> > If CharSequence is mutable and thread-safe, I would expect toString() > implementation to provide the atomic snapshot (e.g. do the > synchronization). Therefore, I find Sherman's argument interesting.
That's my point about "it ought to be up to the caller" -- they're in a position to make this call, but String.contains() is playing defensive because it has no clue of the context. On Fri, Mar 20, 2015 at 11:55 AM, Aleksey Shipilev < aleksey.shipi...@oracle.com> wrote: > If CharSequence is mutable and thread-safe, I would expect toString() > implementation to provide the atomic snapshot (e.g. do the > synchronization). Therefore, I find Sherman's argument interesting. > > On the other hand, we don't seem to be having any details/requirements > for contains(CharSequence) w.r.t. it's own argument. What if > String.contains pulls the values one charAt at a time? The concurrency > requirements are not enforceable in CharSequence alone then, unless you > call the supposed-to-be-atomic toString() first. > > -Aleksey. > > On 03/20/2015 06:48 PM, Vitaly Davidovich wrote: > > Yes, but that ought to be for the caller to decide. Also, although the > > resulting String is immutable, toString() itself may observe mutation. > > > > On Fri, Mar 20, 2015 at 11:40 AM, Xueming Shen <xueming.s...@oracle.com> > > wrote: > > > >> On 03/20/2015 02:34 AM, Tomasz Kowalczewski wrote: > >> > >>> Hello! > >>> > >>> Current implementation of String.contains that accepts CharSequence > calls > >>> toString on it and passes resulting string to indexOf(String). This IMO > >>> defeats the purpose of using CharSequences (that is to have a mutable > >>> character buffer and not allocate unnecessary objects). > >>> > >>> > >> It is arguable that cs.toString() may serve the purpose of taking a > >> snapshot of an otherwise > >> "mutable" character buffer? > >> > >> -Sherman > >> > >> > >> Is changing this a desirable development? It seems pretty > straightforward > >>> to port indexOf(String) to use CharSequence. > >>> > >>> If all you need is patch then I can work on it (I have signed OCA) just > >>> wanted to make sure it is not a futile work. > >>> > >>> > >> > >> > > >
