Java UDF and incompatible schema

[Sameer Tilak]

Hi everyone,

I have written my custom parser and since my files are sm,all I am using 
sequence file for efficiency. Each file in the equence file has info about one 
user and I am parsing that file and I would like to get a bag of tuples for 
every user/file/.  In my Parser class I have implemented exec function that 
will be called for each file/user.  I then gather the info and package it as 
tuples. Each user will generate multiple tuples sine the file is quite rich and 
complex. Is it correct to assume that the  the relation AU will contact one bag 
per user? 

When I execute the following script, I get the following error. Any help with 
this would be great!
ERROR 1031: Incompatable field schema: declared is 
"bag_0:bag{:tuple(id:int,class:chararray,name:chararray,begin:int,end:int,probone:chararray,probtwo:chararray)}",
 infered is ":Unknown"


Java UDF code snippet

PopulateBag
{

                for (MyItems item : items)
                {


                    Tuple output = TupleFactory.getInstance().newTuple(7);


                    output.set(0, item.getId());

                    output.set(1, item.getClass());

                    output.set(2,item.getName());
                    
                    output.set(3,item.Begin());

                    output.set(4,item.End());

                    output.set(5,item.Probabilityone());

                    output.set(6,item.Probtwo());

                    m_defaultDataBag.add(output);


                }
 }
 
     public DefaultDataBag exec(Tuple input) throws IOException {
     
     try
           {

               this.ParseFile((String)input.get(0));
               this.PopulateBag();
           return m_defaultDataBag;
           } catch (Exception e) {
           System.err.println("Failed to process th i/p \n");
           return null;
       }
}


Pig Script

REGISTER 
/users/p529444/software/pig-0.11.1/contrib/piggybank/java/piggybank.jar;
REGISTER /users/p529444/software/pig-0.11.1/parser.jar

DEFINE SequenceFileLoader org.apache.pig.piggybank.storage.SequenceFileLoader();

A = LOAD '/scratch/file.seq' USING SequenceFileLoader AS (key: chararray, 
value: chararray);
DESCRIBE A;
STORE A into '/scratch/A';

AU = FOREACH A GENERATE parser.Parser(key) AS {(id: int, class: chararray, 
name: chararray, begin: int, end: int, probone: chararray, probtwo: chararray)};