docMap.put("mimetype", mimeType);
            assertFalse("Should not support " + mimeType, thumbnailGenerator.isTarget(docMap));
        }
    }

    @Test
    public void test_concurrentOperations() throws InterruptedException {
        // Test thread safety with concurrent operations
        final int threadCount = 10;
        Thread[] threads = new Thread[threadCount];

        } finally {
            if (outputFile.exists()) {
                outputFile.delete();
            }
        }
    }

    // Test concurrent access patterns
    @Test
    public void test_concurrent_operations() throws Exception {
        final CommandGenerator generator1 = new CommandGenerator();
        final CommandGenerator generator2 = new CommandGenerator();