Java Source

Dear all
I made a java class that copies the data from a table and write it to a file named "c:\tarek.txt"
the class works fine and the file is created successfuly.

I descided to make a java source that include this class.
but i execute function that call the java source , the file is not created.
the following is my code
----------------
-- java source
CREATE OR REPLACE AND RESOLVE JAVA SOURCE NAMED "CreateFile" AS
import java.io.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class CreateFile{

public static String getData(){
String file_name = "c:\\tarek.txt";
try{
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
Connection con = DriverManager.getConnection("jdbc:oracle:thin:@192.168.85.10:1521:orahr","sal","sal1");
Statement stm = con.createStatement();
ResultSet rs = stm.executeQuery("select region_code,region_name from nmp_region");

BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
File file = new File(file_name);
FileWriter fstream = new FileWriter(file_name);
BufferedWriter out = new BufferedWriter(fstream);
while(rs.next())
{
int col = rs.getInt(1);
String val = rs.getString(2);
out.write(val);
}

rs.close();
con.close();
out.close();

}

catch(Exception e){
System.out.println(e);
}
return("File created successfully.");
}
public static void main(String args[])
{
CreateFile c = new CreateFile();
c.getData();
}
};
/
----------------------------------
--- function
CREATE OR REPLACE FUNCTION copytofile
RETURN varchar2
AS LANGUAGE JAVA
NAME 'CreateFile.getData () return java.lang.String';
/

------- test
SQL> select copytofile from dual;

COPYTOFILE
--------------------------------------------------------------------------------
File created successfully.

the problem is that the file is not created
I do not know why
please help