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POJava - How to properly use Extends/Implements
 

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    <p>Okay so I am kind of confused about the uses of "extends" and "implements". Let me give a scenario, let's say I am making a simple tower defense game. So it was my understanding that if I made a class (TowerBase.java), I can fill it with variables and methods, such as; int hp, int damage, int attack(){ ... }, etc.... I figured I could then make many types of towers, lets say one is an archer tower, and inside TowerArcher.java I want to set TowerBase's variables to unique values for said tower. My understanding was that inside of TowerArcher if I extend TowerBase I have access to all of TowerBase's variables and methods since TowerBase is now the parent. So I tried this:</p> <pre><code>public class TowerBase { //Health (Range: 1-100) int hp; public int attack(int blah){ //Blah blah how the tower goes about attacking foe } </code></pre> <p>Then in the TowerArcher.java</p> <pre><code>public class TowerArcher extends TowerBase{ //Set TowerArcher's unique values hp = 10; } </code></pre> <p>Now somewhere in the game...</p> <pre><code>TowerArcher archer; archer.attack(blah); </code></pre> <p>Eclipse throws this syntax error in TowerArcher.java at "hp = 10;": VarableDeclaratorId expected after this token. Which I presume that it was saying it doesn't know what hp is. This confuses me since I thought it would know what hp was since it's in the parent class. I have found work-arounds but they don't seem as effective and even if they work they still leave me confused as to what extends and implements are really for. Basically what I am trying to find out here is; <br/> 1: What does extends do <br/> 2: How could I use extends in my program intuitively <br/> 3: What does implements do <br/> 4: How could I use implements in my program intuitively <br/> 5: What I should use in this scenario where I have many different objects (towers) doing nearly the same thing, perhaps TowerArcher TowerBunker TowerSnipernest TowerBarricade etc. <br/> <br/> I know I am asking for a lot but I couldn't find a good post on it so this could help others too :) <br/>P.S. If I am missing any needed information please let me know. I am so clueless at this point.</p>
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    1. COHere's a [tutorial](http://docs.oracle.com/javase/tutorial/java/IandI/index.html).
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    2. COThank you, that looks like it will be really helpful!
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