CharMappingItem item = new CharMappingItem(1L, inputs, "output");

        assertEquals("a,b,c=>output", item.toLineString());
    }

    public void test_toLineString_withUpdates() {
        String[] inputs = { "old1", "old2" };
        CharMappingItem item = new CharMappingItem(1L, inputs, "oldOutput");

        item.setNewInputs(new String[] { "new1", "new2", "new3" });
        item.setNewOutput("newOutput");

        String content = "new1\n" + "new2\n" + "new3\n";

        InputStream is = new ByteArrayInputStream(content.getBytes(StandardCharsets.UTF_8));
        stopwordsFile.update(is);

        assertEquals(3, stopwordsFile.stopwordsItemList.size());
        assertEquals("new1", stopwordsFile.stopwordsItemList.get(0).getInput());
        assertEquals("new2", stopwordsFile.stopwordsItemList.get(1).getInput());

                v3(),
                (oldV, newV) -> {
                  assertEquals(v0(), oldV);
                  assertEquals(v3(), newV);
                  return null;
                }));
    expectMissing(e0());
  }

  public void testMergeNullValue() {
    try {
      getMap()
          .merge(
              k0(),
              null,
              (oldV, newV) -> {

                v3(),
                (oldV, newV) -> {
                  assertEquals(v0(), oldV);
                  assertEquals(v3(), newV);
                  return null;
                }));
    expectMissing(e0());
  }

  public void testMergeNullValue() {
    try {
      getMap()
          .merge(
              k0(),
              null,
              (oldV, newV) -> {

   * @param newN the expected number of entries once duplicates are removed
   * @param duplicates a map of canonical {@link Entry} objects for each duplicate key. This map
   *     will be updated by the method, setting each value to false as soon as the {@link Entry} has
   *     been included in the new entry array.
   * @return an array of {@code newN} entries where no key appears more than once.
   */

        try {
            // Create a new QueryProcessor and initialize it
            QueryProcessor newQueryProcessor = new QueryProcessor();
            newQueryProcessor.init();
            ComponentUtil.register(newQueryProcessor, "queryProcessor");

            // Register the command with the new processor
            PrefixQueryCommand newCommand = new PrefixQueryCommand();
            newCommand.register();

        assertArrays(new String[] { "ja" }, fessConfig.normalizeQueryLanguages(new String[] { "ja" }));
        assertArrays(new String[] { "ja" }, fessConfig.normalizeQueryLanguages(new String[] { "ja", "ja" }));
        assertArrays(new String[] { "ja" }, fessConfig.normalizeQueryLanguages(new String[] { "ja-jp" }));
        assertArrays(new String[] { "ja" }, fessConfig.normalizeQueryLanguages(new String[] { "ja_JP" }));

        // Test deeply nested exception causes
        Exception level3 = new Exception("Level 3: Database connection failed");
        Exception level2 = new Exception("Level 2: User lookup failed", level3);
        Exception level1 = new Exception("Level 1: Authentication service error", level2);
        SsoProcessException topLevel = new SsoProcessException("SSO process failed", level1);

        // Verify the chain

        final Exception[] exceptions = new Exception[threadCount];

        for (int i = 0; i < threadCount; i++) {
            final int index = i;
            threads[i] = new Thread(() -> {
                try {
                    providers[index] = new FessTimeResourceProvider(mockConfig);
                } catch (Exception e) {
                    exceptions[index] = e;
                }

        final NullPointerException npeCause = new NullPointerException("Null query parameter");
        final IllegalStateException iseCause = new IllegalStateException("Invalid parser state");
        final OutOfMemoryError oomCause = new OutOfMemoryError("Query too large");

        // Execute
        final InvalidQueryException npeException = new InvalidQueryException(messageCode, message, npeCause);