assertNotNull(result);
            assertNotNull(result.getContent());
            assertTrue(result.getContent().contains("テスト"));
        }
    }

    /**
     * Test that validateInputStream throws appropriate exception for null input.
     */
    public void test_validateInputStream_throwsExceptionForNull() {
        final TextExtractor extractor = container.getComponent("textExtractor");

    public int getWeight() {
        return 2; // Higher priority than TikaExtractor (weight=1)
    }

    @Override
    public ExtractData getText(final InputStream in, final Map<String, String> params) {
        validateInputStream(in);

        final Charset charset = getCharset(params);
        final List<String[]> rows = new ArrayList<>();
        String[] headers = null;