http://www.java2s.com/Tutorials/Java/Algorithms/Shell_sort_implementation_in_Java.htm

public class Main {

  public static void main(String[] args) {

    int maxSize = 10;

    ShellSort arr = new ShellSort(maxSize);

/*w w  w . j a  va2  s. co  m*/

    for (int j = 0; j < maxSize; j++) {

      long n = (int) (java.lang.Math.random() * 99);

      arr.insert(n);

    }

    arr.display();

    arr.shellSort();

    arr.display();

  }

}

 

class ShellSort {

  private long[] data;

 

  private int len;

 

  public ShellSort(int max) {

    data = new long[max];

    len = 0;

  }

 

  public void insert(long value) {

    data[len] = value;

    len++;

  }

 

  public void display() {

    System.out.print("Data:");

    for (int j = 0; j < len; j++)

      System.out.print(data[j] + " ");

    System.out.println("");

  }

 

  public void shellSort() {

    int inner, outer;

    long temp;

    // find initial value of h

    int h = 1;

    while (h <= len / 3)

      h = h * 3 + 1; // (1, 4, 13, 40, 121, ...)

 

    while (h > 0) // decreasing h, until h=1

    {

      // h-sort the file

      for (outer = h; outer < len; outer++) {

        temp = data[outer];

        inner = outer;

        // one subpass (eg 0, 4, 8)

        while (inner > h - 1 && data[inner - h] >= temp) {

          data[inner] = data[inner - h];

          inner -= h;

        }

        data[inner] = temp;

      }

      h = (h - 1) / 3; // decrease h

    }

  }

 

}