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

/***************************************************************************

    <p><i>JSortItem</i>

    <p>This object is the Java equivalent to a pointer to a sort item in
    a memory page.

    <p><i>Development Environment</i>

    <p>Compiled under JDK 1.2.0, Jini 1.0.0 <p>

 ***************************************************************************/

    public class JSortItem
      {

/**   Real page number (0 based). *//*
      ================================  */

      int iRealPageNumber;


/**   Byte offset of the beginning of the item. *//*
      ==============================================  */

      int iItemOffset;



/*=========================================================================
              The following methods are in alphabetical order
  =========================================================================*/



/*    G E T   I T E M
 */
/**   This method assumes that the virtual page that contains the 
 *    requested item is already in memory.  This method then stores 
 *    the real page number and the byte offset of the item in this
 *    object's instance variables.
 *
 *    @param jobIn - the job that contains the real and virtual page arrays.
 *    @param lItemNumberIn - the requested sort item number.
 *
 */
public void getItem (JSortJob jobIn, long lItemNumberIn)
      {
      int iItemVPage;                  /* Virtual page num that holds item.  */


/*    Calculate the virtual page number for the requested item.
      =========================================================  */

      iItemVPage = (short) (lItemNumberIn / jobIn.items_pr_page);


/*    Pick the real page slot that holds the item's virtual page
      and store it in the instance variable.
      ===========================================================  */

      for 
        (
        iRealPageNumber = 0; 
        jobIn.vpage_num[iRealPageNumber] != iItemVPage; 
        iRealPageNumber++
        );


/*    Calculate the byte offset of the first byte in the item and
      store it in the instance variable.
      ===========================================================  */

      iItemOffset = (int) (lItemNumberIn % jobIn.items_pr_page) 
        * jobIn.itemlgth;

      }



/*    T O   S T R I N G
 */
/**
 */
public String toString ()
      {
      String s;

      s = "<pg" + iRealPageNumber + ":ofs" + iItemOffset + ">";
      return (s);
      }

      }


/*==========================(  End of Source  )============================*/