@Test
    public void testRemove() {
        Metadata meta = new Metadata();
        meta.remove("name-one");
        assertEquals(0, meta.size());
        meta.add("name-one", "value-1.1");
        meta.add("name-one", "value-1.2");
        meta.add("name-two", "value-2.2");
        assertEquals(2, meta.size());
        assertNotNull(meta.get("name-one"));
        assertNotNull(meta.get("name-two"));
        meta.remove("name-one");
        assertEquals(1, meta.size());
        assertNull(meta.get("name-one"));
        assertNotNull(meta.get("name-two"));
        meta.remove("name-two");
        assertEquals(0, meta.size());
        assertNull(meta.get("name-one"));
        assertNull(meta.get("name-two"));
    }
Test for <code>remove(String)</code> method.
tika-core/src/test/java/org/apache/tika/metadata/TestMetadata.java