props.put("key2", props.get("key2"));
        props.put("key3", "foo");
        props.save(System.err);
        System.err.println("=====");
    }

    @Test
    public void testJavaUtilPropertiesCompatibility() throws Exception {
        MavenProperties properties = new MavenProperties();
        properties.load(new StringReader(TEST_PROPERTIES));

        String test = properties.getProperty("test");