How to judge a string is UUID type? [duplicate]

Handle the exception and do something in that case. For example :

try{
    UUID uuid = UUID.fromString(someUUID);
    //do something
} catch (IllegalArgumentException exception){
    //handle the case where string is not valid UUID 
}

You should use regex to verify it e.g.:

^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$

test it with e.g.g 01234567-9ABC-DEF0-1234-56789ABCDEF0

or with brackets

^\{?[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}‌​\}?$