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Everything
we do in Java is part of a class
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This
means that none of our functions can be “global” like they can be in
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C or
C++
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Classes
in Java specify types, as they do in C++ and allow us to
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create
abstractions
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Classes
must be specified as public, or not.
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Only
public classes are available for the outside world to create objects of
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If
the keyword public doesn’t precede a class, then it is “friendly” and
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only
classes from within this file or package (a group of files) can create
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objects
Every package (or file to begin with) has a public class
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Inside
of a class, Java supports public, protected, and private
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access
(or nothing – which means “friendly” access)
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But
unlike C++, it requires that they be specified in front of each member
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rather
than specifying categories!
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This
means that everything has some kind of access specified for it.
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