How to check if element in groovy array hash collection list

Question

How do I figure out if an array contains an element   I thought there might be something like  1  2  3  includes 1  which would evaluate as true

User · Answer

IMPORTANT Gotcha for using  contains   on a Collection of Objects  such as Domains   If the Domain declaration contains a EqualsAndHashCode  or some other equals   implementation to determine if those Ojbects are equal  and you ve set it like this     import groovy transform EqualsAndHashCode  EqualsAndHashCode includes    settingNameId  value     then the  contains myObjectToCompareTo  will evaluate the data in myObjectToCompareTo with the data for each Object instance in the Collection  So  if your equals method isn t up to snuff  as mine was not  you might see unexpected results

User · Answer

contains   is the best method for lists  but for maps you will need to use  containsKey   or  containsValue     a 1 b 2 c 3  containsValue 3   a 1 b 2 c 3  containsKey  a

User · Answer

def fruitBag     orange   banana   coconut   def fruit   fruitBag collect item - gt  item contains  n      I did it like this so it works if someone is looking for it

User · Answer

For lists  use contains    1 2 3  contains 1     true

User · Answer

You can use Membership operator   def list     Grace   Rob   Emmy   assert   Emmy  in list      Membership operator Groovy

User · Answer

You can also use matches with regular expression like this  boolean bool   List matches  quot   i   SOME STRING HERE   quot

User · Answer

Some syntax sugar  1 in  1 2 3

User · Answer

If you really want your includes method on an ArrayList  just add it   ArrayList metaClass includes     i - gt  i in delegate

[arrays] How to check if element in groovy array/hash/collection/list?

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