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Understanding Inheritance in Java

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  Inheritance in Java Inheritance is a fundamental concept in Java and many other object-oriented programming languages. It allows a new class, called a subclass, to inherit the properties and behaviors (methods) of an existing class, known as a superclass. This promotes code reusability and a hierarchical classification. Key Concepts Superclass and Subclass : Superclass : The class whose properties and methods are inherited. Subclass : The class that inherits properties and methods from the superclass. Inheritance Syntax : In Java, inheritance is implemented using the extends keyword. Here is a simple example: // Superclass class Animal { void eat () { System.out.println( "This animal eats food." ); } } // Subclass class Dog extends Animal { void bark () { System.out.println( "The dog barks." ); } } public class Main { public static void main (String[] args) { Dog myDog = new Dog (); myDo...

Main Method & Constructors | in Java

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  Main Method  āļĸා⎀ා ⎀āļŊ āļ…āļ´ි āļ¸ුāļŊිāļą්āļ¸ āļ‰āļœෙāļą āļœāļą්āļą Method āļ‘āļš āļ­āļ¸āļēි āļ¸ේāļš.āļ¸ේ āļ‡āļ­ුāļŊෙ āļ­āļ¸āļēි āļ…āļ´ි Method āļšෝāļŊ් āļšāļģāļą්āļąෙ object ⎄āļ¯āļą්āļąෙ āļšොāļ§ිāļą්āļ¸ āļšි⎀්⎀ොāļ­් āļ…āļ´ි āļœāˇ„āļą āļšෝāļŠ් āļ‘āļš Execute āļšāļģāļą්āļąෙ āļ¸ේāļšෙ āļ‡āļ­ුāļŊෙ āļ­āļ¸āļēි.    public void main(String[] args){      System.out.println("Hello");    } Constructor Constructor āļ‘āļšāļš් āļšිāļēāļą්āļąේ method āļ‘āļšāļš්. ⎄ැāļļැāļēි āļ¸ේāļšෙāļą් ⎀ෙāļą āˇ€ැāļŠේ ⎀ෙāļą්āļąේ class āļ‘āļšāļš් āļ´ා⎀ිāļ ්āļ ි āļšāļģāļŊා object āļ‘āļšāļš් ⎄āļ¯āļąāļšොāļ§.Class āļ‘āļšāļš් āļ‡āļ­ුāļŊේ āļ­āļ¸āļēි Constructor āļ‘āļšāļš් ⎄āļ¯āļą්āļąේ. āļ…āļ´ි constructors āļˇා⎀ිāļ­ා āļšāļģāļą්āļąේ.āļ…āļ´ේ code āļ‘āļš āļ‘⎄ෙāļ¸āļ­් āļąැāļ­්āļąāļ¸් software āļ‘āļš run ⎀ෙāļą්āļą āļ´āļ§āļą් āļœāļ¯්āļ¯ිāļ¸ āļ¯ෙāļą්āļą āļ•āļąි commands āļ§ිāļš āļŊāļļාāļ¯ෙāļą්āļą.  āļ´āˇ„⎅ āļ­ිāļēෙāļą Example code āļ‘āļš āļļāļŊāļą්āļą. class Car { Car() { // constructor body } } āļ¸ේāļš āˇƒාāļ¸ාāļą්‍āļē method āļ‘āļšāļš් āļąෙāļ¸ෙāļēි āļąි⎃ා Constructor āļ‘āļšāļš් ⎄āļ¯āļąāļšොāļ§ āļ‘āļšāļ§ rules āļ­ිāļēෙāļąāˇ€ා. Constructor āļ‘āļšේ āļąāļ¸ Class āļ‘āļšේ āļąāļ¸āļ§ āˇƒāļ¸ාāļą āˇ€ෙāļą්āļą āļ•āļąේ Constructor āļ‘āļšāļ§ return type āļ‘āļšāļš් āļąැ . āļ…āļ´ි Class āļ‘āļšāļš් ⎄āļ¯āļąāļšොāļ§ Constructor āļ‘āļšāļš් ⎄ැāļ¯ු⎀ේ āļąැāļ­āļ­් Java compiler āļ‘āļšෙāļą් automatically āļ¸ code āļ‘āļš run ⎀ෙāļ¯්āļ¯ිāļ¸ āˇ„āļ¯āļą āˇ€ා....

