Transform and filter a Java Map with streams

Question

I have a Java Map that I\'d like to transform and filter. As a trivial example, suppose I want to convert all values to Integers then remove the odd entries.

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Answer 1

Guava's your friend:

Map output = Maps.filterValues(Maps.transformValues(input, Integer::valueOf), i -> i % 2 == 0);

Keep in mind that output is a transformed, filtered view of input. You'll need to make a copy if you want to operate on them independently.