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Arun
Arun

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JAVA Notes

Toady at payilagam Institute, I revised and practiced multiple programming concepts in java. I also pushed my programs to Gitlab* and shared the updates with prithiv sir for feedback. This give me more clarity on the basics of java and improved my coding confidence.

The Topics I have covered so far are:

  1. Keywords - Reserved words in java with predefined meaning
    Example - class,pubic.

  2. Tokens - Smallest elements of a program
    Example - Keywords, Identifiers,Literals.

3.Identifiers - Names for variables,classes,method,etc.

4.Rules for Identifiers - Cannot start with digits.
- No keywords , case-sensitive and $ allowed.

5.Literals - Fixed values like numbers,strings,characters,and
booleans.

6.Declaration and Initialization - Declaration creates a variable.
- Initialization assigns value.

7.Features of java - Platform - independent,Object-oreinted,
secure and protable.

8.History of java -Created by James Gosling (1991),released in 1995

by Sun Microsystems

9.Operators - Used to perform operations (Arithmetric ,Relational,
Logical,Assignment).

10.Datatypes - Datatypes are diveded into types
1.primitivedatatypes[int,float,double,boolean,etc]
2.Non - primitive datatypes.

11.Class - Blueprint or template for creating objects.

12.Object - Instance of class with state (variables) and

Behaviour(Method)

13.Methods and types - Block of code performing tasks.
types - Predefined and user defined.

  1. Number system and conversions-Binary,Octal,Decimal,Hexadecimal.

15.Local and Instance variables - Local - Inside methods.
Instance - inside class but outside methods.

16.Compiler - compiler converts source code into bytecode
.
17.Interpreter - java visual machine interprets bytecode line by
line.

18.Installing and Running java - Install JDK,set path,write program,
compile with javac,run with java.

19.Program Excetion life Cycle - Source code -> Compilation->Bytecode
-> JVM -> Output.

I have uploaded all the programs I practised here :

Gitlab Repository Link : https://gitlab.com/Gitlab202515/rohit/-/tree/beff5b6624527f1310d35d61ecc53eb37908a09d/

Overall,Today's session helped me strengthen my basics,gain practical coding knowledge, and pick up useful shortcuts for number stytem conversions.I fell more confident in moving towards the next level of programming.

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