Fundamentals of Java Programming - Lesson 2

1. Basic Java Programming
Sasidhara Marrapu

2. Introduction to Java Programming
– Environment Setup
 Java Overview?
 Features of Java?
 Components of Java
 JVM, JDK and JRE
 Steps to Write Program?
 Basic Java Syntax & Rules
 Comments, Package, Imports
 Class Structure
 Constructor
 Variables/Properties
 Methods -Main
 Java IDEs
 Lab Problem
 Java – Environment Setup
 Download and Install
 Set Environments
 Write Your First Program
 Install Eclipse IDE
 Create Workspace
 Write Program and Execute
 Home Work
 Write Programs and Execute

3. What is Java?
• Easy English like Language
• Developed by James Gosling
in 1995 for Sun Microsystems
• Java is an object-oriented language
similar to C++, but with advanced and
simplified features.
• Java is free to access
• Write Once and Run Any Where

4. Features of Java

5. Components of Java:

6. Components of Java:
• JVM (Java Virtual Machine)
• Execute the bytecode produced by compiler.
• Each operating system has different JVM
• JRE (Java Runtime Environment)
• JRE includes JVM, browser plugins and applets support.
• When you only need to run a java program on your computer, you would only
need JRE.
• JDK (Java Development Kit)
• Java development kit that includes JRE (Java Runtime Environment), compilers
and various tools like JavaDoc, Java debugger etc.
• In order to create, compile and run Java program you would need JDK

7. Java Environment Setup:
• Install JDK
• Setup Environment Variables
• PATH
• CLASSPATH
• Verify
• Write Our First Java Program

8. Steps to Write Program:
• Type the Program – Source Code
• Compile to Bytecode
• Run the program
compile execute
output
source code
Hello.java
byte code
Hello.class

9. How It Work?

10. IDE Setup:
• Install Eclipse
• Create Project
• Write Our First Java Program

11. Basic Structure and Syntax of Java:
public class HelloJava {
public static void main(String args[]){
System.out.println("Hello Java World");
}
}

12. Basic Structure and Syntax of Java:
• Case Sensitivity
• Class Names
• Example: class MyFirstJavaClass
• Method Names
• Example: public void myMethodName()
• Program File Example: Assume 'MyFirstJavaProgram' is the class
name. Then the file should be saved as 'MyFirstJavaProgram.java'
• public static void main(String args[]) - Java program processing
starts from the main() method which is a mandatory part of every
Java program.

13. Class Structure :
package <package name>
Import <package name>.* or <class name>
/* comments */
public class <class name> {
private String <variable name>
/*Constructor */
public <class name> (){
}
//Methods
public static void main(String args[]) {
<statement>;
<statement>;
...
<statement>;
}
public <return type> <method name>(<parameters>){
<statement>;
<statement>;
...
<statement>;
}
}

14. Basic Structure and Syntax of Java:
Comments:
Single line
// compiler ignores everything to end of line
Multi-line
/* compiler ignores everything in between */
Block/Multi-line (documentation)
/** compiler ignores everything in between */
Comments do not appear in executable code

15. Home Work