Hi All, Any consensus on this ?
-Nitin On Tue, Aug 15, 2017 at 4:43 PM Gary Gregory <garydgreg...@gmail.com> wrote: > On Tue, Aug 15, 2017 at 5:32 PM, Gilles <gil...@harfang.homelinux.org> > wrote: > > > On Tue, 15 Aug 2017 22:52:32 +0000, nitin mahendru wrote: > > > >> On Tue, 15 Aug 2017 12:02:20 -0600, Gary Gregory wrote: > >> > >>> On Tue, Aug 15, 2017 at 10:38 AM, nitin mahendru > >>> <nitin.mahendr...@gmail.com > >>> > >>>> wrote: > >>>> > >>> > >>> How about having a state in the class itself which says that it's > >>>> mutable > >>>> or not. > >>>> If we call a setter on an immutable then it throws an exception. > >>>> By default the records are immutable and you need to make them > >>>> mutable > >>>> using a new API. > >>>> > >>> > >> A code example would be useful... > >> > >> > >> > >> > >> Below is the pull request I added. > >> https://github.com/apache/commons-csv/pull/21 > >> > > > > As I indicated in the previous message, this is functionally > > breaking. [I'm diverting this discussion over to the "dev" > > mailing list.] > > > > Saying that making record mutable is "breaking" is a bit unfair when we do > NOT document the mutability of the class in the first place. > > Gary > > > > > > The following should be an interesting read: > > http://markmail.org/message/6ytvmxvy2ndsfp7h > > > > > > Regards, > > Gilles > > > > > > > > > >> On Tue, Aug 15, 2017 at 11:17 AM Gilles <gil...@harfang.homelinux.org> > >> wrote: > >> > >> On Tue, 15 Aug 2017 12:02:20 -0600, Gary Gregory wrote: > >>> > On Tue, Aug 15, 2017 at 10:38 AM, nitin mahendru > >>> > <nitin.mahendr...@gmail.com > >>> >> wrote: > >>> > > >>> >> How about having a state in the class itself which says that it's > >>> >> mutable > >>> >> or not. > >>> >> If we call a setter on an immutable then it throws an exception. > >>> >> By default the records are immutable and you need to make them > >>> >> mutable > >>> >> using a new API. > >>> > >>> A code example would be useful... > >>> > >>> >> pros: Saves memory, Keeps the immutability benefits > >>> > >>> What kind of usage are you considering that a single transient > >>> record matters (as compared to the ~300 MB of the JVM itself...)? > >>> > >>> >> cons: people using "mutable" records need to be careful.(While > >>> >> threading > >>> >> maybe) > >>> >> > >>> > > >>> > Interesting idea! > >>> > > >>> > But I think I like the idea of a subclass better if we are going to > >>> > split > >>> > the behavior b/w mutable and immutable. > >>> > >>> Once you have a subclass that is able to modify the state of > >>> its parent, it's a mutable object. Period. > >>> There is no such thing as a "split". > >>> > >>> > > >>> > For my money and the KISS principle, I would just add the put method > >>> > in > >>> > CSVRecord. > >>> > >>> Then, any use that assumes immutability will be broken. > >>> > >>> > >>> Gilles > >>> > >>> > >>> > Gary > >>> > > >>> >> > >>> >> -Nitin > >>> >> > >>> >> > >>> >> > >>> >> > >>> >> On Tue, Aug 15, 2017 at 9:01 AM Gilles > >>> >> <gil...