more efficient in that sort of circumstances.