/* This class gives abstract definition for a reference generater. 

*/

public abstract class ReferenceGenerator {

    int numPages;  /* Total number of pages in the process. */



    /* This constructor creates a reference generator with number of pages = numPages. 

     */

    public ReferenceGenerator (int numPages) {

	this.numPages = numPages;

    }



    /* This method generates the next page reference.

     */ 

    public abstract int nextReference ();



    /* This method initializes the random seed.

     */

    public abstract void init (long seed);

}