java - Notation of the Dynamic Querying Associations -

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in latest documentation of grails, can read:

querying associations. associations can used within queries:

def author = author.findbyname("stephen king")  def books = author ? book.findallbyauthor(author) : []

i'd know meaning of ? , : []

shorthand if statement in groovy (and java, see first comment).

def books = author ? book.findallbyauthor(author) : []

is equivalent of:

def books if (author) {     books = book.findallbyauthor(author) } else {     books = [] }

see elvis operator (groovy only, not java) here.


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