Operator Concept in Java

Operator Concept in Java:-

It is a special identifier of Java which has defined as a predefined method in java library. It is used to perform a different type of operation using operand.

The operand can be defined as a variable, constant, and literals in the program.

Object operator +()
{

}
Object operator -()
{

}


we can not redefine operator definition in Java because the operator method is read-only.

hence java not support operator overloading concept.

Type of Operator:-

1 Unary:-    It will work using a single operand

1.1 Increment:-     It is used to increase the value by one

1.1.1 Pre:-     First Increase value then perform other operations.

      ++identifier

1.1.2 Post:-    First perform other operations then increase value.
       identifier++

int a=2,b;
b=a++;    //b=2,a=3

int a=3,b;
b=++a; //4,4


int a=2,b;
b = a++ + a++ + a++;
#9      2        3        4     5   a=5,b=9



1.2 Decrement
1.2.1   Pre decrement:-  --identifier  first decrease than other operation
1.2.2   Post decrement:-  identifier-- first assign then decrease

Program of Increment and Decrement:-
class Incrdemo
{
 public static void main(String args[])
 {
    int a=2,b;
    b = --a - a-- + a++ + a-- + ++a - --a + a++; //1,4,1,2,1,2,1,2,1,2
   // b =  1 -  1   0         1        1     0     0   1

    System.out.println("a=" +  a +  " b= "+ b);
}

}

2 Binary Operator:-

It is used to perform a binary operation using a minimum of two operands.

1 Arithmetic :-  +,-,*,/,%

2 Conditional :-  <,>,<=,>=

3 Comparison:-  ==,!=,equals()

==       it is used to value type comparison
int a=2;
int b=2;
a==b
equals():-  it is used to compare Object because.
it will return Object data using address than compare.

String s = new String("hello");

String s1= new String("hello");

s==s1 ;//false   xyza123==klmn123

s.equals(s1) //true   hello==hello

4.  Assignment Operator:-
 4.1.1   =  it is used to assign a value into a variable

           +=   a+=2  or a=a+2

           -=    a-=5  or a=a-5

           *=    a*=7  or a=a+7 

            /=   a/=3    or a=a/3

           %=  a%=5  or a=a%5
         

5 Logical Operator:-

    &&    it will return true when all condition will be true

    ||        it will return true when anyone condition will true

    !        it is just opposite of the true and false condition



3 Ternary:-

It is used to check the condition using a single-line statement. Ternary means combination of three operators,(conditional operator or comparison, ?, :)

Normal:-
var = (condition)?true:false

Nested Ternary Statement

var = (condition)?((condition)?true:false):((condition)
?true:false);


Limitation of Ternary Operator?

1) We can write only a single-line statement when a condition will be true or false means we can not write a block-level statement.

2)  for complex program ternary statement will be complex.


these problems have been resolved by If--else statement.

Example of Ternary Operator:-

class CheckGreater

{

   public static void main(String args[])

   {

        int a=50,b=300;

        String s = (a>b)?"a is greater":"b is greater";

        System.out.println(s);

   } 

}

WAP to check the greatest number?

Solution:-

class Greatest

{

    public static void main(String args[])

    {

       int a=1000,b=2000,c=300;

       String s = (a>b && a>c)? "a is greatest":(b>c?"b is greatest":"c is 

greatest");

       System.out.println(s);

       

       }

}

WAP to check leap year?
WAP to check vowel, consonant?
WAP to display "YES","NO","CANCEL" when user press y.n and c?

The solution of this program

import java.util.Scanner;
class Greatest
{
    public static void main(String args[])
    {
         Scanner sc = new Scanner(System.in);
         char ch;
         System.out.println("enter char");
         ch = sc.next().charAt(0);
         String s = (ch=='y')?"YES":(ch=='n'?"NO":(ch=='c'?"cancel":"press y

,n and c"));
         System.out.println("\""+s+"\"");


     }


}