Why is StringBuilder.toString() returning new String instances for empty strings ?

[Remi Forax]

On 02/28/2013 09:07 AM, Volker Simonis wrote:
> Probably because the API-Spec
> (http://docs.oracle.com/javase/7/docs/api/java/lang/StringBuilder.html#toString%28%29)
> says "..A new String object is allocated and initialized to contain
> the character sequence currently represented by this object..".
>
> Regards,
> Volker

Also, this kind of short circuit 'if' in a heavily used code like 
StringBuilder.toString() can have bad interaction with the way the VM 
optimize/deoptimize. See this thread for more information.
http://mail.openjdk.java.net/pipermail/core-libs-dev/2012-May/010295.html

Rémi

>
> On Thu, Feb 28, 2013 at 8:47 AM, Jan Ohlsen <jan.t.ohlsen at gmail.com> wrote:
>> System.out.println( new StringBuilder().toString() == "" );
>> -> "false"
>>
>>
>> Any reason for not returning the "" instance?
>>
>>
>>      public String toString() {
>>          return new String(value, 0, count);
>>      }
>>
>> -->
>>
>>      public String toString() {
>>          return (count > 0) ? new String(value, 0, count) : "";
>>      }
>>
>> ?