Java Introduction FAQ
1) What is Java?
2) What are the uses of Java?
3) What are the of import features of Java?
4) How to setup Java Environment Setup inward Windows Operating Environment?
5) What are the of import Java Language Elements?
6) What are the fundamentals of OOPS?
7) Explain nearly Java Comments?
8) What are Java Modifiers?
9) What are Java Variables?
10) What are Operators?
11) What are Methods?
12) How to direct maintain Strings inward Java?
13) What is Array?
14) How to read input inward Java?
-------------------------------------------------
1) What is Java?
• Java is a full general purpose, high marking Programming Language developed yesteryear Sunday Microsystems and released inward 1995, which was afterwards acquired yesteryear the Oracle Corporation.
• Java tin endure used to practise consummate Software Applications that may run on a unmarried reckoner or be distributed amidst servers together with clients inward a network.
• Java runs on a diversity of platforms, such every bit MS Windows, Mac, together with the diverse versions of UNIX.
• Object-orientated programming language, except the primitive information types, all elements inward Java are objects.
-------------------------------------------------
2) What are the uses of Java?
Java is used to Develop,
• Desktop Applications (Ex: Acrobat Reader)
• Web Applications (Ex: snapdeal.com)
• Enterprise Application (Ex: Banking, Insurance Applications etc...)
• Mobile Applications
• Embedded Systems.
• Smart Cards
• Games Software
• Scientific Applications
And Test Automation (with Selenium) Etc...
Note: Software evolution is the primary role of Java, secondary role is Test Automation.
-------------------------------------------------
3) What are the of import features of Java?
i) Platform Independent
Java provides software-based platform, Java code tin endure run on multiple platforms e.g. Windows,
Linux, Sunday Solaris, Mac/OS etc.
ii) Robust
Robust agency strong, Java uses potent retention management.
iii) Portable
We tin behave the coffee bytecode to whatsoever platform.
iv) Object-oriented
Object-oriented programming(OOPs) is a methodology that simplify software evolution together with maintenance
by providing closed to rules.
v) Simple
Java syntax is based on C++, removed many confusing rarely-used features, together with at that topographic point is
Automatic Garbage Collection
High-performance,
Distributed,
Architecture-neutral
and Multi-threaded Etc...
-------------------------------------------------
4) How to setup Java Environment Setup inward Windows Operating Environment?
Setup Java Environment inward social club to write together with execute Java programs.
Steps:
• Download Java Software (JDK) together with Install.
• Set Environment Variable (Path Variable).
Write Java programs using Notepad every bit Editor, Compile the Programs together with Run.
Or
• Download Java Software (JDK) together with Install.
• Download Eclipse IDE together with Extract.
Write Java Programs inward Eclipse IDE Editor together with Run
---------------------------------------------------------------
5) What are the of import Java Language Elements?
Java Language Elements
• Comments
• Data Types
• Modifiers
• Variables
• Operators
• Flow Control
Condtional Statements
Loop Statements
• Strings
• Arrays
• IO together with File handling
• Methods
Predefined
User defined
Etc...
-------------------------------------------------
6) What are the fundamentals of OOPS?
Four Fundamentals of Object Oriented Programming,
i) Inheritance
ii) Polymorphism
iii) Abstraction
iv) Encapsulation
-------------------------------------------------
7) Explain nearly Java Comments?
Comments are English linguistic communication words used for Code documentation
Purpose of Comments
a) To brand the code Readable
b) To brand the code disable from Execution
Comments Syntax inward Java
Java supports Single trouble comment together with multiple trouble comment.
a) Use // for Single trouble comment
b) Use /*..........
------------
----------
----------
-------------*/ for multiple trouble comment
8) What are Java Modifiers?
Modifiers are keywords that nosotros add together to those definitions to modify their meaning.
Two types of Modifiers inward Java
a) Access Modifiers
b) Non Access Modifiers
-------------------------------------------------
9) What are Java Variables?
Variable: Influenza A virus subtype H5N1 named retention place to shop the temporary information inside a program.
We accept Three Types of Variables inward Java
i) Local Variables
Local variables are declared inward methods or blocks.
ii) Instance Variables
Instance Variables are declared inward a course of report exactly exterior of a method or whatsoever block.
iii) Class / Static Variables
Static Variables are declared every bit static, these can't endure local.
-------------------------------------------------
10) What are Operators?
Operators are used to perform mathematical, comparing together with logical operations.
Categories of Operators inward Java
a) Arithmetic Operators
b) Relational Operators
c) Assignment Operators
d) Logical Operators
Etc...
-------------------------------------------------
11) What is Method inward Java?
A Java Method is a laid of statements that are grouped together to perform an operation.
Methods are every bit good known every bit Functions.
In structured programming (Ex: C Language) nosotros occupation Functions (Built-in together with User defined)
In Object Oriented Programming (Ex: Java Language) nosotros occupation Methods (Built-in together with User defined)
Types Methods inward Java
Two types of Methods
i) Built inward /Pre-defined Methods
ii) User defined Methods
-------------------------------------------------
12) What is String?
String is a sequence of characters written inward double quotes.
String may accept Alphabets, Numbers, together with Special Characters.
Example:
"India"
"123"
"India123"
"India*"
"india123&*"
-------------------------------------------------
13) What is Array?
In Java, Array is an Object that holds a fixed release of values of a unmarried information type.
The length of Array is established when the Array is created.
Array length is fixed, index starts from Zero.
-------------------------------------------------
14) How to read input inward Java?
There are 3 ways available inward Java for Reading input.
i) Using Scanner
ii) Using DataInputStream
iii) Using BuffuredReader
Note: Using java.util.Scanner is the easier way together with it includes many methods to cheque input is valid to read.
