Quick introduction to Java Programming language - Part 1

Operator is a symbol that is used to do some specific operations.Types of operators in java:

• Arthematic Operators
• Relational Operators
• Logical Operators
• Assignment Operators
• Comparison Operators
• Unary Operators

Arthematic Operators:

These operators are used to perform athematic operations like addition, substraction, division etc.We will get the number as result from this operations.

Here “+” symbols is also used for concatenation purpose.If any operand is string then “+” acts as a concatenation.

Example:

10+30 = 40
"abc"+10 ="abc10"
"ab”+"cd"="abcd"

Example:

public class AddNumbs {
 public static void main(String[] args){
   int a =10;
   int b = 8;
   int sum=a+b;
   System.out.println("the sum of two number is:" + sum); //here, “+” is acting as concatenation
 }
}

Relational Operators:

These operators is used to compare the relation between two variables. We will get the boolean values(true/false) as result from this operation.

Relation Operators are:

Example:

public class Example {
 public static void main(String[] args){
   int a =10;
   int b = 8;
   System.out.println( a == b ); // returns false
   System.out.println( a !=  b ); // returns true
 }
}

Logical Operators: 

These operators takes two boolean inputs and we will get one boolean output.Logical Operators are:

Example:

public class Example {
 public static void main(String[] args){
   int a =10;
   int b = 8;
   System.out.println( (a >= 9) && (b <= 10)); // returns true
   System.out.println( (a >  b) || (b> 10) ); // returns true
 }
}

Assignment Operators: 

These operator is used to assign the values.Assignment Operators are:

Example:

public class AddNumbs {
 public static void main(String[] args){
   int a = 0;
   int b = 8;
   a+=b; // a now have evalue 8
   System.out.println("Value of a is :" + a); 
 }
}

Unary Opertors:

These operators will work for only one operand.

Types of Unary Operators:

• Increment ++;
• Decrement --;

Example: Increment ++

public class AddNumbs {
 public static void main(String[] args){
   int a = 0;
   a++; 
   System.out.println("Value of a is :" + a);  // 1
 }
}

Example: Decrement --

public class AddNumbs {
 public static void main(String[] args){
   int a = 1;
   a--; 
   System.out.println("Value of a is :" + a);  // 0
 }
}

Bitwise Operators:

Java provides bitwise operators and bit shift operations on integral types.

Bitwise Binary Operations:

Four bit operators in Java.

• ~ - Unary complement
• & - Bitwise and
• ^ - Bitwise exclusive or
• | - Bitwise inclusive or
• <<-Binary Left Shift Operator
• >>-Binary Right Shift Operator
• >>>-Shift right zero fill operator

Examples:

1010 & 0101 = 0000
1100 & 0110 = 0100

1010 | 0101 = 1111
1100 | 0110 = 1110

~1111 = 0000
~0011 = 1100

1010 ^ 0101 = 1111
1100 ^ 0110 = 1010

Conditional Operator:

are ternary operators which has three operands.

Syntax:
(Expression) ? (true) : (false);

Example:

int big = (a>b) ? a:b

Main method example

.....

public static void main(String args[])
{
  int a=100;
  int b = 20;
  int big=(a>b)?a:b;
  System.out.println(“big value:”+big); //output: big value:100
}
.....

Instanceof Operator:

These operatorused to check the object is of a particular type or not.This operator returnsBoolean value true/false.

Syntax:

(Object reference variable) instanceof (class type)

Example:

public class Test{
 public static void main(String args[]){
 String subject="Maths";
 boolean result =subjectinstanceofString;//comparing the values
 System.out.println( result ); // Output: True
 }
}

In next chapter we will explore looping statements