2. Java provides a rich set of operators to manipulate
variables. We can divide all the Java operators into the
following groups:
• Assignment Operator
•Arithmetic Operators
•Unary Operators
• Equality and Relational Operators
•Conditional (Logical) Operators
•Bitwise and Bit Shift Operators
3. (1) Assignment Operator
Simple Assignment Operator
Syntax of using the assignment operator is:
<variable> = <expression>;
Compound Assignment Operator
Syntax of using the compound assignment operator is:
operand operation= operand
4. Compound assignment operators :
Operator Example Equivalent Expression
+= x += y; x = (x + y);
-= x -= y; x = (x - y);
*= x *= y; x = (x * y);
/= x /= y; x = (x / y);
%= x %= y; x = (x % y);
&= x &= y; x = (x & y);
|= x != y; x = (x ! y);
^= x ^= y; x = (x ^ y);
<<= x <<= y; x = (x << y);
>>= x >>= y; x = (x >> y);
>>>= x >>>= y; x = (x >>> y);
5. (2) Arithmetic Operators
The symbols of arithmetic operators are given in a table:
Symbol Name of the Operator Example
+ Additive Operator n = n + 1;
- Subtraction Operator n = n - 1;
* Multiplication Operator n = n * 1;
/ Division Operator n = n / 1;
% Remainder Operator n = n % 1;
The "+" operator can also be used to concatenate (to join) the two strings
together.
For example:
String str1 = "Concatenation of the first";
String str2 = "and second String";
String result = str1 + str2;
6. (3) Unary Operators
There are different types of unary operators :
+ Unary plus operator indicates positive value (however, numbers
are positive without this)
Ex : int number = +1;
- Unary minus operator negates an expression
Ex : number = - number;
++ Increment operator increments a value by 1
Ex : number = ++ number;
-- Decrement operator decrements a value by 1
Ex : number = -- number;
! Logical compliment operator inverts a boolean value
7. (4) Equality and Relational Operators
Symbol Name of the Operator Example
== Equal to a==b
!= Not equal to a!=b
> Greater than a>b
< Less than a<b
>= Greater than or equal to a>=b
<= Less than or equal to a>=b
8. (5) Conditional (Logical) Operators
Symbol Name of the Operator
& AND
&& Conditional-AND
| OR
|| Conditional-OR
! NOT
?: Ternary (shorthand for if-then-else statement)
9. ternary ("?:") operator
Java supports another conditional operator that is known as the ternary operator
"?:" and basically is used for an if-then-else as shorthand as
boolean expression ? operand1 : operand2;
If we analyze this diagram then we find that, operand1 is returned, if
the expression is true; otherwise operand2 is returned in case of false
expression.
10. Lets have an example implementing some Logical operators:
class ConditionalOperator
{
public static void main(String[] args)
{
int x = 5;
int y = 10, result=0;
boolean bl = true;
if((x == 5) && (x < y))
System.out.println("value of x is "+x);
if((x == y) || (y > 1))
System.out.println("value of y is greater than the value of x");
result = bl ? x : y;
System.out.println("The returned value is "+result);
}
}
11. Output
value of x is 5 is 5
value of y is greater than the value of x lue of y is greater than the value of x
The returned value is 5
12. (6) Bitwise and Bit Shift Operators
. There are different types of bitwise and bit shift operators available in
the Java language summarized in the table.
Symbol Name of the Operator Example
~ Unary bitwise complement ~op2
& Bitwise AND op1 & op2
| Bitwise inclusive OR op1 | op2
^ Bitwise exclusive OR op1 ^ op2
<< Signed left shift op1 << op2
>> Signed right sift op1 >> op2
>>> Unsigned right shift op1 >>> op2
13. I. Unary Bitwise Complement ("~") :
Lets use the table to understand bitwise complement
operation :
Operand Result
0 1
1 0
1 0
0 1
II. Bitwise AND (&) :
Lets understand the AND operations using truth table:
(AND)
A B Result
0 0 0
1 0 0
0 1 0
1 1 1
14. III. Bitwise inclusive OR ( | ) :
Lets understand the inclusive OR operations using truth
table:
(OR)
A B Result
0 0 0
1 0 1
0 1 1
1 1 1
IV. Bitwise exclusive OR (^) :
Lets understand the exclusive OR operations using truth
table:
A B Result
0 0 0
1 0 1
0 1 1
1 1 0
15. Bit Shifts Operators:
I. Signed Left Shift ("<<") :
This diagram shows that, all bits of the upper position were shifted to the left by
the distance of 1; and the Zero was shifted to the right most position. Thus the
result is returned as 11100.
Another expression "2<<2"; shifts all bits of the number 2 to the left placing a
zero to the right for each blank place. Thus the value 0010 becomes 1000 or 8 in
decimal.
16. II. Signed Right Shift (">>") :
This diagram shows that, all bits of the upper position were shifted to the right
distance specified by 1; Since the sign bit of this number indicates it as a positive
number so the 0 is shifted to the right most position. Thus the result is returned as
00011 or 3 in decimal.
Another expression "2>>2"; shifts all bits of the number 2 to the right placing a
zero to the left for each blank place. Thus the value 0010 becomes 0000 or 0 in
decimal.
17. III. Unsigned Right Shift (">>>") :
For example, the expression "14>>>2"; shifts all bits of the
number 14 to the right placing a zero to the left for each blank
place Thus the value 1110 becomes 0011 or 3 in decimal.
19. Lets see an example that evaluates an arithmetic
expression according to the precedence order.
class PrecedenceDemo
{
public static void main(String[] args)
{
int a = 6;
int b = 5;
int c = 10;
float rs = 0;
rs = a + (++b)* ((c / a)* b);
System.out.println("The result is:" + rs);
}
}
20. The expression "a+(++b)*((c/a)*b)" is evaluated from right
to left. Its evaluation order depends upon the precedence order of
the operators. It is shown below:
(++b) a + (++b)*((c/a)*b)
(c/a) a+ (++b)*((c/a)*b)
(c/a)*b a + (++b)*((c/a)* b)
(++b)*((c/a)*b) a + (++b)*((c/a)* b)
a+(++b)*((c/a)*b) a+(++b)*((c/a)*b)
Output
The result is:42.0
