}

    @Test
    public void test_instanceof_FessSystemException() {
        // Test that DictionaryException is instance of FessSystemException
        DictionaryException exception = new DictionaryException("Test");

        assertTrue(exception instanceof org.codelibs.fess.exception.FessSystemException);
        assertTrue(exception instanceof RuntimeException);

            assertEquals("testWord", result.getInput());
        } catch (Exception e) {
            // If any exception occurs, it should be a DictionaryException
            assertTrue("Exception should be DictionaryException", e instanceof DictionaryException);
            assertTrue("Message should mention userDict file",
                    e.getMessage().contains("userDict") || e.getMessage().contains("Failed to write"));

                throw new IOException("Test exception");
            }
        };

        try {
            stopwordsFile.reload(null, failingStream);
            fail("Should throw DictionaryException");
        } catch (DictionaryException e) {
            assertTrue(e.getMessage().contains("Failed to parse"));
        }
    }

    // Test update with InputStream
    @Test

        charMappingFile.update(updateItem1);

        // Second update should fail due to mismatch
        try {
            charMappingFile.update(updateItem2);
            fail("Should throw DictionaryException");
        } catch (DictionaryException e) {
            assertTrue(e.getMessage().contains("Mapping file was updated"));
        }
    }

    // Test reload with IOException
    @Test