Introduction to Java

• Importance of Java
  • Integral to internet and smartphone usage
  • Facilitates day-to-day tasks within homes
  • Supports online shopping, banking, and booking

Overview of Java

• Definition

  • High-level, class-based, object-oriented programming language
  • Created by James Gosling and Sun Microsystems in 1991
  • Known for the principle: "Write once, run anywhere"

• History

  • Originally named Oak
  • Changed to Green, then Java Coffee, and finally Java in 1995

Java Editions

• Java Standard Edition (SE)

  • Contains core libraries (e.g., java.lang, java.util)

• Java Enterprise Edition (EE)

  • Includes APIs (e.g., JMS, EJB, JSP, Servlets)

• Java Micro Edition (ME)

  • Used for programming on mobile devices and handhelds

Java’s Technical Features

• Object-Oriented Principles

  • Based on C and C++ but improved and simplified
  • Uses classes and methods to organize code
  • Methods
    • Blocks of code that perform tasks when called
    • Example: Changing TV channels with remote buttons

• Execution

  • Java files compiled into bytecode
  • Executed by the Java interpreter on the Java Virtual Machine (JVM)

Features of Java

• Simplicity

  • Easy syntax and learning curve

• Robustness

  • Error elimination mechanisms
  • Features like garbage collection and exception handling

• Platform Independence

  • Compiled into bytecode, can run on any machine

• Security

  • No inherent viruses

• Multi-threading

  • Supports multitasking

• Portability

  • Fixed data type sizes

• Performance

  • Not as fast as C/C++, but higher performance than other languages

Object-Oriented Programming Concepts (OOPS) in Java

• Main Concepts
  1. Abstraction
     • Hides unnecessary details, shows relevant information
  2. Encapsulation
     • Protects data within classes, ensuring security
  3. Inheritance
     • Allows one class to inherit attributes from another, facilitating code reuse
  4. Polymorphism
     • Same method can perform different tasks in different contexts

Conclusion

• Encouragement to keep learning and staying tuned for more information.