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Java Wrapper Class: Integer

Java Wrapper Class: Integer

Get a brief introduction to Integer, a Java wrapper class.

We'll cover the following...

Introducing Integer

The Integer class is part of the java.lang package.

The Integer class is a wrapper class for the primitive type int. It contains several methods to effectively deal with an integer. An object of an Integer class can hold a single int value.

Note: To get an overview of what a wrapper class is, check out this shot.

Creating an Integer object

This class has two constructors:

  • Integer (int value)
  • Integer (String string)

Let’s cover them one by one.

The Integer (int value) constructor

This constructor constructs a new Integer object that represents the specified int value.

Look at the program below.

Java
class IntegerWrapperDemo1 
{
    public static void main( String args[] ) 
    {
        Integer x = new Integer(5); // Creating an Integer type object
        System.out.println( x );
    }
}

Look at line 5. We create the Integer object: x. We pass 55 as the argument. Now when we try to print x, we get 55 ...