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    <p>Unless you perform some kind of validation when setting the values (i.e. balance is not negative), use <code>public</code> if possible. </p> <p>Creating both a getter and a setter for an attribute that merely return or assign a value, without additional logic actually exposes your attribute as <code>public</code> and provide unnecessary clutter to the code (in terms of readability). Using public attributes directly makes the code cleaner.</p> <p><strong>Example 1:</strong></p> <p>*You want to allow an account to only have positive balance. You will have to perform a check to see if you are assigning it a negative value EVERY time you assign it a value. </p> <p>The best place to do this would be in a setter method. This gets you rid of the trouble of having to put a lot of <code>if(newBalance &lt; 0)</code> checks all over the place. </p> <p>To enforce the fact that you want only positive balance values, you make the attribute <code>private</code>. This restricts the programmers who might want to assign a negative value to a <code>balance</code> attribute(*). In order to make the value held within the balance attribute accessible again, you would need to add a getter for the private value. </p> <p>You now have "some kind" of a <code>public</code> attribute on which you enforce restrictions (not being able to be set as negative).</p> <p><strong>Example 2:</strong></p> <p>You want to take notes on every account. You will have a <code>String notes;</code> attribute in your class. </p> <p>If there are not restrictions you want to enforce, the best here is to use <code>public</code> modifier for it.</p> <p>Consider which of the following pieces of code is cleaner:</p> <pre><code>accountA.setNotes(accountB.getNotes()); </code></pre> <p>or</p> <pre><code>accountA.notes = accountB.notes; </code></pre> <p>They both copy <code>notes</code> from one account to the other, but the latter is easier to read.</p>
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    1. POPublic vs Private
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    1. USlucian.pantelimon
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    1. COyour fields should never be public unless absolutely necessary
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      1. USJeff Hawthorne
    2. COagreed - this goes against the concept of OO.
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      1. USBoris the Spider
    3. CO-1 - The idea using of accessors and mutators is to allow you to change the implementation later without needing to update a bunch of other code. For instance, I could change a simple setter to include validation. Or I could change a getter to not return the private field anymore and instead perform a calculation. I would say the "clutter" is worth it, especially since most IDEs will generate this code for you anyway.
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      1. USJesse Webb
 

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