Java basic datatypes
- 2. Basic Datatypes • Datatypes: int, String, float, short, byte, long, double, Boolean. • Datatypes used to create a variables. • Variables are reserved memory location to store values. • When we create variables, we receive some space in memory. 96.6 200 P1713 Moon name regno amountpercentage
- 3. Basic Datatypes • By assigning different values to variables, we can store different datatypes. • 2 datatypes: Primitive, Reference/Object 96.6 200 P1713 Moon name regno amountpercentage datatype variable_name = value; datatype variable_name; variable_name = value;
- 4. Basic Datatypes – Primitive Data Types • Primitive datatypes are predefined by the language and named by a keywords. • There are 8 primitive datatypes supported by java. 1. byte 2. short 3. int 4. long 5. float 6. double 7. boolean 8. char
- 5. Primitive Data Types ( byte) • 8 bit signed 2’s complement integer. (-128) (0) • Used to save space in large array. • 4 times smaller than int. byte a = 68; (127) byte a = -128;
- 6. Primitive Data Types ( short) • 16 bit signed 2’s complement integer. (-32,768) (0) (32,767) • Used to save space in large array. • 2 times smaller than int. short a = 1000;short a = -1000;
- 7. Primitive Data Types ( int) • 32 bit signed 2’s complement integer. (-2,147,483,648) (0) (2,147,483,647) • Default datatypes for integral values. • There is a concern about memory. int a = 1236542;int a = -123648;
- 8. Primitive Data Types ( long) • 64 bit signed 2’s complement integer. • This type is used when a wider range than int is need long a = 10486L;long a = -100L; L is maximum duration of 32 10486L = -9,223,372,036,854,775,808 to 0L to -9,223,372,036,854,775,807
- 9. Primitive Data Types ( float) • single-precision 32-bit IEEE 754 floating point. • Used to save memory in large arrays of floating point values. • Never used for precise values such as currency. float a = 234.5f;0.0f
- 10. Primitive Data Types ( double) • double-precision 32-bit IEEE 754 floating point. • generally used as the default data type for decimal values. • Never used for precise values such as currency. double a = 234.5;0.0d
- 11. Primitive Data Types ( boolean) • It represents one bit of information. • 2 possible values: true and false. • This data type is used for simple flags that track true/false conditions. • Default value: false. boolean a = true; asign a=10 asign b=20 a=b //false asign b=b-a a=b //true
- 12. Primitive Data Types ( char) • 16 bit Unicode character. • Char data type is used to store any character. char a = ‘A’;‘u0000’ (0) ‘uffff’ (65,535 inclusive)
- 13. Basic Datatypes – Reference Data Types • Reference variables are created using defined constructors of the classes. • They are used to access objects. • Class objects and various type of array variables come under reference datatype • Default value is null. Animal a=new Animal(); Animal a=new Animal(0,’asdf’);
- 14. Basic Datatypes Notation Character represented n Newline (0x0a) r Carriage return (0x0d) f Formfeed (0x0c) b Backspace (0x08) s Space (0x20) t tab " Double quote ' Single quote backslash ddd Octal character (ddd) uxxxx Hexadecimal UNICODE character (xxxx) • Few special escape sequences for String and char literals