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POChanging class variables by means of a second and third class
 

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    <p>I'm working on a personal project and at the same time experimenting with it. I've got 3 classes contained in 3 files: Calculate.java, Geometry.java, and Test.java.</p> <p>Geometry.java so far only contains some variables I want to work with, the get/set methods along with a constructor method.</p> <pre><code>package project; public class Geometry { public static double length, width; public Geometry() { this.setLength(20); this.setWidth(30); } public void setLength(double length){ this.length = length; } public void setWidth(double width){ this.width = width; } public double getLength(){ return this.length; } public double getWidth(){ return this.width; } } </code></pre> <p>Calculate.java has a public variable of type Geometry and a method to work with the variables I created in Geometry.java.</p> <pre><code>package project; import project.Geometry; public class Calculate { public static Geometry figure = new Geometry(); public static double area; public void calcArea(){ this.area = figure.getLength() * figure.getWidth(); } public double getArea(){ return this.area; } } </code></pre> <p>Finally, in Test.java I'm creating a variable c1 of type Calculate.</p> <pre><code>package project; import project.Calculate; public class Test{ public static void main(String[] args){ Calculate c1 = new Calculate; Calculate c2 = new Calculate; c1.figure.setLength(55); c2.figure.setLength(75); System.out.println("L1: "+c1.figure.getLength()+" L2: "+c2.figure.getLength()); } } </code></pre> <p>The console output is: "L1: 75 L2: 75"</p> <p>My interpretation of the output is that c1.figure and c2.figure are writing data to the same space in memory and thus, when I called <code>c2.figure.setLength(75)</code> it also altered <code>c1.figure.length</code>.</p> <p>When I first wrote this code I assumed <code>c1.figure</code> and <code>c2.figure</code> would maintain their own separate values but they don't. Is there a way to achieve this (have <code>c1.figure</code> and <code>c2.figure</code> maintain their own values without altering the other)?</p> <p>PS: First time I post here, I apologize in advance if I messed up the formatting.</p>
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