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Ricardo Caselati
Ricardo Caselati

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Exploring Class Organization with Packages in Java

In the Java world, organization is key, and packages play a vital role in achieving it. Packages act as virtual directories that group classes, making your projects more structured and scalable.

When you create a class without specifying a package, it resides in the default package. However, by using named packages like com.example.project, you not only improve your code organization but also adhere to Java’s common best practices. The package name reflects the directory structure—for instance, com.example.project indicates that the class is located in src/com/example/project/.

How to Access Classes from Other Packages?

This is where the import statement comes in. It allows you to use external classes in your code, either broadly (import package.*) or specifically (import package.Class).

Here’s an example:

package com.myProject.helloworld;  
import java.lang.*;  
import java.lang.Math;  

public class SquareRootOfTwentyFive {  
    public static void main(String[] args) {  
        System.out.println("The square root of twenty-five is:");  
        System.out.println(Math.sqrt(25));  
    }  
}  
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In this example, to use mathematical methods like Math.sqrt(25), you simply need to import the java.lang.Math class, one of Java's many utility classes. This functionality enhances modularity and reusability, which are crucial for building robust and collaborative projects.

Let Java's package system guide your project structure toward clean, scalable, and professional code.

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