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    <p>Don't use the <code>super</code> keyword to refer to other methods which aren't overridden. It makes it confusing for other developers trying to extend your classes.</p> <p>Let's look at some code which <em>does</em> use the <code>super</code> keyword in this way. Here we have 2 classes: <code>Dog</code> and <code>CleverDog</code>:</p> <pre><code>/* file Dog.java */ public static class Dog extends Animal { private String name; public Dog(String name) { this.name = name; } public String getName() { return name; } } /* file CleverDog.java */ public class CleverDog extends Dog { public CleverDog(String name) { super(name); } public void rollover() { System.out.println(super.getName()+" rolls over!"); } public void speak() { System.out.println(super.getName() + " speaks!"); } } </code></pre> <p>Now, imagine you are a new developer on the project, and you need some specific behavior for a clever dog who is on TV: that dog has to do all its tricks, but should go by its fictitious TV name. To accomplish this, you override the <code>getName(...)</code> method...</p> <pre><code>/* file DogOnTv.java */ public class DogOnTv extends CleverDog { String fictionalName; public DogOnTv(String realName, String fictionalName) { super(realName); fictionalName = fictionalName; } public String getName() { return fictionalName; } } </code></pre> <p>... and fall into a trap set by the original developer and their unusual use of the <code>super</code> keyword!</p> <p>The code above isn't going to work - because in the original <code>CleverDog</code> implementation, <code>getName()</code> is invoked using the <code>super</code> keyword. That means it always invokes <code>Dog.getName()</code> - irrelevant of any overriding. Consequently, when you use your new <code>DogOnTv</code> type...</p> <pre><code> System.out.println("Showcasing the Clever Dog!"); CleverDog showDog = new CleverDog("TugBoat"); showDog.rollover(); showDog.speak(); System.out.println("And now the Dog on TV!"); DogOnTv dogOnTv = new DogOnTv("Pal", "Lassie"); dogOnTv.rollover(); </code></pre> <p>... you get the wrong output:</p> <pre><code>Showcasing the Clever Dog! Tugboat rolls over! Tugboat speaks! And now the Dog on TV! Pal rolls over! Pal speaks! </code></pre> <p>This is not the usual expected behavior when you override a method, so you should avoid creating this kind of confusion using the <code>super</code> keyword where it doesn't belong.</p> <p>If, however, this is actually the behavior you want, use the <code>final</code> keyword instead - to clearly indicate that the method can't be overridden:</p> <pre><code>/* file CleverDog.java */ public class CleverDog extends Dog { public CleverDog(String name) { super(name); } public final String getName() { // final so it can't be overridden return super.getName(); } public void rollover() { System.out.println(this.getName()+" rolls over!"); // no `super` keyword } public void speak() { System.out.println(this.getName() + " speaks!"); // no `super` keyword } } </code></pre>
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