this ppt will give u brief introduction about core java.

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CONTENTS:
 History
 Featurs of Java
 JDK & JRE, Bytecode & JVM
 Classes and objects
 Inheritance & Interfaces
 Multithreading
 Applets
 Advantages & Disadvantages

3. HISTORY OF JAVA
 Developed by Sun microsystems (U.S.) in 1991.
 Was designed for development of software for electronic devices.
 A team headed by James Gosling was formed to undertake this task.
 OOPs Language C++ was explored resulting in new language ‘Oak’.
 This team, The Green Project Team, demonstrated an application to
control home appliances using hand held touch screen device in 1992.
 In 1993, with www, this team game up with the idea of developing web
Applets using this language, to run on all types of connected computers.
 In 1994, the team developed ‘Hot Java’ browser.
 Oak was renamed to JAVA in 1995, due to legal snags.
 By the time of 1996, java established itself as a leader of Internet
Programming and a general purpose OOPs language.
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4. FEATURES OF JAVA
 Simple
 Truly Object Oriented
 Platform Independent
 Distributed
 Interpreted
 Secure
 Robust
 Multithreaded
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5. JDK AND JRE
• Java Runtime Environment (JRE) includes no of
development tools , classes and methods.
• Java Development Kit (JDK) is collection of tools used for
developing and running programs. This includes:
 Appletviewer: enables us to run Applets (without browser).
 Java: interpreter, reads bytecode files, runs Applets and
applications.
 Javac: compiler, translates source code to byte code files, that is
readable by interpreter.
 Jdb: java debugger
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6. BYTE CODE & JVM
 A program exists in two forms: source code & object code.
 The program written in editor is source code.
 Executable form of this code is called as object code.
 Java compiler generates an object file containing bytecode.
 This bytecode is executable on any specific CPU.
 Java Virtual Machine (jvm) is a virtual machine, that can
execute this bytecode using interpreter.
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7. Java
Program
Java
Compiler
Java
Virtual
Machine
PROCESS OF COMPILING
Bytecode
Java
Interprete
r
Machine
Code
CONVERSION OF BYTECODE INTO MACHINE CODE
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8. Java Runtime Environment (JRE)
Java API Class JVM
Operating System
(Windows, Linux etc)
Hardware
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9. CLASSES & OBJECTS
 An object is a bundle of related state and
behavior.
 Software objects are used to model real world
objects.
 A collection of objects is known as Class.
 Classes can be considered as a blueprint from
which objects are derived.
e.g. the statement fruit mango
creates an object mango of class fruit
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10. A SIMPLE HELLO WORLD PROGRAM
class HelloWorldApp
{
public static void main (String args[])
{
System.out.println(“Hello World”);
}
}
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11. INHERITANCE
 Enables user to derive new classes from existing ones.
 Class derived from other class is called Subclass (also as
derived class, extended class or child class)
 Class getting derived is known as Superclass (also a base
class or a parent class)
Syntax :
class subclassname extends superclassname
{ variables declaration;
methods declaration;
}
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12. EXCEPTION HANDLING
 It is a customary way to indicate abnormal
condition.
 A method encountering abnomalities, thows an
exception.
 Exceptions are caught by handlers.
 Handlers these are positioned along method
invocation stack.
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13. Throwable
Exception Error
Interrupted
Exception Runtime
Exceptions
Thread
Death
Throwable Family
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14. MULTITHREADING
 It is a specialised form of multitasking
 A thread is similar to a program with single flow
of control.
 A thread can be considered as a subprogram.
 Each thread runs parallel to each other.
 Java Interpreter handles switching of control
between threads such that they seem to run
concurrently.
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15. APPLETS
 These are small programs used in Internet
Computing.
 Can be transferred over internet from system to
system.
 Can run anywhere using Applet Viewer or any
Java enabled browser.
 Applets are not full featured or stand alone
programs.
 They run inside web page using HTML tags.
 Used for graphics, sounds play, arithematic
operations, accept user input, animations,
interactive games etc
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16. WHAT CAN JAVA TECHNOLOGY DO?
 Development Tools
 Application Programming Interface (APIs)
 Deployment Technologies
 User Interface Toolkits
 Integration Libraries
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17. ADVANTAGES:

18. DISADVANTAGES
 Slow Performance (10 to 20 times slower than c++)
 Compiling takes time
 Too much error checking
 Interpreter takes time too
• Memory management is expensive.
• Java being a high level language, does not offers
freedom to use on embedded systems.

19. REFERENCES:
 Mrs.Faiyaz Alam, Appin, Alwar
 Core Java Study Materials, Appin
 Programming With Java book by
E.Balaguruswami
 Java Programming book by Vikash Thada
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21. THANK
YOU ALL
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