hadoop - MapReduce output as ArrayList -

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how call map reduce method in normal java project , possible return reducer output arraylist / hashmap instead of flat file, , how access mapreduce method jboss appserver.

here sample program uses multipleoutput 

    public void reduce(text key, iterator<intwritable> values,             outputcollector<text, intwritable> output, reporter reporter)             throws ioexception {         int total = 0;           (; values.hasnext();) {             total += values.next().get();             mos.getcollector("text", reporter).collect(key,                     new intwritable(total));             mos.getcollector("seq", reporter).collect(key,                     new intwritable(total));         }      }

you need create multipleoutputs instance in configure method.

    private multipleoutputs mos;      @override     public void configure(jobconf job) {          mos = new multipleoutputs(job);     }

in driver class need tell inputformats want use. below generate output in text , sequence file formats.

// defines additional single text based output 'text' job     multipleoutputs.addnamedoutput(conf, "text", textoutputformat.class,             text.class, intwritable.class);      // defines additional sequence-file based output 'sequence' job     multipleoutputs.addnamedoutput(conf, "seq",             sequencefileoutputformat.class, text.class, intwritable.class);

but understood question, want access mapreduce output code. may download output file using hdfs api. better put data in hive table , access using jdbc.


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