Pj01 4-operators and control flow

Basic Java Programming
Sasidhara Marrapu

Java Operators
 Operators  Lab Problem
 Home Work

Operators:
Arithmetic Operators
Relational Operators
Assignment Operators
Logical Operators
Bitwise Operators
Misc Operators

Mathematical/Arithmetic Operators
Name Meaning Example Result
+ Addition 34 + 1 35
- Subtraction 34.0 – 0.1 33.9
* Multiplication 300 * 30 9000
/ Division 1.0 / 2.0 0.5
% Remainder 20 % 3 2

Mathematical/Arithmetic Operators
public class Example {
public static void main(String[] args) {
int j, k, p, q, r, s, t;
j = 5;
k = 2;
p = j + k;
q = j - k;
r = j * k;
s = j / k;
t = j % k;
System.out.println("p = " + p);
System.out.println("q = " + q);
System.out.println("r = " + r);
System.out.println("s = " + s);
System.out.println("t = " + t);
}
} > java Example
p = 7
q = 3
r = 10
s = 2
t = 1
>

Relational Operators
Primitives
• Greater Than >
• Less Than <
• Greater Than or Equal >=
• Less Than or Equal <=
Primitives or Object References
• Equal (Equivalent) ==
• Not Equal !=
The Result is Always true or false

Relational Operator Examples
int p =2; int q = 2; int r = 3;
Integer i = new Integer(10);
Integer j = new Integer(10);
System.out.println("p < r " + (p < r));
System.out.println("p > r " + (p > r));
System.out.println("p == q " + (p == q));
System.out.println("p != q " + (p != q));
System.out.println("i == j " + (i == j));
System.out.println("i != j " + (i != j));
}
} > java Example
p < r true
p > r false
p == q true
p != q false
i == j false
i != j true
>

Assignment Operator (=)
lvalue = rvalue;
• Take the value of the rvalue and
store it in the lvalue.
• The rvalue is any constant,
variable or expression.
• The lvalue is named variable.
w = 10;
x = w;
z = (x - 2)/(2 + 2);

Assignment Operator (=) and
Classes
Date x = new Date();
Date y = new Date();
x = y;

Shorthand Operators
Operator Common Shorthand
+= a = a + b; a += b;
-= a = a - b; a -= b;
*= a = a * b; a *= b;
/= a = a / b; a /= b;
%= a = a % b; a %= b;

Shorthand Operators
int j, p, q, r, s, t;
j = 5;
p = 1; q = 2; r = 3; s = 4; t = 5;
p += j;
q -= j;
r *= j;
s /= j;
t %= j;
System.out.println("t = " + t);
}
}
> java Example
p = 6
q = -3
r = 15
s = 0
t = 0
>

Shorthand Increment and
Decrement ++ and --
Common Shorthand
a = a + 1; a++; or ++a;
a = a - 1; a--; or --a;

Increment and Decrement
> java example
p = 6
q = 6
j = 7
r = 6
s = 6
>
int j, p, q, r, s;
j = 5;
p = ++j; // j = j + 1; p = j;
q = j++; // q = j; j = j + 1;
System.out.println("j = " + j);
r = --j; // j = j -1; r = j;
s = j--; // s = j; j = j - 1;
}
}

Logical Operators (boolean)
 Logical AND &&
 Logical OR ||
 Logical NOT !

Logical (&&) Operator Examples
boolean t = true;
boolean f = false;
System.out.println("f && f " + (f && f));
System.out.println("f && t " + (f && t));
System.out.println("t && f " + (t && f));
System.out.println("t && t " + (t && t));
}
} > java Example
f && f false
f && t false
t && f false
t && t true
>

Logical (||) Operator Examples
boolean t = true;
boolean f = false;
System.out.println("f || f " + (f || f));
System.out.println("f || t " + (f || t));
System.out.println("t || f " + (t || f));
System.out.println("t || t " + (t || t));
}
}
> java Example
f || f false
f || t true
t || f true
t || t true
>

