Details
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New Feature
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Status: Open
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P3
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Resolution: Unresolved
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None
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None
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None
Description
GroupByKey is useful, but it is difficult to express complex grouping conditions.
I propose the development of the function to group if there is a common term in even one of multiple keys.
Like this....
usage
List io = Arrays.asList( KV.of(new MultiKey("A","C", "E"),"0"), KV.of(new MultiKey("A","D", "F"),"1"), KV.of(new MultiKey("B","D", "G"),"2"), KV.of(new MultiKey("H","J", "L"),"3"), KV.of(new MultiKey("I","K", "L"),"4"), KV.of(new MultiKey("M","C", "O"),"5"), KV.of(new MultiKey(null,null, "O"),"6"), KV.of(new MultiKey(null,null, null),"7") ); p.apply(Create.of(io)) .apply(GroupByMultiKey.create(3)) .apply(new DebugPrintln());
out put this
[KV{["A","C","E"],"0"},KV{["A","D","F"],"1"},KV{["B","D","G"],"2"},KV{["M","C","O"],"5"},KV{[null,null,"O"],"6"}]
[KV{["H","J","L"],"3"},KV{["I","K","L"],"4"}]
[KV{[null,null,null],"7"}]