Operators

Operators

Operators are used to perform some operations.
Operators are special symbols that works with variables and constants in java. These symbols performs specific operation and gave result accordingly.

Operators work with Operands.
For Eg: a + b;
Here a, b are Operands to which operation is to be performed,
         + is Operator symbol.

To work with operators 3 things must be noticed before using them i.e.

1. Use of operator.
2. Type of operand you are using.
3. Result of operation.

Unary Operators : These type of operators required only one operand.
For e:. +, -, ++, --

Binary Operators : These type of operators required two operands to perform some operation.
For eg: +, -, *, =, >, <, && etc.

Ternary Operators : These type of operators required three operands to perform some operation.
For eg: :?

Arithmetic Operators : 
         Arithmetic operators are used to perform arithmetic operations like addition, subtraction etc.
Result of Arithmetic operation will always be of int type or wider than int type.
There are 2 types of  Arithmetic Operators :

• Binary Arithmetic Operators (+, -, *, /, %)
• Unary Arithmetic Operators (+, -): To use two unary operators together, it is mandatory to use space or parenthesis between them.Otherwise compiler will take them as Increment/Decrement Operators.

+ and - operators used as unary Operators have different meanings in both of them- In binary they used to perform simple addition and subtraction whereas in unary - means negative value and + means positive value.
Operators works according to their precedence, higher precedence operator will perform first.
In arithmetic operators we have following precedence -

1.  +, - Unary Operators.
2.  %, /, * Multiplicative.
3.  +, - Additive.

String Concatenation: 
         To concatenate two values String concatenation is used where both or one of these values must be string value,only then this operation will be performed.
+ Operator is used to concatenate.
It is a binary operator.
In arithmetic + operators adding two values like 5+10 it gave result in 15. But in String + operator will concatenate them for eg: 5 + 10 gave result as 510.
But one condition is applied to them i.e. at least one value must be a string value, only then compiler will get to know that they are string values and needed to be concatenate.
For eg:
          int a = 5;
          String s1 = "6";
          String s2 = a + s1;
Result will be 56

• It is also used to convert a in type into String type. But for this an empty string is concatenated with value.

For eg:
         int a = 10;
         String s = a + "";  OR  String s = "" + a;
With empty string compiler will assumed both values as string and concatenate them as we done previously.

• + Operator in string also helps in reducing the code. Like to print a message.

For eg:
         int i = 5;
         int j = 9;
         int k = i + j;
         String str = "The Sum of "+i+" and "+j+" is "+k;
         System.out.print(str);
Thus it used to formatting the message.

Assignment Operator: 

• It is a binary operator.
• It is used to assign a value to a variable. Which assigns the value of its right operand to its left operand.
• Value can also be a variable or expression.
• = operator is used for assignment.
• For assigning, value should be of same type or compatible type.

        Op1 = Op2
Op1 should always be a Variable.
Op2 can be Value/ Variable/ Exp.