java - Will inheritance break encapsulation? -

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let's have csv file , create class called csvfile extends java.io.file. class can parse csv file , return data how many columns in file. can used functions takes java.io.file input. fileutils.copyfile(file from, file to).

my colleague thinks expose inheritance. idea wrap java.io.file holding in private property, instead of inheriting it. think exposing public method/property file breaks encapsulation, take benefit since functions in java.io.file free.

what think?

i rather agree colleague: inheriting java.util.file expose methods not applicable csvfile objects, such list(), listfiles(), setexecutable(), , on.

making java.util.file property behind getter sounds better choice: not reveal irrelevant operations users of class, , lets inherit base class of choice.


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