CaseInsensitiveConcurrentHashMap { public V get(final String key) { return this.map.get(key.toLowerCase()); }  V put(final String key, final V value); V get(final String key); boolean containsKey(final String key); V remove(final String key); List<String> getKeys();  }
@Test public void testGet() { this.map.put(LOWER_KEY, VALUE_1); this.map.put(UPPER_KEY, VALUE_2); assertThat(this.map.get(LOWER_KEY)).isEqualTo(VALUE_2); assertThat(this.map.get(UPPER_KEY)).isEqualTo(VALUE_2); assertThat(this.map.get(WRONG_KEY)).isNull(); }