Foundation For Object Generation , Data Types , Parameter & Arguments in OOP

 Foundation For Object Oriented Programming(Java)


Object Generating In Java

First we want to know about what is an object in Java.

    Object can be define as data field that has unique attributes and behaviors. Objects can correspond to real-world objects or an abstract entity.




Why We Need  Object In Java?

    • It makes it possible to use the concepts of object-oriented programming (OOP). Code can thus be arranged into reusable parts, which facilitates code reusability, scalability, and maintenance.

How To Generate Object In Java?

    • We can create any number of objects(no limit).
    • Using "new" keyword, class reference and class constructor  we can generate a new object. 

Data Types

        In computer programming, a data type is a classification that indicates the kind of value that may be stored in a variable or the type of data that can be returned by a specific expression. Programming languages are based on data types because they specify what kinds of data are available and what actions can be done with them.

        There are several data types in java.



  1. Integer (int, byte, short, long): Represents whole numbers without any decimal point.
  2. Floating-point (float, double): Represents numbers with decimal points.
  3. Character (char): Represents a single character, such as a letter or a symbol.
  4. Boolean (boolean): Represents true or false values.
  5. String: Represents a sequence of characters (text).
  6. Array: Represents a collection of elements of the same data type.
  7. Class: Objects created from classes fall under non-primitive data types. Classes are user-defined data types that encapsulate data (attributes) and behaviors (methods).
  8. Interface: Interfaces in Java define a contract for classes to implement. Objects can be of the type of the interface.



Parameters and Arguments


Parameter

    Parameters act as variables inside the method. Parameters are specified after the method name, inside the parentheses. You can add as many parameters as you want, just separate them with a comma. 

                   

Arguments

    When a method is called, its actual values are sent in as arguments. The arguments used to invoke a method must be of the same type and order as the parameters in the declaration.







Comments

Post a Comment

Popular posts from this blog

අද අපි කතා කරමු Data collections ගැන

Image
 අද අපි කතා කරමු Data collections ගැන. Data Collections ගැන කතා කරන්න කලින් අපි කතා කරමු Data Arrays ගැන. Data Array එකක් කියන්නෙ එකම වර්ගයේ Data අනුපිළිවෙලකට ගබඩා කරන්න පුලුවන් දාත්ත ව්‍යූහයක්(Data Structure). Array එකේ Type එක String නම් ඒකෙ තියෙන්න පුලුවන් String Data විතරයි. Array එකක් නිර්මාණය කරද්දි ඒකට අදාලව Fixed Size එකක් දෙන්න ඕනි. Array එකක් හැදුවට පස්සෙ අපට Array එක වෙනස් කරන්න බෑ. ex:-  int[] array = new int[5];         array[0] = 1;                 array[1] = 2;                 array[2] = 3;                 array[3] = 4;                 array[4] = 5; එතකොට මොනාද මේ Array වල තියෙන ප්‍රශ්න?      මම මුලින් කිව්වා වගේ Array එකක් හදනකොට අපි ඒකට Fixed Size එකක් දෙන්න ඕනි. දැන් ඔයාලා හිතන්නකො අපි Size එක 5ක් වෙන Array එකක් හදනවා integer වලින්. එතකොට අපිට ඒ Array එකට ඇඩ් කර...
Read more

Understanding and Mastering Coding Errors

Image
 Understanding and Mastering Coding Errors      Coding errors are an inevitable part of the software development journey. Whether you're a novice programmer or a seasoned developer, encountering errors is something you can count on. But rather than seeing them as roadblocks, errors can be powerful learning tools that help you write better code.      There are 3 main types of errors.                     1.Syntax Errors 2.Logical Errors 3.Runtime Errors 1.Syntax Errors:-      Syntax errors occur when the code violates the rules of the programming language. These errors are usually detected by the compiler during the initial stages of program execution. Common examples include missing semicolons, mismatched parentheses, or misspelled keywords.               Above code, semicolon is missed. That is a syntax error. If there any syntax er...
Read more

OOP key points

Image
Key Points Of Object Oriented Programming (OOP) Object Oriented Programming:- It is a computer programming model based on object. We can use it in various programming languages to develop a program.  Building Blocks of OOP Object:-             Object can be define as data field that has unique attributes and behaviors.              Objects can correspond to real-world objects or an abstract entity.      2.Class:-              Class  is a sketch used to implement an object at the programming level.               And also we an define class as "A template that can keep the things what we need".   3.Method:-                A method in OOP is a block of code that, when called, performs specific actions mentioned in it.    4.Variable:- ...
Read more