Is there any good use for a default Java class (i.e. non-public, non-abstract, non-final, subclass of Object) -

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i've been programming in c , c++ few years , taking java classes first time. i've come across chapter on java classes , curious default declaration java class:

class myclass {

//vars , methods

}

this compiles i'm told, have practical usage, such in particular design patterns or applications?

if matters, java 6. old, know, project @ work built on java6 , that's motivating me learn this.

the default access in java package private. means class visible other classes in same package.

it useful, example, if write library , want prevent users of library directly using internal classes not part of api. allows change internal classes in later versions without having worry backward compatibility.


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