### Question:
SystemBean implements CommandListener { @Command public String properties() { final PrintString out = new PrintString(); System.getProperties().list(out); return out.toString(); }  @Command String date(); @Command String env(); @Command String properties();  }### Answer:
@Test public void testProperties() throws Exception { final String properties = (String) main.exec("properties"); assertNotNull(properties); final Enumeration<?> property = System.getProperties().propertyNames(); while(property.hasMoreElements()) { assertTrue(properties.contains(property.nextElement() + "")); } }