Doubt of String Buffer for Vicken Karaoghlanian & others

[Vishy Karl]

hi friends, (
posted August 28, 2003 03:34 AM by Vicken Karaoghlanian )
this thread was posted by Vicken , what is the solution to this problem ?

class Test {
   public static void main(String args[]) {
      StringBuffer ss = new StringBuffer("1234567890123456"); // line 1
      StringBuffer s = new StringBuffer("12345");  // line 2
      s.append(ss);  // line 3
      System.out.println(s.capacity());  // line 4
   }
}

1) on line 2, a string buffer (s) of capacity 16 + 5 = 21 is created.
2) on line 3, we appended ss to s making 16 + 5 = 21, which fits perfectly in s, making the output on line 4 equals to 21.
my question is: if we add another character to ss

StringBuffer ss = new StringBuffer("12345678901234567");

the output (capcity) of s becomes 44 !!! isn't suppose that the capacity increases by one, hence becoming 22??
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[ Jess adjusted the code and added UBB [code] tags to make it readable and to preserve the whitespace, check 'em out! ]
[ October 09, 2003: Message edited by: Jessica Sant ]

[Jessica Sant]

check out the API -- http://java.sun.com/j2se/1.4.1/docs/api/java/lang/StringBuffer.html
When you call StringBuffer.append() it firsts calls StringBuffer.ensureCapacity()

public void ensureCapacity(int�minimumCapacity)
Ensures that the capacity of the buffer is at least equal to the specified minimum. If the current capacity of this string buffer is less than the argument, then a new internal buffer is allocated with greater capacity. The new capacity is the larger of:
* The minimumCapacity argument.
* Twice the old capacity, plus 2.
If the minimumCapacity argument is nonpositive, this method takes no action and simply returns