#vulnerable code 
                                @Test
    public void testClose() throws Exception {
        // use NullSender
        Properties props = System.getProperties();
        props.setProperty(Config.FLUENT_SENDER_CLASS, NullSender.class.getName());

        // create logger objects
        FluentLogger.getLogger("tag1");
        FluentLogger.getLogger("tag2");
        FluentLogger.getLogger("tag3");

        Map<String, FluentLogger> loggers;
        {
            loggers = FluentLogger.getLoggers();
            assertEquals(3, loggers.size());
        }

        // close and delete
        FluentLogger.close();
        {
            loggers = FluentLogger.getLoggers();
            assertEquals(0, loggers.size());
        }
    } 
                            #location 10 
                            #vulnerability type RESOURCE_LEAK
#fixed code
                                @Test
    public void testClose() throws Exception {
        // use NullSender
        Properties props = System.getProperties();
        props.setProperty(Config.FLUENT_SENDER_CLASS, NullSender.class.getName());

        // create logger objects
        FluentLogger.getLogger("tag1");
        FluentLogger.getLogger("tag2");
        FluentLogger.getLogger("tag3");

        Map<String, FluentLogger> loggers;
        {
            loggers = FluentLogger.getLoggers();
            assertEquals(3, loggers.size());
        }

        // close and delete
        FluentLogger.close();
        {
            loggers = FluentLogger.getLoggers();
            assertEquals(0, loggers.size());
        }

        props.remove(Config.FLUENT_SENDER_CLASS);
    }