The document discusses various Java data types including primitive types like int, float, double, and reference types like arrays and classes. It covers numeric type sizes and representations, type conversions, operators, statements, and arrays. Examples are provided for literals, identifiers, escape sequences, operators, conditional and loop statements, and getting user input.

1. DATA TYPES AND OPERATORS
AND STATEMENTS

2. Data types
2
Prof. Ashish Bhatia

3. Byte Ordering
3
JAVA
x86 and
x64
Prof. Ashish Bhatia

4. Floating Points - float
4
 Float [ 8byte = 64 bits]
 123.45 ? What is exponent and Significand
 31 – Sign Bit [ 1 bit ]
 23-30 – Exponent Field [ 8 bit ]
 0-22 - Significand [23 bit]
Prof. Ashish Bhatia

5. Floating Points
5
 Float [ 4byte = 32 bits]
Bits 30-23 Bits 0-22 Significand
Exponent
0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bits 30-23 Bits 0-22 Significand
Exponent
1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bits 30-23 Bits 0-22 Significand
Exponent
1 1 1 1 1 1 1 1 1 Any Non – zero value
Prof. Ashish Bhatia

6. Floating Points - double
6
Bits 62-52 Bits 51-0 Significand
Exponent
0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bits 62-52 Bits 51-0 Significand
Exponent
1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bits 62-52 Bits 51-0 Significand
Exponent
1 1 1 1 1 1 1 1 1 Any non-zero value
Prof. Ashish Bhatia

7. Super Type and Sub Type Relations
7
double
float
long
int
short char
byte
Prof. Ashish Bhatia

8. Using Literals
8
 Use l or L for long values else everything is int.
 Use f or F for Float values else everything is double.
 For Octal use 0
 For Hex use 0x or 0X
 used for special characters
 ‘n’ = New Line
 ‘t’ = Tab
 ‘017’ = Character constant
Prof. Ashish Bhatia

9. Legal Identifiers
9
 Must start with a letter, a currency character ($), or
a connecting character such as the underscore ( _ ).
Identifiers cannot start with a number!
 After the first character, identifiers can contain any
combination of letters, currency characters,
connecting characters, or numbers.
 In practice, there is no limit to the number of
characters an identifier can contain.
 Identifiers in Java are case-sensitive; foo and FOO
are two different identifiers.
Prof. Ashish Bhatia

10. Example
10
 int _a;
 int $c;
 int ______2_w;
 int _$;
 int this_is_a_very_detailed_name_for_an_;
 int :b;
 int -d;
 int e#;
 int .f;
 int 7g;
Prof. Ashish Bhatia

11. Unicode Escape in Java
11
 ufour hex number
 u0A85
Prof. Ashish Bhatia

12. Reference Datatypes
12
 Arrays
 Classes
 Interface
 Enum
 Annotation
Prof. Ashish Bhatia

13. Operators
13
 Arithmetic Operators
+ - * / %
 Conversion
 Widening
 Sub type to super type
 Narrowing
 Super Type to sub type
 Mixed Conversion
Prof. Ashish Bhatia

14. Operators
14
 Unary + and –
 String Concatenation
Prof. Ashish Bhatia

15. Operator
15
 Relational Operator
 < > <= >= == !=
 Logical Operator
 & | ^ ! && ||
 Bitwise Operator
 & | ^ ~ << >> >>>
 Increment and Decrement Operator [ ++ , -- ]
 Conditional Operator (? : )
 Assignment Operator
 instanceof
 new
Prof. Ashish Bhatia

16. Example
16
 int a = 60; /* 60 = 0011 1100 */
 int c = a << 2; /* 240 = 1111 0000 */
 int c = a >> 2; /* 15 = 1111 */
 int c = a >>> 2; /* 215 = 0000 1111 */
 What is int a = -60?
Prof. Ashish Bhatia

17. Statements
17
 Conditional
 if, if-else, switch-case
 Loop
 for, while, do-while
 break, continue, return
 Labeled break and continue
Prof. Ashish Bhatia

18. Brain Teasing Exercise
18
 x*=2+5
 boolean b = 100 > 99;
 5.0 == 5L
 if(x=0) {}
 if(b){}
 if(5 && 6) {}
 int x = 1;
int y=++x; // x++
System.out.println(y);
Prof. Ashish Bhatia

19. Output
19
 class Test{
public static void main(String[] args) {
int i = 42;
String s =
(i<40)?"life":(i>50)?"universe":"everyth
ing";
System.out.println(s);
}
}
Prof. Ashish Bhatia

20. Output
20
String s = "";
boolean b1 = true;
boolean b2 = false;
if((b2 = false) | (21%5) > 2) s += "x";
if(b1 || (b2 = true)) s += "y";
if(b2 == true) s += "z";
System.out.println(s);
Prof. Ashish Bhatia

21. More on Arrays
21
 int [] array; // recommended
 int array[];
 int [5] array; // ERROR
 Declaring an Array
 Constructing an Array
 int array[] = new Array[]
 int array[] = {1,2,3}
 int z[] = new int[] {1,2,3}
 int z[] = new int[3] {1,2,3}
Prof. Ashish Bhatia

22. Getting user input
22
import java.util.Scanner;
class Scan
{
public static void main(String args[])
{
Scanner s = new Scanner(System.in);
int x = s.nextInt();
System.out.println(x);
x = s.nextInt();
System.out.println(x);
}
}
Prof. Ashish Bhatia