What is a Package in Java

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What is a Package in Java



In Java , a  Java package is a mechanism used to group related Java classes, interfaces, and sub-packages together. Java Packages help in organizing your code, avoiding name conflicts, and controlling access to classes and members. Here’s a detailed look at Java packages:

Key Concepts

  1. Purpose of  Java Packages:

    • A Java package contains many classes.  A Java package is a collection of classes. 
    • A class is a collection of methods. A class contains many methods. 
    • Organization: Java Packages help in organizing code into logical groups. For instance, Java  classes related to user interfaces might be placed in one Java package, while those related to database operations might be in another.
    • Avoiding Name Conflicts: By placing Java classes in different Java packages, you avoid naming conflicts. For example, two different Java packages can contain classes with the same name without interfering with each other. A class name can be duplicated as long as the classes are in 2 different Java  packages. Two classes may have the same name if they are in tow different Java  packages.
    • Access Control: Packages provide access control to  Java classes and their members. For example, Java  classes in the same package can access each other’s package-private (default access) members.






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