Hi Robin, Thanks for the suggestion. I did find such an example in Hadoop The definitive guide book. However I am not total confused.
The book extends UDAF instead of AbstractGenericUDAFResolver. Which one is recommended ? Also the example in the book uses DoubleWritable as a return type for the "terminate" function. However, I will be returning an arraylist of double. Do I always need to written objects that are derived from WritableComponents. Ritesh On Jul 29, 2013, at 4:15 PM, Robin Morris wrote: > I believe a map will be passed correctly from the terminatePartial to the > merge functions. But it seems a bit of overkill. > > Why not define a class within your UDAF which has 4 public data members, > and return instances of that class from terminatePartial()? > > Robin > > > On 7/29/13 3:19 PM, "Ritesh Agrawal" <[email protected]> wrote: > >> Hi all, >> >> I am writing my first UDAF. In my terminatePartial() function, I need to >> store different data having different data types. Below is a list of >> items that I need to store >> 1. C1 : list of doubles >> 2. C2: list of doubles >> 3. C3: double >> 4. Show: list of strings >> >> >> I am wondering can I use simple HashMap and store these different objects >> into it. Will it automatically serialize or will I need to write my own >> serializiable method. Also is there any example of a UDAF that shows how >> to use map type structure for storing partial results. >> >> Thanks >> >> Ritesh >
