The general form to create a sub-package is

Where package2 is inside package1.
To use the classes and interfaces of package2 we can write the import statement as
import package1.package2;
Let us see a program that we are creating a package technology inside the package silan by writing the statement

And in this sub-package we are declaring a class simple with a method display ( ).

Output

Examples for practice

1. The class given below have saved in the folder "Silan". Will the program execute?

Example:

package Silan;
class Technology
{
	public void show( )
	{
	}
	public void get( )
	{
	}
	public static void main(String args[ ])
	{
		System.out.println("package is created");
	}
}

2. The code uses the class defined above. Class SilanSoftware is not defined in technology folder. Will the code execute without giving any errors ?

Example:

import technology.Vivtech ;
class SilanSoftware
{
	public static void main( String args[ ] )
	{
		technology.Vivtech v=new technology.Vivtech( );
		System.out.println("art of java programming");
	}
}

3. The method show( ) in Vivtech has been set as private. Class Silan is in the same package as Vivtech. Will the class able to use the method ?

Example:

package technology ;
import technology.Vivtech ;
class Silan
{
	public static void main(String args[ ])
	{
		Vivtech v=new Vivtech( ) ;
		v.show( ) ;
	}
}

4. Importing a complete package with all its classes has been demonstrated in the program. Will the class compile ?

w3-example

import technology ;
class Silan
{
	public static void main(String args[ ])
	{
		technology.Vivtech v=new technology.Vivtech( );
		System.out.println("programming in java");
	}
}

5. What will be the output ?

Example

package main;
class Base
{
	public void Print()
	{
		System.out.println("Base");
	}     
}
class Derived extends Base
{
	public void Print()
	{
		System.out.println("Derived");
	}
}
class Main
{
	public static void DoPrint( Base o )
	{
		o.Print();   
	}
	public static void main(String[] args)
	{
		Base x = new Base();
		Base y = new Derived();
		Derived z = new Derived();
		DoPrint(x);
		DoPrint(y);
		DoPrint(z);
	}
}