assertEquals("c", item1.getOutput());

        OptionalEntity<CharMappingItem> result2 = charMappingFile.get(2L);
        assertTrue(result2.isPresent());
        CharMappingItem item2 = result2.get();
        assertEquals(2L, item2.getId());
        assertArrayEquals(new String[] { "d", "e" }, item2.getInputs());
        assertEquals("f", item2.getOutput());

        charMappingService.getCharMappingItem(form.dictId, form.id).ifPresent(entity -> {
            form.inputs = entity.getInputsValue();
            form.output = entity.getOutput();
        }).orElse(() -> {
            throwValidationError(messages -> messages.addErrorsCrudCouldNotFindCrudTable(GLOBAL, form.getDisplayId()),
                    () -> asListHtml(form.dictId));
        });

        assertEquals("line1 line2", item.getOutput());
    }

    public void test_constructor_withNullOutput() {
        // Test with null output
        String[] inputs = { "input" };
        CharMappingItem item = new CharMappingItem(1L, inputs, null);

        assertNull(item.getOutput());
    }

    public void test_constructor_withUnsortedInputs() {

    }

    @ParametricNullness
    abstract T getOutput(int entry);

    @Override
    @ParametricNullness
    public T next() {
      checkForConcurrentModification();
      if (!hasNext()) {
        throw new NoSuchElementException();
      }
      indexToRemove = currentIndex;
      T result = getOutput(currentIndex);
      currentIndex = getSuccessor(currentIndex);

        stemmerOverrideService.getStemmerOverrideItem(form.dictId, form.id).ifPresent(entity -> {
            form.input = entity.getInput();
            form.output = entity.getOutput();
        }).orElse(() -> {
            throwValidationError(messages -> messages.addErrorsCrudCouldNotFindCrudTable(GLOBAL, form.getDisplayId()),
                    () -> asListHtml(form.dictId));
        });

            this.output = output;
        }

        @Override
        public void start() {
        }

        @Override
        public String getOutput() {
            return output;
        }
    }

    private static class TestSystemHelper extends SystemHelper {
        File tempFile;

        @Override

        final EditBody body = new EditBody();
        body.id = entity.getId();
        body.dictId = dictId;
        body.input = entity.getInput();
        body.output = entity.getOutput();
        return body;
    }

        final EditBody body = new EditBody();
        body.id = entity.getId();
        body.dictId = dictId;
        body.inputs = entity.getInputsValue();
        body.output = entity.getOutput();
        return body;
    }

        }

        @Override
        public void run() {
            // Override run to do nothing in test
        }

        @Override
        public String getOutput() {
            return output;
        }
    }

    private static class TestServletContext implements ServletContext {
        File parentFile = new File("/test/webapp");

        @Override

        // Custom join method to avoid overriding final Thread.join()
        public void waitForCompletion(long millis) {
            // Mock implementation
        }

        @Override
        public String getOutput() {
            return output;
        }
    }

    // Mock Process implementation
    private class MockProcess extends Process {
        private final int exitValue;