### Question:
JodaTimezoneCache { public static DateTimeZone getInstance(ByteBuffer timezoneId) { try { return cachedJodaTimeZones.get(timezoneId); } catch (ExecutionException ex) { throw new IllegalDataException(ex); } catch (UncheckedExecutionException e) { throw new IllegalDataException("Unknown timezone " + Bytes.toString(timezoneId.array())); } }  static DateTimeZone getInstance(ByteBuffer timezoneId); static DateTimeZone getInstance(ImmutableBytesWritable timezoneId); static DateTimeZone getInstance(String timezoneId); static final int CACHE_EXPRIRE_TIME_MINUTES; }### Answer:
@Test public void testGetInstanceByteBufferUTC() { DateTimeZone instance = JodaTimezoneCache.getInstance(ByteBuffer.wrap(Bytes.toBytes("UTC"))); assertNotNull(instance); }
@Test public void testGetInstanceString() { DateTimeZone instance = JodaTimezoneCache.getInstance("America/St_Vincent"); assertNotNull(instance); }
@Test(expected = IllegalDataException.class) public void testGetInstanceStringUnknown() { JodaTimezoneCache.getInstance("SOME_UNKNOWN_TIMEZONE"); }
@Test public void testGetInstanceImmutableBytesWritable() { ImmutableBytesWritable ptr = new ImmutableBytesWritable(Bytes.toBytes("Europe/Isle_of_Man")); DateTimeZone instance = JodaTimezoneCache.getInstance(ptr); assertNotNull(instance); }