create or replace and compile java source named directorylist as
package yourorganisation.directorylist;

import java.io.*;
import java.net.*;
import java.util.ArrayList;
import java.util.Arrays;

public class DirectoryList {

    static ArrayList globalFileList;
    /**********************************************************************/
    /*
    Get the listing as a string array, and stores in globalFileList
    */
    public static void getListing (String directory) {
      File path = new File( directory );
      String[] list = path.list();
      /* Convert array to ArrayList (to allow removal of element 0)*/
      globalFileList = new ArrayList (Arrays.asList (list));
    }
    /**********************************************************************/
    /*
    Gets the next name from the list.
    return "" if end of list.
    */
    public static String nextFileName() {
      String fileName="";
      
      if (globalFileList.size()>0) {
        fileName=(String)globalFileList.remove(0);
      }
      
      return(fileName);
    }
}

  --****************************************************************************
  PROCEDURE     Java_Directory_List_Get
    ( p_Directory_Name          IN      VARCHAR2
    )                           
  AS LANGUAGE JAVA
  NAME 'yourorganisation.directorylist.DirectoryList.getListing(java.lang.String)'
  ;
  --****************************************************************************
  FUNCTION      Java_Directory_List_Next_File
                                RETURN  VARCHAR2
  AS LANGUAGE JAVA
  NAME 'yourorganisation.directorylist.DirectoryList.nextFileName() return java.lang.String'
  ;
  --****************************************************************************  

  1  select *
  2  from table(util.ls('YOUR_DIR_NAME'))
  3  where name like '%.zip'
  4  and modified >= sysdate - 3
  5* and file_size > 1000000