protected void delete(String vplsName) {
        if (vplsName == null) {
            print(INSERT_VPLS_NAME);
            return;
        }
        VplsData vplsData = vpls.getVpls(vplsName);
        if (vplsData == null) {
            print(VPLS_NOT_FOUND, vplsName);
            return;
        }
        if (CHANGING_STATE.contains(vplsData.state())) {
            // when a VPLS is updating, we shouldn't try modify it.
            print("VPLS %s still updating, please wait it finished", vplsData.name());
            return;
        }
        vpls.removeVpls(vplsData);
    }
@Test
    public void testDelete() {
        ((TestVpls) vplsCommand.vpls).initSampleData();
        vplsCommand.command = VplsCommandEnum.DELETE.toString();
        vplsCommand.vplsName = VPLS1;
        vplsCommand.doExecute();
        Collection<VplsData> vplss = vplsCommand.vpls.getAllVpls();
        assertEquals(1, vplss.size());
    }