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Data Type Concept in Java?

Datatype :-  It is used to represent pattern and size of data in memory .Datatype always will be used in variable,constant ,method ,array etc.

Java Support all datatype of C and C++ Language:-

Type of datatype:-

1 Primitive:-

  1.1) byte:-  1 byte
  1.2) int :-   4byte
  1.3) float :- 8byte
  1.4) double:-  16byte
  1.5) char:- 2byte
  1.6) boolean :-  1byte


2 Non Primitive:-
   It's size is not fixed ,it's depend on memory type and data.

  2.1 Object  ---> Common Type which contain all type data
   Object o=10;

  2.2 String  ---> Collection of Chars
  2.3 StringBuffer
 2 .4 StringBuilder
 2.5 Integer
 2.6  Float
 2.7 Array
 2.8 Collection
 2.9 DateTime
 2.10 enum

........................................................................................
QUESTION :-  Why java is not 100% Object Oriented?

Answer:-   Java support primitive datatype int,char,float ,double ,these all are datatype is written in C and C++ programming language hence Java program code support native code hence it is not 100% object oriented.

Question :-  What is native code in Java?

Answer:-  c and c++ programming language code is called native code in java hence java contain native library under JRE.


Question:- WAP to perform addition of two number without int,float and double datatype or primitive datatype?

Answer:-  


Question what is implicit and explicit conversion in java?
Answer:-  To convert large scale data to small scale then explicit conversion will be required.

                  To Convert small scale to large scale then implicit (automatically) .

                  int to object:-  implicit   //boxing
                  Object to int :-  explict  //unboxing


  class A
{
    public static void main(String scs[])
    {
          int num=10;
          int num2;
          Object o;
          o=num;
          System.out.println(o);
        num2=(int)o; //explict
       System.out.println(num2);
     
       

    }

}



ASSIGNMENT:-

WAP to calculate electricity bill where unit price,total consumption ,load will be entered by the user?

WAP to calculate salary of emp where ta,da,comm,pf,numberofleave will be entered by the user?

WAP to check which type of data is entered by the user?

WAP to add without + symbol?






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