Why are the types different in Java variable declarations? -


this question has answer here:

what purpose of specifying different types on left , right side in java variable declarations?

for example, code standard:

list<string> l = new arraylist<>();

why don't:

arraylist<string> l = new arraylist<>();

or

object l = new arraylist<>(); // silly example shows 2 extremes

  • this list<string> l = new arraylist<>(); allows instantiate types of list, arraylist or linkedlistof string. can use methods of list
  • arraylist<string> l = new arraylist<>(); can instantiate arraylist of string.
  • object l = new arraylist<>(); cannot use list methods.

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