The package Statement in Java Programming

The package Statement in Java Programming

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A Java package is a mechanism for organizing Java classes into namespaces similar to the modules of Modula. 

Java packages can be stored in compressed files called JAR files, allowing classes to download faster as a group rather than one at a time. Programmers also typically use packages to organize classes belonging to the same category or providing similar functionality.
A package provides a unique namespace for the types it contains.
Classes in the same package can access each other's package-access members.
 In a Java source file, the package that this file's class or classes belong to is specified with the package keyword.
 This keyword is usually the first keyword in source file

 To use a package's classes inside a Java source file, 
it is safe to import the classes from the package with an import declaration.
import java.awt.event.|*;

how to create a package
package com.mycompany.myproject;

import java.util.*;

class MyClass {

}

java.lang      for basic language functionality and fundamental types
java.util      for collection data structure classes
javax.swing      for hierarchy of packages for platform-independent rich GUI components
java.math      for multiprecision arithmetics
java.sql      for Java Database Connectivity (JDBC) to access databases
java.net      for networking operations, sockets, DNS lookups, ...
java.security      for key generation, encryption and decryption
java.applet      for classes for creating an applet
java.awt      for basic hierarchy of packages for native GUI components
java.io      for file operations


 

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