create or replace and compile java source named "xxxxUtil"
    as
     import java.io.*;
     import java.lang.*;


   public class xxxxUtil extends Object
   {
          public static String RunThisS(String args)
          {
                    Runtime rt = Runtime.getRuntime();

                 String rcS = "";
                 int rc = -1;

                 try                     
                 {
                  Process p = rt.exec(args);
                  int bufSize = 8192;

                  BufferedInputStream bis = 
                         new BufferedInputStream(p.getInputStream(), bufSize);
                  int len;

                  byte buffer[] = new byte[bufSize];

                  // Echo back what the program spit out

                  while ((len = bis.read(buffer, 0, bufSize)) != -1)
                          System.out.write(buffer, 0, len);

                  rc = p.waitFor();
                 }
                 catch (Exception e)
                 {
                  e.printStackTrace();
                  rcS = e.getMessage();
                 }
                 finally
                 {
                  return rcS + rc ;
                 }
            }
            
    }
/


create or replace package xxxx_BACKUP
is
-- Author  : xxx
-- Purpose : Procedimientos para realizar el Backup de 
--           los objetos de base de datos
-- Ejecuta un comando del sistema

  FUNCTION RUN_CMD(p_cmd  in varchar2) return VARCHAR2;
  -------- EXPORT ESQUEMA --------
  
  PROCEDURE backup_esquema(ruta_exp  IN VARCHAR2,usuario  IN VARCHAR2,
                     contrasenia  IN VARCHAR2,nombre_fichero_dmp  IN VARCHAR2,
                     nombre_fichero_log  IN VARCHAR2,nombre_esquema  IN VARCHAR2,
                     resultado  OUT VARCHAR2);
end xxxx_BACKUP;
/

create or replace package body xxxx_BACKUP is

  -- Author  : xxx
  -- Purpose : Procedimientos para realizar el Backup 
  --           de los objetos de base de datos
  
  -- Ejecuta un comando del sistema
  FUNCTION RUN_CMD(p_cmd in varchar2) return VARCHAR2
  AS
    language java name 'xxxxUtil.RunThisS(java.lang.String) return VARCHAR2';

 
  
  -------- EXPORT ESQUEMA --------
  PROCEDURE backup_esquema (ruta_exp IN VARCHAR2, usuario IN VARCHAR2,
                      contrasenia IN VARCHAR2, nombre_fichero_dmp IN VARCHAR2, 
                      nombre_fichero_log IN VARCHAR2, 
                      nombre_esquema IN VARCHAR2, resultado OUT VARCHAR2) IS 
  BEGIN -- definicion del procedimiento
    resultado := RUN_CMD(ruta_exp || 'exp ' || un || '/' || pw 
                       || ' file=' || nombre_fichero_dmp || ' consistent=Y 
                       log=' || nombre_fichero_log || ' owner=' 
                       || some_owner );
  END;

end xxxx_BACKUP;
/

public List<Object> ejecutarUpdate(String sql, 
                                     List<Object> parametersIn, 
                                     List<Integer> parametersOut)
                                      throws SQLException {
    List<Object> retorno = new ArrayList<Object>();
    try {
      logger.debug("ejecutarSQL - SQL: " + sql);
      CallableStatement stmt = connection.prepareCall(sql);
      int in = 1;
      if (parametersIn != null) {
	Iterator<Object> itIn = parametersIn.iterator();
	while (itIn.hasNext()) {
	    stmt.setObject(in, itIn.next());
	    in++;
	}
      }

      int out = in;
      if (parametersOut != null) {
	Iterator<Integer> itOut = parametersOut.iterator();
	while (itOut.hasNext()) {
	    Integer current = itOut.next();
	    stmt.registerOutParameter(out, current.intValue());
	    out++;
	}
      }

      stmt.executeUpdate();
      connection.commit();
      for (; in < out; in++) {
	 retorno.add(stmt.getString(in));
     }
    
      if(logger.isDebugEnabled())
      {
    	 logger.debug("La sentencia ejecutada: "+sql);
    	 logger.debug("La sentencia ejecutada2: "+stmt);
      }
    
   } catch (SQLException e) {
      logger.error("ejecutarSQL() - excepcion: " + e.getMessage(), e);
      throw e;
   }
   return retorno;
}

SET FEEDBACK ON
SET SERVEROUTPUT ON SIZE 300000

declare
  cad  varchar2(1000);
begin
  cad := xxxx_backup.RUN_CMD('/bin/who i am');
  
  DBMS_OUTPUT.PUT_LINE('returns '
                       ||cad);
end;
/