Page 145 - ComputerScience_Class_11

5 short sd;
6 int id;
7 long ld = 2571;

8 double dd = 323.14;
9 System.out.print("Converting long to int: ");
10 id = (int)ld;

11 System.out.println("long ld = " +ld+ " int id = " +id);
12 System.out.println("---------------------------------------------");
13 System.out.print("Converting double to short: ");

14 sd = (short)dd;
15 System.out.println("double dd = " +dd+ " short sd = " +sd);
16 }

17 }

The output of the preceding program is as follows:
BlueJ: Terminal Window - Java

Options

Converting long to int: long ld = 2571 int id = 2571
---------------------------------------------
Converting double to short: double dd = 323.14 short sd = 323

Note: The boolean data type is not compatible with any other primitive data types. So, it cannot be
converted to any other type or vice versa neither by implicit nor explicit data type conversion.

6.6 WRAPPER CLASS
Wrapper classes are in-built classes that contain primitive data types. These classes are used to convert primitive data
types into objects and vice-versa with the help of their methods. Every wrapper class has various methods. Thus, it
provides a way to use the primitive data types (short, double, boolean, etc.) as objects. Every primitive data type is
attached to its wrapper class. For example, the float data type is attached to the Float class, the double data type
is attached to the Double class and so on.

6.6.1 Corresponding Wrapper Classes for Each Primitive Type
The wrapper class is used to convert the primitive data type to its object and vice versa. A wrapper class is required to:
• Store the primitive data type in an object.
• Convert String to primitive data type and vice versa.
Each primitive data type has its own wrapper class. Some of the wrapper class lists are as follows.
Primitive Data Type Wrapper Class

byte Byte
short Short
int Integer

Primitive Values, Wrapper Classes, Types and Casting 143