@Test
    public void test_getScriptEngine_errorMessagePreservesCase() {
        try {
            scriptEngineFactory.getScriptEngine("MyNonExistentEngine");
            fail("Should throw ScriptEngineException");
        } catch (ScriptEngineException e) {
            assertEquals("MyNonExistentEngine is not found.", e.getMessage());
        }
    }

    // Test engine replacement by class name
    @Test