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COMPUTER SOFTWARE APPLICATION - CITS

Java Numbers

Numbers
Primitive number types are divided into two groups:
Integer types stores whole numbers, positive or negative (such as 123 or -456), without decimalsValid types are
byte, short, int and long. Which type you should use, depends on the numeric value.
Floating point types represents numbers with a fractional part, containing one or more decimals. There are two
types: float and double
Integer Types
Byte
The byte data type can store whole numbers from -128 to 127. This can be used instead of int or other integer
types to save memory when you are certain that the value will be within -128 and 127:
Example
byte myNum = 100;
System.out.println(myNum);
Short
The short data type can store whole numbers from -32768 to 32767:
Example
short myNum = 5000;
System.out.println(myNum);
Int
The int data type can store whole numbers from -2147483648 to 2147483647. In general, and in our tutorial, the
int data type is the preferred data type when we create variables with a numeric value.
Example
int myNum = 100000;
System.out.println(myNum);
Long
The long data type can store whole numbers from -9223372036854775808 to 9223372036854775807. This is
used when int is not large enough to store the value. Note that you should end the value with an “L”:
Example
long myNum = 15000000000L;
System.out.println(myNum);
Floating Point Types
You should use a floating point type whenever you need a number with a decimal, such as 9.99 or 3.14515.
The float and double data types can store fractional numbers. Note that you should end the value with an “f” for
floats and “d” for doubles:
Example
float myNum = 5.75f;
System.out.println(myNum);
Double Example
Example
double myNum = 19.99d;
System.out.println(myNum);

Java String
In Java, string is basically an object that represents sequence of char values. An array of characters works same
as Java string
For example:

1 char[] ch={‘j’,’a’,’v’,’a’,’t’,’p’,’o’,’i’,’n’,’t’};

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CITS : IT&ITES - Computer Software Application - Lesson 85 - 93