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SSDN Technologies is one of the leading training center, offering the 6 weeks summer training opportunity with Live Project industrial training and internship in Gurgaon
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6 Weeks Summer Training On Java By SSDN Technologies Call us at 0124-4018080 / +91-9999509970
An overview on Java • What is JAVA? • What is OOP? • Why Java? • Characteristics of JAVA • Overview of Java. • The difference between Java and C++? • A Simple JAVA Program Call us at 0124-4018080 / +91-9999509970
What is JAVA? • Developed by Sun Microsystems (James Gosling) • A general-purpose Object-Oriented language • Based on C/C++ • Designed for easy Web/Internet applications • Widespread acceptance Call us at 0124-4018080 / +91-9999509970
What is OOP ?? Object-oriented programming is a method of implementation in which programs are organized as cooperative collections of objects, each of which represents an instance of some class, and whose classes are all members of one or more hierarchy of classes united via inheritance relationships. Call us at 0124-4018080 / +91-9999509970
Principles of OOP There are three main features of OOPS. 1) Encapsulation 2) Inheritance 3)Polymorphism Let’s we discuss about the about features in details. Call us at 0124-4018080 / +91-9999509970
Encapsulation Encapsulation means putting together all the variables and the methods into a single unit called Class. It also means hiding data and methods within an Object. Encapsulation provides the security that keeps data and methods safe from inadvertent changes. Advantages of Encapsulation • Protection • Consistency • Allows change Call us at 0124-4018080 / +91-9999509970
Inheritance An important feature of object-oriented programs is inheritance— the ability to create classes that share the attributes and methods of existing classes, but with more specific features. Inheritance is mainly used for code reusability In general one line definition we can tell that deriving a new class from existing class, it’s called as Inheritance. Call us at 0124-4018080 / +91-9999509970
Polymorphism Polymorphism is an object-oriented programming concept that refers to the ability of a variable, function or object to take on multiple forms. A language that features polymorphism allows developers to program in the general rather than program in the specific. 2ways to implement polymorphism. • Static Polymorphism (compile time) • Dynamic Polymorphism (run time) Call us at 0124-4018080 / +91-9999509970
Static Polymorphism Compile time polymorphism is nothing but the method overloading in java. In simple terms we can say that a class can have more than one methods with same name but with different number of arguments or different types of arguments or both. To know more about it refer methodoverloading in java. Call us at 0124-4018080 / +91-9999509970
Run Polymorphism Method overriding is a perfect example of runtime polymorphism. In this kind of polymorphism, reference of class X can hold object of class X or an object of any sub classes of class X. For e.g. • If class Y extends class X then both of the following statements are valid: • Y obj = new Y(); • Parent class reference can be assigned to child object X obj = new Y(); Call us at 0124-4018080 / +91-9999509970
Why Java An Object oriented programming language developed in the early ‘90s. The language itself takes much of its syntax from C and C++ but has a simpler object model and eliminates low-level tools. It is platform independent. Early implementations of Java had the slogan: “write once, run anywhere” It has a system of automatic memory management. Call us at 0124-4018080 / +91-9999509970
Java, Web, and Beyond • Java Applets • Java Web Applications • Java can also be used to develop applications for • hand-held devices such as Palm and cell phones Call us at 0124-4018080 / +91-9999509970
Characteristics of Java •Java Is Simple •Java Is Object-Oriented •Java Is Distributed •Java Is Interpreted •Java Is Robust •Java Is Secure •Java Is Architecture-Neutral •Java Is Portable •Java's Performance •Java Is Multithreaded •Java Is Dynamic Call us at 0124-4018080 / +91-9999509970
Java Disadvantages Slower than compiled language such as C An experiment in 1999 showed that Java was 3 or 4 times slower than C or C++ Call us at 0124-4018080 / +91-9999509970
Origin of Java James Gosling & Patrick Naughton at 1990 Goal : To develop distributed system which is applicable to electronic products (platform independent) Call us at 0124-4018080 / +91-9999509970
JDK Versions •JDK 1.02 (1995) … 250 classes •JDK 1.1 (1996) … 500 classes •JDK 1.2 (1998) … 2300 classes •JDK 1.3 (2000) … 2300 classes •JDK 1.4 (2002) … 2300 classes •JDK 1.5 (2004) … 3500 classes •JDK 1.6 (2006) … 3500 classes •JDK 1.7 (2011) … 3500 classes Call us at 0124-4018080 / +91-9999509970
Java life cycle Java programs normally undergo four phases • Edit Programmer writes program (and stores program on disk) • Compile Compiler creates byte-codes from program (.class) • Load Class loader stores byte-codes in memory • Execute Interpreter: Translates byte-codes into machine language Call us at 0124-4018080 / +91-9999509970
Java life cycle • Source code (.java) • Compiled into Byte codes (.class) , as (.exe) in c++ • The Java Application Programming Interface • a large collection of ready-made software components. It is grouped into libraries of related classes and interfaces; these libraries are known as packages. – Java Virtual Machine (JVM) – Machine code Call us at 0124-4018080 / +91-9999509970
Slide Title Call us at 0124-4018080 / +91-9999509970
Simple Java Program This program prints Welcome to Java! public class Welcome { public static void main(String[] args) { System.out.println("Welcome to Java!"); } } Call us at 0124-4018080 / +91-9999509970