A randomized divide-and-conquer algorithm

There is nothing new here. My Java code to find the smallest element in an array(Algorithms book by S. Dasgupta, C. H. Papadimitriou, and U. V. Vazirani). The code is written based on the pseudo-code.

I am using Google guava here.

Ints.toArray( less )

This is the algorithm definition.

import com.google.common.primitives.Ints;

import java.util.ArrayList;
import java.util.Random;

import static java.util.Arrays.sort;

public class KThLargestSelection {

    private Random r = new Random();

    static int[] a1 = new int[]{ 0,2,7,3,4,9};

        public int findKThLargest(  int[] a, int k ){

                int pivot = getPivot(a);

                ArrayList<Integer> less = new ArrayList<>();
                ArrayList<Integer> equal = new ArrayList<>();
                ArrayList<Integer> great = new ArrayList<>();

                for( int value : a ){
                        if ( value < pivot){
                            less.add( value );
                        } else if ( value == pivot){
                            equal.add( value );
                        }else if ( value > pivot){
                            great.add( value );
                        }
                }
                        if (k <= less.size()) {
                            return findKThLargest (Ints.toArray( less ), k);
                        }else if (k <= less.size() + equal.size()){
                            return  pivot;
                        }else
                            return   findKThLargest (Ints.toArray( great  ), k - less.size() - equal.size());

        }

    private int getPivot( int[] data ){
        int[] highLow = new int[0];

            System.out.println("getPivot [" + data.length + "] " + toStringArray(data));
            highLow = new int[] { data[0],data[data.length - 1] };

        if( data.length >= 3){
            sort(new int[]{data[r.nextInt(2)],
                           data[r.nextInt(2)],
                           data[r.nextInt(2)]});
        }
        return highLow[ 1 ];
    }

    private String toStringArray(int[] data){
        StringBuilder sb = new StringBuilder();
        for( int i = 0 ; i < data.length ; i ++ ){
            sb.append( data[i] + " ");
        }
        return sb.toString();
    }
    
    public static void main( String... s){
        KThLargestSelection l = new KThLargestSelection();
        System.out.println( l.findKThLargest(a1, 1));
    }
}