@Test
    public void testToStringWithSingleEntry() {
        Metadata m = new Metadata();
        m.add("key", "value1");
        assertEquals("key=value1", m.toString());
    }
Defines a composite property, then checks that when set as the
composite the value can be retrieved with the property or the aliases
tika-core/src/test/java/org/apache/tika/metadata/TestMetadata.java