IMRAN DAUD FOUNDATION UNIVERSITY RAWALPINDI CAMPUS Imran Daud FURC Web Engineering Introduction

Content to be covered HTTP Architecture HTML Basics Applets JSP Java Servlets Java Scripts

Marks Distribution Project/Assignment/ Quizes 15% Mid Term 30% Attendance 5% Final 50%

Java ABC Imran Daud FURC High Level language What are Java Packages? How we use Packages? How do we write Java Program? How to compile Java program? what is.class file? How to run Java program? Java as OOP Java Documentation

High level language Imran Daud FUIMCS Closer to human languages They are easier to read, write, and maintain Platform independent.

Packages? Imran Daud FUIMCS organizing Java classes into namespaces similar to the modules. Packages stored into JAR files to allow classes to download faster in group rather then one at a time Package contains:  Classes  Interfaces

How to use Java Packages? Imran Daud FUIMCS import java.awt.event.*; Keyword: import Hierarchy of classes. Each packages contain different set of classes Each class can use protected data member and data functions directly of other classes within same package.

How to Write java program Imran Daud FUIMCS Case Sensitive. Class based coding. Has ‘main’ function. class name and file name should be same. Objects instantiated in main using new keyword. Save file with extension ‘.java’ Example:

Compiling java code in Dos mode Imran Daud FUIMCS ‘Bin’ folder Path to be defined. Use ‘javac’ command to complie. javac File_name.java After compiling ‘File_name.class’ is generated.

What is.class file Imran Daud FUIMCS Bytecode If a file contains more then one classes then a separate.class file will be generated for each class. ‘.class’ file can be run with JVM.

How to run java program (Dos shell) Imran Daud FUIMCS Use ‘java’ command to run.class file. Example: Java File_name

Java as OOP Imran Daud FUIMCS Java is based on OOP concepts. Main feature of OOP is inheritance. We inherit classes using ‘extend’ keyword. Public Class My_prog extends InheritedFile { } we make objects to access data members or data functions.

Class VS Interface ‘extend’ Class whereas ‘implement’ interface Class can have instance but interface don’t Re-declare ALL functions in interface.

Java Documentation Imran Daud FUIMCS How to use API (Demo)

References Imran Daud FUIMCS en.Wikipedia.org