java package is a group of similar types of classes, interfaces and sub-packages.
Syntax
Creating a package
package com.example.myapp;
Compiling a package
javac -d directory javafilename
Importing a package
package thisPackage;
import com.example.myapp;
public Class{
If you import a package, all the classes and interface of that package will be imported excluding the classes and interfaces of the subpackages. Hence, you need to import the subpackage as well.
Default Package
If you do not specify a package for your classes, they will be placed in the default package. However, it is recommended to always use packages to avoid naming conflicts and make your code easier to manage.
Package Naming Conventions
Package names in Java follow the reverse domain name convention. For example, if a company owns the domain name example.com, they would use the following package name:
package com.example.myapp;
Package-level Annotations
Java also allows you to add annotations at the package level. These annotations apply to all classes and interfaces in the package. For example:
@Deprecated
package com.example.myapp;
This marks the entire package as deprecated, and any usage of classes or interfaces within the package will generate a warning.