-------------------------------------------------
1) What is Java?
2) What are the uses of Java?
3) What are the of import features of Java?
4) How to setup Java Environment Setup inward Windows Operating Environment?
5) What are the of import Java Language Elements?
6) What are the fundamentals of OOPS?
7) Explain nearly Java Comments?
8) What are Java Modifiers?
9) What are Java Variables?
10) What are Operators?
11) What are Methods?
12) How to direct maintain Strings inward Java?
13) What is Array?
14) How to read input inward Java?
-------------------------------------------------
1) What is Java?
• Java is a full general purpose, high marking Programming Language developed yesteryear Sunday Microsystems and released inward 1995, which was afterwards acquired yesteryear the Oracle Corporation.
• Java tin endure used to practise consummate Software Applications that may run on a unmarried reckoner or be distributed amidst servers together with clients inward a network.
• Java runs on a diversity of platforms, such every bit MS Windows, Mac, together with the diverse versions of UNIX.
• Object-orientated programming language, except the primitive information types, all elements inward Java are objects.
-------------------------------------------------
2) What are the uses of Java?
Java is used to Develop,
• Desktop Applications (Ex: Acrobat Reader)
• Web Applications (Ex: snapdeal.com)
• Enterprise Application (Ex: Banking, Insurance Applications etc...)
• Mobile Applications
• Embedded Systems.
• Smart Cards
• Games Software
• Scientific Applications
And Test Automation (with Selenium) Etc...
Note: Software evolution is the primary role of Java, secondary role is Test Automation.
-------------------------------------------------
3) What are the of import features of Java?
i) Platform Independent
Java provides software-based platform, Java code tin endure run on multiple platforms e.g. Windows,
Linux, Sunday Solaris, Mac/OS etc.
ii) Robust
Robust agency strong, Java uses potent retention management.
iii) Portable
We tin behave the coffee bytecode to whatsoever platform.
iv) Object-oriented
Object-oriented programming(OOPs) is a methodology that simplify software evolution together with maintenance
by providing closed to rules.
v) Simple
Java syntax is based on C++, removed many confusing rarely-used features, together with at that topographic point is
Automatic Garbage Collection
High-performance,
Distributed,
Architecture-neutral
and Multi-threaded Etc...
-------------------------------------------------
4) How to setup Java Environment Setup inward Windows Operating Environment?
Setup Java Environment inward social club to write together with execute Java programs.
Steps:
• Download Java Software (JDK) together with Install.
• Set Environment Variable (Path Variable).
Write Java programs using Notepad every bit Editor, Compile the Programs together with Run.
Or
• Download Java Software (JDK) together with Install.
• Download Eclipse IDE together with Extract.
Write Java Programs inward Eclipse IDE Editor together with Run
---------------------------------------------------------------
5) What are the of import Java Language Elements?
Java Language Elements
• Comments
• Data Types
• Modifiers
• Variables
• Operators
• Flow Control
Condtional Statements
Loop Statements
• Strings
• Arrays
• IO together with File handling
• Methods
Predefined
User defined
Etc...
-------------------------------------------------
6) What are the fundamentals of OOPS?
Four Fundamentals of Object Oriented Programming,
i) Inheritance
ii) Polymorphism
iii) Abstraction
iv) Encapsulation
-------------------------------------------------
7) Explain nearly Java Comments?
Comments are English linguistic communication words used for Code documentation
Purpose of Comments
a) To brand the code Readable
b) To brand the code disable from Execution
Comments Syntax inward Java
Java supports Single trouble comment together with multiple trouble comment.
a) Use // for Single trouble comment
b) Use /*..........
------------
----------
----------
-------------*/ for multiple trouble comment
8) What are Java Modifiers?
Modifiers are keywords that nosotros add together to those definitions to modify their meaning.
Two types of Modifiers inward Java
a) Access Modifiers
b) Non Access Modifiers
-------------------------------------------------
9) What are Java Variables?
Variable: Influenza A virus subtype H5N1 named retention place to shop the temporary information inside a program.
We accept Three Types of Variables inward Java
i) Local Variables
Local variables are declared inward methods or blocks.
ii) Instance Variables
Instance Variables are declared inward a course of report exactly exterior of a method or whatsoever block.
iii) Class / Static Variables
Static Variables are declared every bit static, these can't endure local.
-------------------------------------------------
10) What are Operators?
Operators are used to perform mathematical, comparing together with logical operations.
Categories of Operators inward Java
a) Arithmetic Operators
b) Relational Operators
c) Assignment Operators
d) Logical Operators
Etc...
-------------------------------------------------
11) What is Method inward Java?
A Java Method is a laid of statements that are grouped together to perform an operation.
Methods are every bit good known every bit Functions.
In structured programming (Ex: C Language) nosotros occupation Functions (Built-in together with User defined)
In Object Oriented Programming (Ex: Java Language) nosotros occupation Methods (Built-in together with User defined)
Types Methods inward Java
Two types of Methods
i) Built inward /Pre-defined Methods
ii) User defined Methods
-------------------------------------------------
12) What is String?
String is a sequence of characters written inward double quotes.
String may accept Alphabets, Numbers, together with Special Characters.
Example:
"India"
"123"
"India123"
"India*"
"india123&*"
-------------------------------------------------
13) What is Array?
In Java, Array is an Object that holds a fixed release of values of a unmarried information type.
The length of Array is established when the Array is created.
Array length is fixed, index starts from Zero.
-------------------------------------------------
There are 3 ways available inward Java for Reading input.
i) Using Scanner
ii) Using DataInputStream
iii) Using BuffuredReader
Note: Using java.util.Scanner is the easier way together with it includes many methods to cheque input is valid to read.
-------------------------------------------------