assertThat(node, allOf(
                hasProperty(propertyName(containsString("y"))),
                hasProperty("abc", containsString("oo")),
                hasProperty(
                        Matchers.<Property>allOf(
                                propertyName(containsString("ef")),
                                propertyValue(isA(Long.class))
                        )
                )
        ));

        // It's a pity we have to help the either().or() matcher with generics here, but I couldn't find a way around that. Other option is to use anyOf() which I find less readable.
        assertThat(node, everyProperty(Matchers.<Property>either(propertyName(startsWith("jcr:"))).or(propertyValue(equalTo("mgnl:dummyNode")))));