@harfang.homelinux.org> > >>> >> wrote: > >>> >> > >>> >> > On Tue, 15 Aug 2017 09:49:04 -0600, Gary Gregory wrote: > >>> >> > > That looks odd to me. What comes up for me is the use case where > >>> >> I > >>> >> > > want to > >>> >> > > ETL a file of 10,000,000 records and update, say, one column. If > >>> >> am > >>> >> > > forced > >>> >> > > to create a brand new record for every record read, that would > >>> >> be a > >>> >> > > shame. > >>> >> > > >>> >> > Why? > >>> >> > > >>> >> > > If I had a mutable record, I could just keep on updating it and > >>> >> using > >>> >> > > it to > >>> >> > > write each row. Read record, update it, write record. No extra > >>> >> memory > >>> >> > > needed. > >>> >> > > >>> >> > How is the size of 1 additional record going to matter compared to > >>> >> the > >>> >> > size of the whole program? > >>> >> > > >>> >> > > Either we can make the current record mutable (what's the harm?) > >>> >> or > >>> >> > > we can > >>> >> > > make the parser serve out mutable records based on a config > >>> >> setting. > >>> >> > > This > >>> >> > > could be a subclass of CSVRecord with the extra method I > >>> >> proposed. > >>> >> > > >>> >> > The harm is that you loose all the promises of immutability. > >>> >> > > >>> >> > Regards, > >>> >> > Gilles > >>> >> > > >>> >> > > > >>> >> > > Thoughts? > >>> >> > > > >>> >> > > Gary > >>> >> > > > >>> >> > > On Tue, Aug 15, 2017 at 8:33 AM, Gilles > >>> >> > > <gil...@harfang.homelinux.org> > >>> >> > > wrote: > >>> >> > > > >>> >> > >> On Tue, 15 Aug 2017 08:01:53 -0600, Gary Gregory wrote: > >>> >> > >> > >>> >> > >>> How does that work when you want to change more than one > >>> >> value? > >>> >> > >>> > >>> >> > >> > >>> >> > >> How about a "vararg" argument: > >>> >> > >> > >>> >> > >> /** > >>> >> > >> * @param orig Original to be copied. > >>> >> > >> * @param replace Fields to be replaced. > >>> >> > >> */ > >>> >> > >> public static CSVRecord createRecord(CSVRecord orig, > >>> >> > >> Pair<Integer, String> ... > >>> >> > >> replace) { > >>> >> > >> // ... > >>> >> > >> } > >>> >> > >> > >>> >> > >> > >>> >> > >> Gilles > >>> >> > >> > >>> >> > >> > >>> >> > >> > >>> >> > >>> Gary > >>> >> > >>> > >>> >> > >>> On Aug 15, 2017 00:17, "Benedikt Ritter" <brit...@apache.org> > >>> >> > >>> wrote: > >>> >> > >>> > >>> >> > >>> Hi, > >>> >> > >>>> > >>> >> > >>>> I very much like that CSVRecord is unmodifiable. So I’d > >>> >> suggest an > >>> >> > >>>> API, > >>> >> > >>>> that creates a new record instead of mutating the existing > >>> >> one: > >>> >> > >>>> > >>> >> > >>>> CSVRecord newRecord = myRecord.put(1, „value") > >>> >> > >>>> > >>> >> > >>>> I’m not sure about „put“ as a method name since it clashes > >>> >> with > >>> >> > >>>> java.util.Map#put, which is mutation based... > >>> >> > >>>> > >>> >> > >>>> Regards, > >>> >> > >>>> Benedikt > >>> >> > >>>> > >>> >> > >>>> > Am 15.08.2017 um 02:54 schrieb Gary Gregory > >>> >> > >>>> <garydgreg...@gmail.com>: > >>> >> > >>>> > > >>> >> > >>>> > Feel free to provide a PR on GitHub :-) > >>> >> > >>>> > > >>> >> > >>>> > Gary > >>> >> > >>>> > > >>> >> > >>>> > On Aug 14, 2017 15:29, "Gary Gregory" > >>> >> <garydgreg...