run(Context context)
{
setup(context);
while (context.nextKeyValue())
{
reduce(context.getCurrentKey(), context.getCurrentValue(), context);
}
cleanup(context);
}
setup(Context context)
reduce(Writable key, Writable value, Context context)
cleanup(Context context)
{
setup(context);
while (context.nextKeyValue())
{
reduce(context.getCurrentKey(), context.getCurrentValue(), context);
}
cleanup(context);
}
setup(Context context)
reduce(Writable key, Writable value, Context context)
cleanup(Context context)
The
Reducer class contains the run() method, which call its own setup() method only once, it also call a
map() method for each input and finally
calls it cleanup() method. We can override all above methods
in our code.
