@Test
    public void testIsMultiValued() {
        Metadata meta = new Metadata();
        assertFalse(meta.isMultiValued("key"));
        meta.add("key", "value1");
        assertFalse(meta.isMultiValued("key"));
        meta.add("key", "value2");
        assertTrue(meta.isMultiValued("key"));
    }
Test for <code>isMultiValued()</code> method.
tika-core/src/test/java/org/apache/tika/metadata/TestMetadata.java