This document provides an introduction to the Java programming language. It discusses Java's characteristics such as being architecturally neutral, portable, robust, and object-oriented. The document explains object-oriented features in Java like encapsulation, polymorphism, inheritance, and dynamic binding. It also lists some important classes in Java like Class, Throwable, Runtime, and Math. The document is intended to provide a high-level overview of Java for fresher developers.

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Introduction To Java
Fresher’s 2016

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Characteristics of Java
 Architectural Neutral
 High Performance
 Distributed
 Portable
 Secure
 Robust
 Object Oriented ??
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Object Oriented Language
 Fully support Encapsulation and Abstraction
 Must support Inheritance
 Must support Polymorphism
 All predefined must be Objects
 All user defined types must be Objects
 All operations performed on objects must only be through methods exposed
by object.
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Object Oriented Features of Java
• Encapsulation
• Implements information hiding and modularity (abstraction)
• Polymorphism
• Same message sent to different objects results in behavior that's
dependent on the object receiving the message
• Inheritance
• Define new classes and behavior based on existing classes to help code
re-use.
• Dynamic binding
• You need to be able to send messages to objects without having to know
their specific type at the time you write your code.
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Single Inheritance Model
• Everything is derived from Object class.
• https://docs.oracle.com/javase/7/docs/api/java/lang/package-tree.html
• http://docstore.mik.ua/orelly/java-ent/jnut/figs/JN3_1201.gif
• Except for few interfaces
• Runnable
• Serializable
• Cloneable
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Some Important Classes
• Class
• Every class has an Class Object.
• Throwable
• Parent for Exception, Error
• Runtime
• Interact with the Runtime Environment
• System
• Loading libraries, I/O, Properties
• ProcessBuilder
• Create OS Process
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• ClassLoader
• Loads Classes, used by Security Manager
• SecurityManager
• Implements security policy
• Package
• Find information about loaded packages
• Math
• Mathematical functions
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Some Important Classes Continued

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Q
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S
T
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What’s Next
• Data Types
• Operators
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Thanks
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