Logical (!) Operator Examples
boolean t = true;
boolean f = false;
System.out.println("!f " + !f);
System.out.println("!t " + !t);
}
} > java Example
!f true
!t false
>

Logical Operator Examples
Short Circuiting with &&
boolean b;
int j, k;
j = 0; k = 0;
b = ( j++ == k ) && ( j == ++k );
System.out.println("b, j, k " + b + ", " + j + ", " + k);
j = 0; k = 0;
b = ( j++ != k ) && ( j == ++k );
}
}
> java Example
b, j, k true 1, 1
> java Example
b, j, k true 1, 1
b, j, k false 1, 0
>

Logical Operator Examples
Short Circuiting with ||
boolean b;
int j, k;
j = 0; k = 0;
b = ( j++ == k ) || ( j == ++k );
j = 0; k = 0;
b = ( j++ != k ) || ( j == ++k );
}
}
> java Example
b, j, k true 1, 0
> java Example
b, j, k true 1, 0
b, j, k true 1, 1
>

Bitwise Operators
• AND &
• OR |
• XOR ^
• NOT ~

Bitwise Operator Examples
class BitwiseOR {
int number1 = 12, number2 = 25, result;
result = number1 | number2;
System.out.println(result);
}
}
29

29
12 = 00001100 (In Binary)
25 = 00011001 (In Binary)
Bitwise OR Operation of 12 and 25
00001100
| 00011001
________
00011101 = 29 (In decimal)

int a = 10; // 00001010 = 10
int b = 12; // 00001100 = 12
int and, or, xor, na;
and = a & b; // 00001000 = 8
or = a | b; // 00001110 = 14
xor = a ^ b; // 00000110 = 6
na = ~a; // 11110101 = -11
System.out.println("and " + and);
System.out.println("or " + or);
System.out.println("xor " + xor);
System.out.println("na " + na);
}
} > java Example
and 8
or 14
xor 6
na -11
>

Ternary Operator
? :
If true this expression is
evaluated and becomes the
value entire expression.
Any expression that evaluates
to a boolean value.
If false this expression is
evaluated and becomes the
value entire expression.
boolean_expression ? expression_1 : expression_2

Ternary ( ? : ) Operator Examples
boolean t = true;
boolean f = false;
System.out.println("t?true:false "+(t ? true : false ));
System.out.println("t?1:2 "+(t ? 1 : 2 ));
System.out.println("f?true:false "+(f ? true : false ));
System.out.println("f?1:2 "+(f ? 1 : 2 ));
}
}
> java Example
t?true:false true
t?1:2 1
f?true:false false
f?1:2 2
>

String (+) Operator
String Concatenation
"Now is " + "the time."
"Now is the time."

String (+) Operator
Automatic Conversion to a String
If either expression_1
If either expression_1 or expression_2 evaluates
to a string the other will be converted to a string
if needed. The result will be their concatenation.
expression_1 + expression_2

String (+) Operator
Automatic Conversion with Primitives
"The number is " + 4
"The number is " + "4"
"The number is 4"

String (+) Operator
Automatic Conversion with Objects
"Today is " + new Date()
"Today is " + "Wed 27 22:12;26 CST 2000"
"Today is Wed 27 22:12;26 CST 2000"
"Today is " + new Date().toString()

Instance of Operator
• This operator is used only for object reference
variables.
• The operator checks whether the object is of a
particular type (class type or interface type).
instanceof operator is written as
( Object reference variable ) instanceof (class/interface type)

InstanceOf Examples
public static void main(String args[]) {
String name = "James";
// following will return true since name is type of String
boolean result = name instanceof String;
System.out.println( result );
}
}
> true

Operator Precedence
+ - ++ -- ! ~ ()
* / %
+ -
<< >> >>>
> < >= <= instanceof
== !=
& | ^
&& ||
?:
= (and += etc.)
Unary
Arithmetic
Shift
Comparison
Logical Bit
Boolean
Ternary
Assignment

Pj01 4-operators and control flow

More Related Content

What's hot (20)

Similar to Pj01 4-operators and control flow (20)

Recently uploaded (20)

Pj01 4-operators and control flow