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In the last lesson VSA how setters and getters can be used to prevent direct access of of us.

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But it's not just variables.

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We also want to be careful about what methods and classes we are exposed to external code that is there

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can be tight coupling to even methods and classes.

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So we will not look at another effective July time that gives some more advice on how we can go about

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hiding information.

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The item is item 13 and it says minimize the accessibility of classes and members.

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Let's review what it has to say and it's going to be a sharp lesson when it comes to designing class

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members here is a general solution from the item just carefully design a minimal public API of your

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class so once you have an idea of the variables on matters that go into your class just carefully look

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at all the class members and see which of them will really be needed by the clangor and just make them

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public all that how many members should be made private.

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Only if an class in the same package really needs access to a private member then you would convert

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it to the default access and same holds for converting something into public member.

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Now if you find yourself doing such conversions often then you may want to re-examine your design probably

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structuring your classes in a different way.

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Could be a better solution.

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Come into classes or interfaces vino that they can hire only public publico default access lever's surfer

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class or interface can have default as accessible then liquored have default access level because once

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it is public you would be obligated to support it for whatever.

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So basically give the client code access to only what they need.

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Match within your package if a class is used by only one other class then consider making that class

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a private master class within the class that uses it.

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Mr. Crossus will be introduced much later but it is simply a class that an underclass like in the strict

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follow up it simply exists to serve its enclosing class so that's about information hiding.

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So we software design principles that use access modifiers to achieve information hiding information

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hearting helps in building well-designed design software which then loosely coupled components as you

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can see the principles are pretty straightforward.

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Generally I think double uppers do use accessor methods for class members.

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However when it comes to classes they don't follow the advice that we see here.

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They usually make the classes public all the time.

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It may not be an issue at all if your code is never used outside your company but if you're writing

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code that will be used by public or your partners then you must follow the advice given in this lesson

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just know that this advice comes from Joshua ablock who has written tons of July API called on so it

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would serve us well if you take his advice seriously Also one last comment I would like to make is sometimes

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people refer to encapsulation as information hiding in our case they're introduced us separate concepts

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and that is very widely acceptable as we look at them so just want to highlight that sometimes you may

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come across people using the term encapsulation for information hiding.

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But you know what that mean in fact the supplementary notes includes a link to a great article on this

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topic and you can check it out in your free time.

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And that's about it.

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Thank you