java - Whats the difference between vs -



java - Whats the difference between <[]> vs <null> -

<[]> vs <null>

the first empty set containing no objects. can created code:

set<node> expected =new hashset<>();

the sec set containing 1 null element. if not, can null have type set?

not sure how code sec item.

<[]> means object include no elements. null not element. after u phone call construction method new hashset<>();, set point real memory. null point nowhere.

java collections junit set

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