What is type conversion and casting?

[Jagriti]

Hi friends,

One of the most essential concept about programming and which is uncleared for me is "type conversion and casting". I am unable to understand this concept because of it's complexity. what is meant by type conversion and casting? What is the use of type conversion and casting? Please recommend me to understand the concept of type conversion and casting. Your help will be appreciated.

[Katty]

In the field of programming "Type conversion" and "casting" are use to convert an entity of one data-type into another datatype.

In OOPs(object-oriented programming), "Type conversion" allows programs to behave objects of one data-type as one of their types of ancestor to make simple interaction with them.

Every programming language has different rule of type conversion and casting.Mainly there are 2 types of conversion i.e explicit & implicit. The more common form of explicit conversion type is called as casting

[Zecho]

Hi friend,

The process of converting value of the one data-type into the another data-type is called as "casting" OR "Type conversion".

Basically there are 2 types of casting 1.Up-casting and 2.Down-casting:

1.Up-casting:It is the process of converting value of the lowar data-type into the data-type which is larger.

2.Down-casting:It is the process of converting value of the larger data-type into the data-type which is smaller.

[Reegan]

Below go through below program code ,which will definitely give you the basic idea behind the "Type conversion" OR "Casting":

Program code:

public class conversion{
public static void main(String[] args){
boolean t1 = true;
byte b1 = 2;
short s1 = 100;
char c1 = 'C';
int i1 = 200;
long l1 = 24000;
float f1 = 3.14f;
double d1 = 0.000000000000053;
String g1 = "string";
System.out.println("Value of all the variables like");
System.out.println("t1 = " + t1 );
System.out.println("b1 = " + b1 );
System.out.println("s1 = " + s1 );
System.out.println("c1 = " + c1 );
System.out.println("i1 = " + i1 );
System.out.println("l1 = " + l1 );
System.out.println("f1 = " + f1 );
System.out.println("d1 = " + d1 );
System.out.println("g1 = " + g1 );
System.out.println();
//Convert from boolean to byte.
b1 = (byte)(t1?1:0);
System.out.println("Value of b1 after conversion : " + b1);
//Convert from boolean to short.
s1 = (short)(t1?1:0);
System.out.println("Value of s after conversion : " + s1);
//Convert from boolean to int.
i1 = (int)(t1?1:0);
System.out.println("Value of i after conversion : " + i);
//Convert from boolean to char.
c = (char)(t?'1':'0');
System.out.println("Value of c1 after conversion : " + c1);
c = (char)(t?1:0);
System.out.println("Value of c1 after conversion in unicode : " + c1);
//Convert from boolean to long.
l1 = (long)(t1?1:0);
System.out.println("Value of 1l after conversion : " + l1);
//Convert from boolean to float.
f1 = (float)(t1?1:0);
System.out.println("Value of f1 after conversion : " + f1);
//Convert from boolean to double.
d1 = (double)(t1?1:0);
System.out.println("Value of d1 after conversion : " + d1);
//Convert from boolean to String.
g1 = String.valueOf(t);
System.out.println("Value of g1 after conversion : " + g1);
g1 = (String)(t1?"1":"0");
System.out.println("Value of g1 after conversion : " + g1);
int sum = (int)(b1 + i1 + l1 + d1 + f1);
System.out.println("Value of sum after conversion : " + sum);
}
}