Re: Beginner doubt about access and methods

Mark Space <>
Sun, 20 May 2007 17:40:14 GMT
Jordi wrote:

These methods may only be used by classes in its package

I avoided using public methods or public variables for this class and
its subclasses to increase security.
Is this a good point, or not?

So far, so good. Although for instance variables I prefer private.

 > So when I write a class that extends the class Data, I must set those
 > variables with:
 > setData("blabla");

This I don't understand. Usually, an abstract class has abstract
methods. If all you are doing is setting instance variables, I think
you may need a regular class.

class MyData {
    private String someData;
    void setData( String s ) {
        someData = s;
    public static main( String [] args ) {
        MyData datum = new MyData();
        datum.setData( "blah" );

This is fine.

I saw some people do things like this but I don't know if I am doing
well. Most people used private variables but public methods.

Package private is fine, if that's what you want. I think it's a good
way to add structure and encapsulation to a package, while preventing
classes outside the package from getting at classes which they
shouldn't. I do prefer private instance variables, since I think that's
also good encapsulation.

My only concern is that I don't see why the class needs to be abstract,
and I don't see why it needs to implement Serializable. (You don't do
anything with Serializable in your example.)

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