Java : class with another class

/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */

class nonStatic
{
public boolean isUnique(String str)
{
return false;
}
}

class Ideone
{

public static void main (String[] args) throws java.lang.Exception
{
String s = "hai hello hai dude!";
String[] arr = new String[20];
arr = s.split(" ");
System.out.println("Hai" + s);
for (String w : arr)
{
System.out.println("h" + w);
}

boolean t;
nonStatic n = new nonStatic();
t = n.isUnique("sdfsdfsdf");
System.out.println("hi" + t);
}



}