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POJava: When I Instantiate a Subclass of an Abstract Class It Doesn't Recognize the Constructor of its Superclass
 

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  1. POJava: When I Instantiate a Subclass of an Abstract Class It Doesn't Recognize the Constructor of its Superclass
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    <p>I do not have very much Java experience but I see codes where there is an abstract class with a certain constructor and then a subclass of that abstract class without a constructor. Then when the subclass is instantiated it is constructed with its superclass constructor. Is that right?</p> <p>I have this abstract class:</p> <pre><code>public abstract class Tile{ public int x; public int y; public int z; protected Color color; protected float friction; protected float bounce; protected boolean liquid; public void Tile(int x, int y, int z){ this.x = x; this.y = y; this.z = z; init(); } abstract protected void init(); </code></pre> <p>And this subclass:</p> <pre><code>public class TestTile extends Tile{ protected void init(){ color = Color.RED; friction = 0.1f; bounce = 0.2f; liquid = false; } } </code></pre> <p>But when I instantiate a TestTile with this:</p> <pre><code>Tile tile = new TestTile(0, 0, 0); </code></pre> <p>the init() method never runs. All of the values defined inside it are null. I tried making what I though might be a redundant constructor in the subclass which just called super with the exact same parameters, but when I did that, even with super(x, y, z) the only statement inside it, it said this:</p> <blockquote> <p>TestTile.java:27: call to super must be first statement in constructor</p> </blockquote> <p>I want to make a bunch of subclasses of Tile which implement the properties of a Tile. If this is not the correct way to do that, what is a better way?</p> <p>I am using 32-bit Ubuntu Linux 11.04 if it has to do with anything.</p> <p>Thanks.</p>
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    1. COrelated http://stackoverflow.com/questions/260666/abstract-class-constructor-in-java look at first answer
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