public void deletePolicy(String policyName) {
        policies.remove(policyName);
    }
@Test
    public void testDeletePolicy() throws Exception {
        NamespaceIsolationPolicies policies = this.getDefaultTestPolicies();
        policies.deletePolicy("non-existing-policy");
        assertFalse(policies.getPolicies().isEmpty());

        policies.deletePolicy("policy1");
        assertTrue(policies.getPolicies().isEmpty());
    }