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POOverriding vs Hiding Java - Confused
 

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    <p>I'm confused on how Overriding differs from Hiding in Java. Can anyone provide more details on how these differ? I read the <a href="http://docs.oracle.com/javase/tutorial/java/IandI/override.html" rel="nofollow noreferrer">Java Tutorial</a> but the sample code still left me confused.</p> <p>To be more clear, I understand Overriding well. My issue is that I don't see that hiding is any different except for the fact that one is at the instance level while the other is at the class level.</p> <p>Looking at the Java tutorial code:</p> <pre><code>public class Animal { public static void testClassMethod() { System.out.println("Class" + " method in Animal."); } public void testInstanceMethod() { System.out.println("Instance " + " method in Animal."); } } </code></pre> <p>Then we have a subclass cat:</p> <pre><code>public class Cat extends Animal { public static void testClassMethod() { System.out.println("The class method" + " in Cat."); } public void testInstanceMethod() { System.out.println("The instance method" + " in Cat."); } public static void main(String[] args) { Cat myCat = new Cat(); Animal myAnimal = myCat; Animal.testClassMethod(); myAnimal.testInstanceMethod(); } } </code></pre> <p>Then they say:</p> <blockquote> <p>The output from this program is as follows:</p> <p>Class method in Animal.</p> <p>The instance method in Cat.</p> </blockquote> <p>To me, the fact that calling a class method testClassMethod() directly from the Animal class, executes the method in Animal class is pretty obvious, nothing special there. Then they call the testInstanceMethod() from a reference to myCat, so again pretty obvious that the method executed then is the one in the instance of Cat.</p> <p>From what I see what the call hiding behaves just like overriding, so why make that distinction. If I run this code using the classes above:</p> <pre><code>Cat.testClassMethod(); </code></pre> <p>I'll get: <em>The class method in Cat.</em> But if I remove the testClassMethod() from Cat, then I'll get: <em>The class method in Animal.</em></p> <p>Which shows me that writing a static method, with the same signature as in the parent, in a subclass pretty much does an override.</p> <p>Hopefully I'm making clear my where I'm confused and someone can shed some light. Thanks very much in advance!</p>
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