### Question:
CachedCommandModel extends CommandModelData { public String getETag() { if (eTag == null) { eTag = computeETag(this); } return eTag; } CachedCommandModel(String name);  CachedCommandModel(String name, String eTag); String getETag(); void setETag(String eTag); String geteTag(); void seteTag(String eTag); String getUsage(); void setUsage(String usage); boolean isAddedUploadOption(); void setAddedUploadOption(boolean addedUploadOption); static String computeETag(CommandModel cm);  }### Answer:
@Test public void testETag() { CachedCommandModel beatles1 = createBeateles(); assertNotNull(beatles1.getETag()); assertFalse(beatles1.getETag().isEmpty()); CachedCommandModel beatles2 = createBeateles(); assertEquals(beatles1.getETag(), beatles2.getETag()); CachedCommandModel beatles3 = createBeateles(); beatles3.add(new CommandModelData.ParamModelData("Sutcliffe", String.class, true, "R.I.P.", null, true, "Stuart")); assertFalse(beatles1.getETag().equals(beatles3.getETag())); CachedCommandModel beatles4 = createBeateles(); beatles4.dashOk = false; assertFalse(beatles1.getETag().equals(beatles4.getETag())); }