...

...

        InputStream is = new ByteArrayInputStream(input.getBytes(StandardCharsets.UTF_8));

        InputStreamThread thread = new InputStreamThread(is, StandardCharsets.UTF_8, 5, null);
        thread.start();
        thread.join(1000);

        String output = thread.getOutput();
        assertTrue(output.contains("line1"));
        assertTrue(output.contains("line2"));
        assertTrue(output.contains("line3"));
    }

    @Test

                return StringUtils.join(newInputs, ",");
            }
            return StringUtils.join(newInputs, ",") + "=>" + StringUtils.join(newOutputs, ",");
        }
        if (Arrays.equals(inputs, outputs)) {
            return StringUtils.join(inputs, ",");
        }
        return StringUtils.join(inputs, ",") + "=>" + StringUtils.join(outputs, ",");
    }

        startLatch.countDown();

        // Wait for writer thread to complete
        writerThread.join(1000);

        // Wait for all reader threads to complete
        for (Thread thread : readerThreads) {
            thread.join(testDurationMs + 1000);
        }

        // Verify that alive was changed to false

    }

    /**
     * Joins array or list elements into a single space-separated string.
     *
     * @param input the input object (String[], List, or String)
     * @return joined string with elements separated by spaces, or empty string if invalid input
     */
    public static String join(final Object input) {
        String[] values = null;

        JobProcess jobProcess = new JobProcess(mockProcess, 100, callback);
        InputStreamThread thread = jobProcess.getInputStreamThread();

        thread.start();
        thread.join(1000);

        assertEquals(2, callbackResults.size());
        assertEquals("integration test", callbackResults.get(0));
        assertEquals("second line", callbackResults.get(1));

        if (r.exitCode != 0) {
            throw new AssertionError(String.join(" ", cmd) + " failed: " + r);
        }
    }

    private static String stdout(String... cmd) throws IOException, InterruptedException {
        ExecResult r = exec(cmd);
        if (r.exitCode != 0) {
            throw new AssertionError(String.join(" ", cmd) + " failed: " + r);
        }
        return r.stdout;
    }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join();
        }

        // Verify no exceptions occurred
        for (int i = 0; i < threadCount; i++) {
            assertNull(exceptions[i], "Thread " + i + " threw exception");

     *
     * @return compact string representation of the mapping rule
     */
    public String toLineString() {
        if (isUpdated()) {
            return StringUtils.join(newInputs, ",") + "=>" + newOutput;
        }
        return StringUtils.join(inputs, ",") + "=>" + output;
    }