Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
1.4k views
in Technique[技术] by (71.8m points)

sorting - Grails mapping sort on multiple fields :: Groovy sort on multiple map entries

Stumped on this one. In Grails it seems one cannot define a default sort on multiple columns in domain mapping a la static mapping = { sort 'prop1 desc, prop2 asc' }, or { sort([prop1:'desc', prop2:'asc']) }. Only first column gets sorted, lame.

Similarly, when trying to Groovy sort a Grails findAllBy query on multiple columns, the second sort overrides the first.

def list = [[rowNum:2,position:3],[rowNum:1,position:2],[rowNum:3,position:1]]

list.sort{it.rowNum}.sort{it.position}

Obviously missing the boat on the latter case, the groovy sort. I have seen postings re: implementing comparable, but looking for something more concise if possible.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

Here is a Groovy solution. Still essentially implementing a Comparator though.

list.sort { map1, map2 -> map1.rowNum <=> map2.rowNum ?: map1.position <=> map2.position }

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...