4.
Operators:
Operator is a syntax, it will perform a particular operator over the
provided operands.
To prepare java application, java has provided the following list of
operators.
1.
Arithmetic operator :
+,-,*,/,%,++,--,…………
2.
Assignment operators :
=,+=,-=,*=, /=,%=
3.
Comparison operators:
==, !=, <, >, <=, =>,……..
4.
Logical Boolean operator :
&, |, ^
5.
Logical Bitwise operator:
&, |,^,<<,>>………………
6.
Ternary operator:
Exper? Exp2: Exp3;
7.
Short-circuit operators :
&&,||
Ex:-
class Test
{
public static void
main(String[] args)
{
int a=10;
System.out.println(a);
System.out.println(a++);
System.out.println(++a);
System.out.println(a--);
System.out.println(--a);
System.out.println(a);
}
}
Output :
10
10
12
12
10
10
Ex1:-
class Test
{
public static void
main(String[] args)
{
int a=7;
System.out.println(++a+--a);
}
}
Output :
>>int a=7;
++a + --a
8+ 7
15
Ex2:-
class Test
{
public static void
main(String[] args)
{
int a=6;
System.out.println(a++*--a+a--*++a);
}
}
Output:
>>6*6+6*6
>>36+36
>>72
Ex 3:
class Test
{
public static void
main(String[] args)
{
int a=5;
System.out.println((++a-a--)+(--a+a++)*(++a-++a)+(--a+--a));
}
}
Output:
>>(6-6)+(4+4)*(6-7)+(6+5)
>>(0)+(8)*(-1)+(11)
>>0-8+11
>>-8+11
>>3
Date :02- august-2016
Boolean operators
Boolean truth table
|
A
|
B
|
A&B
|
A|B
|
A^B
|
|
T
(1)
|
T
(1)
|
T
(1)
|
T
(1)
|
F
(0)
|
|
T
(1)
|
F
(0)
|
F
(0)
|
T
(1)
|
T
(1)
|
|
F
(0)
|
T
(1)
|
F
(0)
|
T
(1)
|
T
(1)
|
|
F
(0)
|
F
(0)
|
F
(0)
|
F
(0)
|
F
(0)
|
EX:-
class Test
{
public static void
main(String[] args)
{
boolean
b1=true;
boolean
b2=false;
System.out.println(b1&b1);
//true
System.out.println(b1&b2);//false
System.out.println(b2&b1);//false
System.out.println(b2&b2);//false
System.out.println(b1|b1);
//true
System.out.println(b1|b2);//true
System.out.println(b2|b1);//true
System.out.println(b2|b2);//false
System.out.println(b1^b1);
//false
System.out.println(b1^b2);//true
System.out.println(b2^b1);//true
System.out.println(b2^b2);//false
}
}
Bitwise operators
Ex:-
class Test
{
public static void
main(String[] args)
{
int a=10;
int b=2;
System.out.println(a&b);
System.out.println(a|b);
System.out.println(a^b);
System.out.println(a<<b);
System.out.println(a>>b);
}
}
Output:
2
10
8
40
2
Explanation
>>int a=10;-----à1010
>>int b=2;-------à0010
-----------------------------------
>>a&b-à10&2à0010=>2
------------------------------------
>>a|bà10|2à 1010=>10
------------------------------------
>>a^bà10^2à 1000=>8
------------------------------------
>>a<<bà10<<2àexpression
8 bit operators
00001010à10
<< 00101000à40
>>a>>bà10>>2àexpression
8 bit operators
00001010à10
> > 00000010 à2
Date :03- august-2016
Short-circuit operators:-
The main intention of logical-OR operator, if the first
operator, value is “true “ then i6 is
not required to check second operator value, directly, we can predict the
result of the overall “OR” express is “true”.
In case of ‘|’ operator, even through first operand value
the only JVM will predict the overall ‘OR’ operator expression, in the case
evaluation second operand expression is unnecessary, it will increases
application time and it will reduce application performance.
In case of || operator, if first operator value is “true”
then JVM will not check second operand value, directly, JVM will predict the
overall ‘OR” expression overall is true. In this case, JVM is not executing
second operand value explicitly, it will reduce application execution time and
it will improve application performance.
Ex:-
class Test
{
public
static void main(String[] args)
{
int
a=10;
int
b=10;
if((a++==10)|(b++==10))
{
System.out.println(a);
System.out.println(b);
}
int
c=10;
int
d=10;
if
((c++==10)||(d++==10))
{
System.out.println(c);
System.out.println(d);
}
}
}
Output :
11
11
11
10
& Vs
&&
In case of “logical AND” operator, if the first operator
value is “false” then it is not required to check second operator value,
directly we can get “false” as result from the overall “AND” operation result.
In case of “A” operator, even through first operand value is
“false” still JVM will go to second operand value and JVM will get the overall
expression result on the basis of first operand and second operator values, in
this case evaluation second operand expression is unnecessary, it will increase
application execution time and it will reduce application performance.
In case of “&” operator, if first operand value is
“false” then JVM will not evaluation second operand value directly, JVM will
get the overall AND Expression result that is “false” , here JVM is not
evaluating second operand expression unnecessary, it will reduce application
execution time and if will improve application performance.
Ex:-
class Test
{
public
static void main(String[] args)
{
int
a=10;
int
b=10;
if((a++!=10)&(b++!=10))
{
}
System.out.println(a);
System.out.println(b);
int
c=10;
int
d=10;
if
((c++!=10)&&(d++!=10))
{
}
System.out.println(c);
System.out.println(d);
}
}
Output :-
11
11
11
10
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