SystemPropertiesConfiguration extends AbstractConfiguration implements Configuration { @Override public Object getValue(final String key) { assertFalse(key.contains(".")); return getProperty(key); }  @SuppressWarnings("unchecked") @Override Map<String, Object> asMap(); @Override void define(final String key, final Object value); @Override Configuration getSubconfiguration(final String key); @Override Object getValue(final String key); @Override void remove(final String key);  }
@Test public void testGetValue() { final SystemPropertiesConfiguration configuration = new SystemPropertiesConfiguration(); final Object value = configuration.getValue(randomUUID().toString()); assertNull(value); }