Data types in java | Access modifiers

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Data Types Data store āļšāļģāļŊා āļ­ිāļēාāļœāļą්āļą āļ´ුāļŊු⎀āļą් ⎀ි⎀ිāļ° āļŠේāļ§ා categories āļ…āļ´ිāļ§  Data types āļŊෙ⎃ ⎄āļŗුāļą්⎀āļą්āļą āļ´ුāļŊු⎀āļą්. āļĸා⎀ා ⎀āļŊāļ¯ි āļ…āļ´ි āļ¸ේ⎀ා ⎄āļŗුāļą්⎀āļą්āļąේ Primitive Data Types āļšිāļēāļŊා. Primitive Data Types Primitive data types āļšිāļēāļą්āļąේ Java language āļ‘āļšේ āļ´āˇ€āļ­ිāļą āļ¸ුāļŊිāļš data types ⎀ේ āļ¸ෙ⎄ිāļ¯ී āļ¸ෙāļ¸ data types āļšොāļ§āˇƒ් 2āļšāļ§ āļļෙāļ¯āļą්āļą āļ´ුāļŊු⎀āļą් numerical  ⎄ා non numerical āļšිāļēāļŊ. Numerical Data Types ⎃ංāļ›්‍āļēාāļ¸āļē āļ¯āļ­්āļ­ āļœāļļāļŠා āļšāļģāļŊ āļ­ිāļēාāļœāļą්āļą āļ´ුāļŊු⎀āļą් data types ⎄āļŗුāļą්⎀āļą්āļą āļ´ුāļŊු⎀āļą් Numerical data types   āļšිāļēāļŊා. Byte āļ¸ේ data type āļ‘āļš āļˇා⎀ිāļ­ āˇ€ෙāļą්āļąෙ  āļ´ූāļģ් āļĢ  āˇƒංāļ›්‍āļēා ⎃āļ¸āļœ āˇ€ැāļŠ āļšāļģāļ¯්āļ¯ි. āļ¸ේ data type āļ‘āļš 8 bit data type āļ‘āļšāļš්. āļ’ āļšිāļēāļą්āļąෙ āļ¸ේ data type āļ‘āļšේ variable āļ‘āļšāļš bit 8 āļš āļ­ොāļģāļ­ුāļģු āļģāļŗāˇ€āļœāļą්āļą āļ´ු⎅ු⎀āļą්. āļšෙāļ§ිāļēෙāļą් āļšි⎀්⎀ොāļ­් 1 bit āļ‘āļšāļš data 2 1  āļ´්‍āļģāļ¸ාāļĢāļēāļš් āļģāļŗāˇ€āļœāļą්āļą āļ´ු⎅ු⎀āļą්. āļ‘āļ­āļšොāļ§ byte variable āļ‘āļšāļš 2 8  data āļ´්‍āļģāļ¸ාāļĢāļēāļš් (⎃ංāļ›්‍āļēා 512āļš්) āļģāļŗāˇ€āļœāļą්āļą āļ´ු⎅ු⎀āļą්. byte variable āļ‘āļšāļš āˇƒෘāļĢ āļ°āļą āļ…āļœāļēāļą් āļ¯ෙāļšāļ¸ āļģැāļŗāˇ€ිāļē ⎄ැāļšි āļąි⎃ා -128 ⎃ිāļ§ 127 āļ¯āļš්⎀ා ⎃ංāļ›්‍āļēා āļģāļŗāˇ€āļą්āļą āļ´ු⎅ු⎀āļą්. Short āļ¸ේāļšāļ­් āļ´ූāļģ් āļĢ āˇƒංāļ›්‍āļēා ⎃āļŗāˇ„ා āļˇා⎀ිāļ­ āˇ€āļą data type āļ‘āļšāļš්. āļ¸ෙāļē byte ⎀āļŊිāļą් ⎀ෙāļąāˇƒ්...

