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    <h2>The short answer:</h2> <p>1) Data hiding can be achieved without encapsulation, an example of this would be a private constant in a class, and that constant is not returned by any 'getter'.</p> <p>2) Applying an access modifier <strong>might</strong> be data hiding and encapsulation. You can achieve encapsulation but not data hiding, when you expose the data, but only to be modified by getters and setters.</p> <h2>And the long answer:</h2> <p>Data hiding and encapsulation are quite different things, but related concepts. Data hiding is about not leaking the implementation details any user of your class, while encapsulation is preventing unexpected changes on the data.</p> <p>The best explanation I've found of this is in the book `Growing Object Oriented Systems Guided by Tests" (page 49)</p> <p>What the authors say is that encapsulation is almost always a good thing, but data hiding can be in the wrong place, and they give the following example:</p> <ul> <li>Encapsulate the data structure for the cache in the Loader class</li> <li>Encapsulate the name of the application's log file in the PrivacyPolicy class</li> </ul> <p>Both of the above sound sensible, until we put them from the point of view of data hiding</p> <ul> <li>Hide the data structure for the cache in the Loader class</li> <li>Hide the name of the application's log file in the PrivacyPolicy class</li> </ul> <p>In the example of the cache, it makes sense to hide it. But regarding the application log file name it doesn't make sense to hide it.</p>
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    1. POdata hiding is encapsulation, but not all encapsulation is data hiding
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    1. CO+1 for `Data hiding is about not leaking the implementation details any user of your class, while encapsulation is preventing unexpected changes on the data.`
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    2. COAwesome answer , very clear.Now I just want to know 1 thing and then ill accept your answer.1) From the line `encapsulation is preventing unexpected changes on the data` it means by applying getter setters we can eaisly achieve the encapsulation.Right?(If you have any other example then please share as well).2) From the line `Data hiding is about not leaking the implementation details any user of your class` It means not only from the Encapsulation , but also from the abstraction we can achieve the data hiding? (Also if you have any other example of data hiding then please share)
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    3. COif **Data hiding is about not leaking the implementation details** then what is diffrence between data hiding and abstraction? Are they same?
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