Data Types and Arrays and Operators

 Data Types

The Primitive Types

Java defines eight primitive types of data:

·         Byte

·         Short

·         int

·         Long

·         char

·         float

·         double and

·         Boolean

The primitive types are also commonly referred to as simple types

These can be put in four groups

·                    Integers

o        This group includes byte, short, int, and long, which are for whole-valued signed numbers.

·                     Floating-point numbers

o        includes float and double, which represent numbers with fractional precision.

·                     Characters

o        includes char, which represents symbols in a character set, like letters and numbers.

·                     Boolean

o        includes Boolean, which is a special type for representing true/false values 

 

Integers

·         four integer types: byte, short, int, and long

·         All of these are signed, positive and negative values

Floating-Point Types

• Also known as real numbers
•   There are two kinds of floating-point types
•   float and double

Characters

·         used to store characters is char

·         Java char is a 16-bit type

·         The range of a char is 0 to 65,536

Booleans

• In Java, type boolean is  for logical values
• It can have only one of two possible values
• true or false
• It can be used in control statements

Arrays

·         An array is a group of like-typed variables that are referred to by a common name.

·         Arrays of any type can be created and may have one or more dimensions

·         A specific element in an array is accessed by its index

One-Dimensional Arrays

·                     The general form of a one-dimensional array declaration is

o        type var-name[ ];                            Eg:int month_days[];

·                     Allocating memory for arrays is done by new operator, and the general form is

o        array-var = new type[size];

o        Eg: month_days = new int[12];

§     month_days will refer to an array of 12 integers

·                     We can join both the declaration and allocation

o        type var-name[ ]= new type[size];

o        Eg:int month_days[] = new int[12];  

Program

Multidimensional Arrays

•          multidimensional arrays are actually arrays of arrays
•          the following declares a twodimensional array variable called twoD

o   int twoD[][] = new int[4][5];

o   This allocates a 4 by 5 array and assigns it to twoD

o   implemented as an array of arrays of int

program

Operators

Divided into the following four groups: 

• Arithmetic 
• Bitwise 
• Relational, and 
•  Logical

Arithmetic Operators

Are used in mathematical expressions in the same way that they are used in algebra

The Bitwise Operators

These operators act upon the individual bits of their operands

Relational Operators

·         determine the relationship that one operand has to the other

·         they determine equality and ordering

Logical Operators

·         AND- &&

·         OR- ||

·         NOT- !

Assignment Operator

single equal sign, =

The ? Operator

•          a special ternary (three-way) operator
•              general form:

exp1 ? exp2 : exp3

Here, exp1 can be any expression that evaluates to a boolean value. If exp1 is true, then exp2 is evaluated; otherwise, exp3 is evaluated

Program

for more click on to the following link:

       https://youtu.be/yKf5AHvqh-M