Object Oriented Programming (OOP) | In Sinhala

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Object Oriented Programming (OOP) Standards of OOP Standards in  Class  Class āļ‘āļšāļšāļ§ āļąāļ¸āļš් āļēෙāļ¯ීāļ¸ේāļ¯ී ⎃ාāļ¸ාāļą්‍āļēāļēෙāļą් āļ‘⎄ි āļ´āˇ…āļ¸ු āļ…āļšුāļģ āˇƒāļŗāˇ„ා Capital āļ…āļšුāļģāļš් āļēොāļ¯āļąු āļŊāļļāļēි.āļ¸ෙāļ¸āļœිāļą් Class āļ‘āļš Variable ⎀āļŊිāļą් ⎄ා Function/Methods ⎀āļŊිāļą් ⎀ෙāļą් āļšāļģ ⎄āļŗුāļąාāļœැāļąීāļ¸āļ§ āļ´āˇ„āˇƒු ⎀ේ. Ex :   āļ­āˇ€āļ¯ Class āļ‘āļšෙ⎄ි āļąāļ¸ āˇƒāļŗāˇ„ා ⎀āļ āļą 2āļš් āļēෙāļ¯ීāļ¸ේāļ¯ී Space āļąොāļ­āļļා āļ‘āļšāļ§ āļēොāļ¯āļą āļ…āļ­āļģ āļ´āˇ…āļ¸ු ⎀āļ āļąāļē Simple āļ…āļšුāļģු ⎀āļŊිāļąුāļ­් āļ¯ෙ⎀āļą āˇ€āļ āļąāļēේ āļ´āˇ…āļ¸ු āļ…āļšුāļģ āļ´āļ¸āļĢāļš් Capital ⎀āļŊිāļąුāļ­් āļ‰āļ­ිāļģි āļ…āļšුāļģු Simple   āˇ€āļŊිāļąුāļ­් āļēොāļ¯āļąු āļŊāļļāļēි.āļ¸ෙāļē camel case āļēāļąු⎀ෙāļą් ⎄āļŗුāļą්⎀āļēි. Ex :  Standards in  Variable Variable āļąāļ¸් āļšිāļģීāļ¸ේāļ¯ී Simple āļ…āļšුāļģු āļˇා⎀ිāļ­ා āļšāˇ… āļēුāļ­ුāļē. ⎀āļ āļą 2āļš් āˇƒāˇ„ිāļ­āˇ€ āļąāļ¸් āļšිāļģීāļ¸ේāļ¯ී ⎃ාāļ¸ාāļą්‍āļēāļēෙāļą් āļšිāļē⎀ීāļ¸ේ ⎄ැāļšිāļēා⎀ ⎀ැāļŠි āļ¯ිāļēුāļĢු āļšිāļģීāļ¸ āˇƒāļŗāˇ„ා āļēāļ§ි āļ‰āļģි āļ¸āļœිāļą් ⎀ෙāļą් āļšāļģāļąු āļŊැāļļේ. Ex :  Standards in  Methods M ethod āļ‘āļšāļš් ⎃ෑāļ¯ීāļ¸ේāļ¯ී āļ‘⎄ි āļąāļ¸āļ§ āļ´āˇƒු⎀ ( ) āļēෙāļ¯ීāļ¸ āļ…āļąි⎀ාāļģ්‍āļē ⎀ේ. āļ¸ෙāļē Parameter āļŊෙ⎃ ⎄āļŗුāļą්⎀āļēි. Ex :   Classes, Variables, Methods āļąāļ¸් āļšිāļģීāļ¸ේāļ¯ී āļ´āˇ„āļ­ āˇƒāļŗāˇ„āļą් ⎀āļ āļą āļˇා⎀ිāļ­ා āļšāļŊ āļąො⎄ැāļšි āļ…āļ­āļģ āļ¸ේ⎀ා Key Words āļŊෙ⎃ ⎄āļŗුāļą්⎀āļēි. Object āļ‘āļšāļš් āļēāļąු … āļŊāļš්⎂āļĢ(Properties) ⎄ා ⎄ැ⎃ිāļģ්‍āļģ්āļ¸්...