@Test
public void testGetSymbols() {


    //create two stock symbols
    String symbol = "testsymbol";

    Map<String,String> obj = persistence.createSymbol(symbol);
    persistence.saveSymbol(symbol);

    String symbol2 = "testsymbol2";
    Map<String,String> obj2 = persistence.createSymbol(symbol2);
    persistence.saveSymbol(symbol2);


    Set<String> symbols = persistence.getSymbols();

    //Ensure that both stock symbols exist and can be queried.
    assertTrue(symbols.contains(symbol));
    assertTrue(symbols.contains(symbol2));
}