How to create a Function2 instance using lambdas in Java? -


i trying implement lambda function2 in java:

javapairrdd<string, integer> reducedcounts = counts.reducebykey(new function2<integer, integer, integer>() {     @override     public integer call(final integer value0, final integer value1) {         return integer.valueof(value0.intvalue() + value1.intvalue());     } });

the above sample, how change lamb8 format? wanna define separate function

function2<...> f2 = lambda; counts.reducebykey(f2);

you can go method reference easiest option in case:

function2<integer, integer, integer> f2 = integer::sum; counts.reducebykey(f2)

which equal to:

function2<integer, integer, integer> f2 = (i1, i1) -> i1 + i2; counts.reducebykey(f2)

also, such simplification possible because perform lot of unnecessary boxing/unboxing in order calculate sum of 2 integers.


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