JAVA : Data Type

Integers:

It includes whole valued signed numbers which are as follow.

Byte- Whose width is 8 and it ranges from -128 to 127. It is the smallest integer type. It is useful  when user is dealing with stream or flowing data from a network or a file.

Declaration of two byte variables called x and y is as follow

Byte x, y;

Short- The width of this type of integer is 16 and it ranges from -32,768 to 32,767. It is the least commonly used data type in java.

Declaration:

Short a;
Short b;

Int- The width of this type of integer is 32 and it ranges from -2,147,483,648 to 2,147,483,647. It is more efficient as compared to byte and short. It is commonly used to control loops and indexed arrays.

Declaration:

Int a;

Long-  The width of this type of integer is 64 and it ranges from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807. This is used for those values which are large enough that the integer cannot handle them.

Declaration:
Int light speed;
Long days;
Long second;
Seconds = days *24 *60*60;

Floating point type:

This is for real numbers used for calculation such as square roots, sine and cosine. These are of two types.

Float- Width in bits is 32 and range is from 1.4e-045 to 3.4e + 038. Float is used as a variable type for the fractional component, but specifies single precision. It can be used in representing dollars and cents.

Declaration:

Float hightemp;

Double- Width in bits is 64 and range is from 4.9e-324 to 1.8e + 308.it is used and is optimized in such a way that I can be used for high speed mathematic calculation. It has double precision which is faster than the single precision. Function such as sin()and sqrt() etc, return double values.

Declaration:

Double pi, r, a;
r = 10.4;
pi = 3.14;
a = pi* r * r;

Characters:

• The data type used store or declare character in java is char.
• It is 16-bit type in java. Range of a char is 0 to 65,536.
• There are no chars which are negative in nature.

Program demonstration for char
Class charExample
{
Public static void main (String args []) {
Char a, b;
a=88;
b=’y’;
system.out.print (“a and b: “);
system.out.println (a + “ “ +b);
}
}

Booleans:

• It is a primitive type for logical values.
• This tends have only one of two possible values, true or false.
• It is governed by if or for control state

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