@Test
public void testWriteXML() {
    
    String xmlfile = "src\\testfiles\\testWrite.xml";
    
    //create a valid stock symbol and insert test data. 
    String symbol = "testsymbol";
    Map<String,String> obj = persistence.createSymbol(symbol);
    obj.put("somefield", "somedata");
    persistence.saveSymbol(symbol);
    
    persistence.writeDB(xmlfile);
    
    File readfile = new File(xmlfile);
    assertNotNull(readfile);
    
    
}