On Sat, Nov 13, 2010 at 4:33 PM, Shi Yu <[email protected]> wrote: > I agree with Steve. That's why I am still using 0.19.2 in my production. > > Shi > > On 2010-11-13 12:36, Steve Lewis wrote: >> >> Our group made a very poorly considered decision to build out cluster >> using >> Hadoop 0.21 >> We discovered that a number of programs written and running properly under >> 0.20.2 did not work >> under 0.21 >> >> The first issue is that Mapper.Context and Reducer.Context and many of >> their >> superclasses were >> converted from concrete classes to interfaces. This change, and I have >> never >> in 15 years of programming Java seen so major >> a change to well known public classes is guaranteed to break any code >> which >> subclasses these objects. >> >> While it is a far better decision to make these classes interface, the >> manner of the change and the fact that it is poorly >> documented shows extraordinary poor judgement on the part of the Hadoop >> developers >> >> http://lordjoesoftware.blogspot.com/ >> >> > > >
At times we have been frustrated by rapidly changing API's # 23 August, 2010: release 0.21.0 available # 26 February, 2010: release 0.20.2 available # 14 September, 2009: release 0.20.1 available # 23 July, 2009: release 0.19.2 available # 22 April, 2009: release 0.20.0 available By the standard major/minor/revision scheme 0.20.X->0.21.X is a minor release. However since hadoop has never had a major release you might consider 0.20->0.21 to be a "major" release. In any case, are you saying that in 15 years of coding you have never seen an API change between minor releases? I think that is quite common. It was also more then a year between 0.20.X and 0.21.X. Again common to expect a change in that time frame.
