Java Packages

Java Packages

A group of similar types of classes, interfaces and sub-packages.

Built-in Package
User-defined Package

Package in java can be categorized in two form, ________ and __________.

java
lang
awt
javax
swing
net
io
util

Some example of built-in packages

Java package is used to categorize the classes and interfaces so that they can be easily maintained.
Java package provides access protection.
Java package removes naming collision.

Advantages of Java Package

Folder in a file directory

A package in Java is used to group related classes. Think of it as a ___________. We use packages to avoid name conflicts, and to write a better maintainable code.

Built-in Packages

Packages from the Java API.

User-defined Packages

Create your own package.

Java API

A library of prewritten classes, that are free to use, included in the Java Development Environment

Packages
Classes

Java API is divided into ______ and _____. Meaning you can either import a single class (along with its methods and attributes), or a whole package that contain all the classes that belong to the specified package.

import package.name.*;

Syntax when importing the whole package

import package.name.Class;

Syntax when importing a single class.

Package

import java.util.Scanner;

In the example, java.util is a ______, while Scanner is a class of the java.util package.

Class

import java.util.Scanner;

In the example, java.util is a package, while Scanner is a _____ of the java.util package.

Java Swing Tutorial

A part of Java Foundation Classes (JFC) that is used to create window-based applications. It is built on the top of AWT (Abstract Windowing Toolkit) API and entirely written in java.

Abstract Windowing Toolkit

AWT

Java Foundation Classes

JFC

Java Swing

Provides platform-independent and lightweight components.

JButton
JTextField
JTextArea
JRadioButton
JCheckbox
JMenu
JColorChooser

The javax.swing package provides classes for java swing API such as …..

Association
Inheritance

Two ways in creating a frame using Java Swing

Association

By creating the object of Frame class.

Inheritance

By extending Frame class.