@gmail.com> > >>> >> > >>>> wrote: > >>> >> > >>>> > > >>> >> > >>>> >> I think we've kept the design as YAGNI as possible... :-) > >>> >> > >>>> >> > >>> >> > >>>> >> Gary > >>> >> > >>>> >> > >>> >> > >>>> >> On Mon, Aug 14, 2017 at 3:25 PM, nitin mahendru < > >>> >> > >>>> >> nitin.mahendr...@gmail.com> wrote: > >>> >> > >>>> >> > >>> >> > >>>> >>> Yeah that also is OK. I though there is a reason to keep > >>> >> the > >>> >> > >>>> CSVRecord > >>> >> > >>>> >>> without setters. But maybe not! > >>> >> > >>>> >>> > >>> >> > >>>> >>> Nitin > >>> >> > >>>> >>> > >>> >> > >>>> >>> > >>> >> > >>>> >>> > >>> >> > >>>> >>> > >>> >> > >>>> >>> On Mon, Aug 14, 2017 at 2:22 PM Gary Gregory > >>> >> > >>>> <garydgreg...@gmail.com > >>> >> > >>>> > > >>> >> > >>>> >>> wrote: > >>> >> > >>>> >>> > >>> >> > >>>> >>>> Hi All: > >>> >> > >>>> >>>> > >>> >> > >>>> >>>> Should we consider adding put(int,Object) and > >>> >> put(String, > >>> >> > >>>> Object) to > >>> >> > >>>> the > >>> >> > >>>> >>>> current CSVRecord class? > >>> >> > >>>> >>>> > >>> >> > >>>> >>>> Gary > >>> >> > >>>> >>>> > >>> >> > >>>> >>>> On Mon, Aug 14, 2017 at 2:54 PM, nitin mahendru < > >>> >> > >>>> >>>> nitin.mahendr...@gmail.com> > >>> >> > >>>> >>>> wrote: > >>> >> > >>>> >>>> > >>> >> > >>>> >>>>> Hi Everyone, > >>> >> > >>>> >>>>> > >>> >> > >>>> >>>>> I recently pushed a change(pull request 20) to get the > >>> >> line > >>> >> > >>>> ending > >>> >> > >>>> >>> from > >>> >> > >>>> >>>> the > >>> >> > >>>> >>>>> parser. > >>> >> > >>>> >>>>> > >>> >> > >>>> >>>>> Now I want to push another change which I feel will > >>> >> also be > >>> >> > >>>> useful > >>> >> > >>>> for > >>> >> > >>>> >>>> the > >>> >> > >>>> >>>>> community. I want to add a CSVRecordMutable class which > >>> >> had > >>> >> > >>>> a > >>> >> > >>>> >>> constructor > >>> >> > >>>> >>>>> which accepts a CSVRecord object. So when we have a > >>> >> > >>>> CSVRecordMutable > >>> >> > >>>> >>>> object > >>> >> > >>>> >>>>> from it then we can edit individual columns using it. > >>> >> > >>>> >>>>> > >>> >> > >>>> >>>>> I would be using this to write back my edited CSV file. > >>> >> My > >>> >> > >>>> use case > >>> >> > >>>> >>> is to > >>> >> > >>>> >>>>> read a csv, mangle some columns, write back a new csv. > >>> >> > >>>> >>>>> > >>> >> > >>>> >>>>> I could have directly raised a pull request but I just > >>> >> > >>>> wanted to > >>> >> > >>>> float > >>> >> > >>>> >>>> the > >>> >> > >>>> >>>>> idea before and see the reaction. > >>> >> > >>>> >>>>> > >>> >> > >>>> >>>>> Thanks > >>> >> > >>>> >>>>> > >>> >> > >>>> >>>>> Nitin > >>> >> > >>>> >>>>> > >>> >> > >>>> >>>> > >>> >> > >>>> >>> > >>> >> > >>>> >> > >>> >> > >>>> >> > >>> >> > >>>> > >>> >> > >>>> > >>> >> > >>>> > >>> >> > >> > >>> > >>> > >>> > >>> --------------------------------------------------------------------- > >>> To unsubscribe, e-mail: user-unsubscr...@commons.apache.org > >>> For additional commands, e-mail: user-h...@commons.apache.org > >>> > >>> > >>> > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: user-unsubscr...@commons.apache.org > > For additional commands, e-mail: user-h...@commons.apache.org > > > > >
