### Question:
FilterValueHolderImpl implements FilterValueHolder { @Override public void put(String key, Integer value) { try { filterValue.put(key, value.toString()); empty = false; } catch (JSONException e) { throw new IllegalStateException(e.getMessage()); } } FilterValueHolderImpl();  FilterValueHolderImpl(FilterValueHolder holder); @Override JSONObject toJSON(); @Override void put(String key, Integer value); @Override void put(String key, BigDecimal value); @Override void put(String key, Long value); @Override void put(String key, String value); @Override void put(String key, boolean value); @Override boolean getBoolean(String key); @Override Integer getInteger(String key); @Override BigDecimal getBigDecimal(String key); @Override Long getLong(String key); @Override String getString(String key); @Override boolean has(String key); @Override Object remove(String key); @Override void put(String key, List<Long> value); @Override List<Long> getListOfLongs(String key); @Override void initialize(final JSONObject jsonObject); boolean isEmpty();  }### Answer:
@Test public final void shouldClearContentsWithoutException() { filterValueHolder.put("someBoolean", true); filterValueHolder.put("someDecimal", BigDecimal.ONE); filterValueHolder.put("someString", "stringValue"); try { ReflectionTestUtils.invokeMethod(filterValueHolder, "clearHolder"); } catch (ConcurrentModificationException cme) { Assert.fail(); } }